Bromodeoxyuridine Labeling Index as an Indicator of Early Tumor Response to Preoperative Radiotherapy in Patients with Rectal Cancer Purpose Assessment of tumor proliferation rate using Bromodeoxyuridine labeling index -LRB- BrdUrdLI -RRB- as a possible predictor of rectal cancer response to preoperative radiotherapy -LRB- RT -RRB- . Introduction In specialized centers , a refined surgical technique has resulted in high local control figures in rectal cancer . However , local recurrence rates after `` standard '' surgery are generally high , with figures ranging between 20 and 40 % 1,2 , although after adopting the total mesorectal excision -LRB- TME -RRB- concept they fell down to 10 -- 12 % 3,4 . Radiotherapy in addition to surgery significantly diminishes the risk of local failure by more than half , from 8 to 2 % after 2 years3 . Therefore , combined treatment : radiotherapy -LRB- RT -RRB- and surgery in the treatment of patients with resectable rectal cancer has been proposed in many trials using either preoperative5 ,6 or postoperative irradiation7 ,8 . Better results of preoperative RT for 5 days -LRB- 25 Gy in five fractions -RRB- in comparison with postoperative 60 Gy in 30 fractions were achieved by a Swedish group4 ,9,10 , with respect to the local recurrence rate11 and overall survival11 ,12 . A corresponding improvement in overall survival has not been demonstrated after postoperative radiotherapy alone13 . Graf 's 12 study provided a clinically significant biologic effect of a short preoperative course of radiotherapy on the tumor size and on the incidence of nodal metastases ; however , this effect was minimized if surgery was performed immediately after radiotherapy . The effect is most likely caused by death of tumor cells in the primary tumor and in the involved nodes . A short treatment course of radiotherapy , i.e. , 5 × 5 Gy is desirable , and this regimen is currently considered as the gold standard in many centers . However , using this schedule it is difficult to observe a down-staging and/or downsizing of the tumor , which is of importance for the selection of patients for sphincter-preserving surgery -LRB- anterior resection -RRB- . In clinical practice there are no certain methods able to predict tumor response to preoperative radiotherapy -LRB- RT -RRB- . The optimal timing of surgery after preoperative radiotherapy in rectal cancer is unknown . However , it was shown that a long interval -LRB- 6 -- 8 weeks -RRB- between preoperative radiotherapy -LRB- 39 Gy in 13 fractions -RRB- and surgery was associated with a significantly greater clinical tumor volume reduction than a short interval -LRB- 2 weeks -RRB- 14 . On the other hand , it was shown that subclinical pelvic deposits of rectal cancer could grow rapidly during preoperative radiation therapy and during the radiotherapy -- surgery interval , with an adverse influence on the rate of pelvic tumor control from protracting the overall treatment time15 . Graf et al12 showed that low doses in short RT only offer clinically relevant reduction in the risk of pelvic relapses if the overall radiation treatment time is short . Thus , the rate of cancer cell proliferation seems to be a very important prognostic factor . The aim of this study is to evaluate BrdUrd LI and S-phase fraction -LRB- SPF -RRB- as the possible indicators of tumor proliferation rate and predictors of the tumor response to neoadjuvant RT in patients with rectal cancer , and to suggest an optimal interval between short RT course and surgery . Methods and Materials Patients Between November 2003 and January 2006 we recruited 92 patients with resectable rectal carcinoma for whom curative surgery was planned . Patients were eligible for the trial if they were less than 75 years old , had a histopathologically proved adenocarcinoma -LRB- T2/T3 -RRB- 16 situated less than 12 cm from the verge of the anus , and gave informed consent for their participation . The protocol was approved by the Ethical Committee of the Center of Oncology , and each patient gave written consent . The criteria for exclusion were : locally nonresectable tumor ; plan to perform only local tumor excision ; known metastatic disease ; previous radiotherapy of pelvis region ; other malignant disease ; and patient 's refusal . Preoperative Radiotherapy The patients assigned to preoperative radiotherapy received a total tumor dose of 25 Gy . The treatment was given in five fractions over 5 days , one posterior and two lateral wedged fields were irradiated with photons of maximum 6 MV energy . According to the random selection surgery was performed the following week -LRB- schedule I -RRB- or after longer interval of 4 -- 5 weeks -LRB- schedule II -RRB- . Surgery Anterior resection of rectum or abdominoperineal excision was performed within a week or a month after the completion of RT. . Type of surgery was resection of the rectum and lower sigmoid with involved adjacent tissue and regional lymph nodes up to or above the origin of inferior mesenteric artery . A minimal touch technique was used with high tight ligation of the inferior mesenteric artery . The decision whether the patient should have an abdominoperineal resection or a sphincter-preserving surgery was made by the surgeon during the operation . An abdominoperineal resection of rectum was performed in 41 -LRB- 44.6 % -RRB- of the patients , and sphincter preserving surgery was performed in 51 -LRB- 55.4 % -RRB- . Biological Assessment of Tumor Response Tumor samples were taken twice : before radiotherapy -LRB- through a rectoscope -RRB- and during surgery from the same place , i.e. , at the lowest edge of the tumor mass . Each biopsy was divided into two parts : one was used for BrdUrd LI assessment , and the second was used for immunohistochemical analysis -LRB- these results will be the subject of a separate study -RRB- . Bromodeoxyuridine Labeling Index Incorporation of BrdUrd in tumor samples from a biopsy -LRB- 0.3 -- 0.5 cm3 -RRB- was carried out in vitro according to the high-pressure oxygen method . The BrdUrd staining procedure and flow cytometry have been described in detail elsewhere17 . The stained preparations were analyzed with a FACS Calibur flow cytometer -LRB- Becton Dickinson Immunocytometry Systems , Sunnyvale , CA , USA -RRB- by one coauthor -LRB- AG -RRB- and 20 × 103 events were collected in each histogram . The BrdUrdLI was calculated as a percentage of BrdUrd-labeled cells in a sample , which incorporated BrdUrd during 1 h of incubation at 37 °C -LRB- with discrimination of diploid subpopulation in aneuploid tumors -RRB- . The tumor ploidy and SPF were calculated from the DNA profile with ModFit software running on a MacIntosh computer . Apoptotic cells were identified as objects with a fractional DNA content not less than 20 % of the 2n DNA content . Cell death was calculated as the sum of apoptosis and debris . The tumor ploidy was estimated by evaluating the DNA index , i.e. , the ratio of the modal DNA fluorescence of abnormal to normal G1/0 cells . Aneuploidy was assessed in cases in which the normal and neoplastic cell populations gave two separate peaks . Human lymphocytes were used for the reference peak . Tumors with BrdUrdLI > 8.5 % -LRB- median value -RRB- were considered as fast , and those with BrdUrdLI ≤ 8.5 % were considered as slowly proliferating tumors . Clinical Assessment of Tumor Response Tumor size before RT was assessed basing on measures taken during rectoscopy , and endorectal sonography . Tumor regression after RT was assessed at the time of operation by surgeons according to the following Response Evaluation Criteria in Solid Tumors -LRB- RECIST -RRB- 18 : Complete response -LRB- CR -RRB- : 100 % disappearance ; partial response -LRB- PR -RRB- : 30 -- 99 % decrease ; stable disease -LRB- SD -RRB- : neither CR , PR or PD criteria met ; progression of disease -LRB- PD -RRB- : 20 % increase in sums of tumor longest diameters . Pathological Assessment of Tumor Response Tumor regression after RT was evaluated by a pathologist on the excised tumor mass . The following criteria of tumor regression assessed by Dworak et al. 19 were applied : D0 -- no regression ; D1 -- dominant tumor mass with obvious fibrosis and/or vasculopathy ; D2 -- dominantly fibrotic changes with few tumor cells or groups ; D3 -- very few -LRB- difficult to find microscopically -RRB- tumor cells in fibrotic tissue with or without mucous substance ; D4 -- no tumor cells , only fibrotic mass -LRB- total regression or response -RRB- . Statistical Methods Statistical analysis was performed with STATISTICA vs. 5 . Intergroup differences in the ordinal data were tested with ANOVA test or Student 's t test . P values of less than 0.05 were considered to indicate statistical significance . Linear regression was applied for assessing differences between fast and slowly proliferating tumors in relation with OTT , and its significance was determined by testing the difference between two correlation coefficients . Stratification by BrdUrd LI level was introduced and tested by the inclusion of dummy variable in the regression model . Results Patients A total of 92 patients were included in the study . Twenty-eight -LRB- 23.3 % -RRB- out of 120 patients initially qualified for this study were excluded from the analysis because of discontinuation of treatment , metastatic tumor noticed at operation , or no tumor samples taken for biological assessment during surgery . Mean age for the entire group of patients was 61.6 years -LRB- range 30 -- 75 -RRB- . There were 68 men and 24 women . There were no statistical differences between the two groups at the time of recruitment for prognostic factors such as : sex , age , histologic grade , or tumor stage -LRB- Table 1 -RRB- . Table 1Selected Characteristics of Patients and Treatment ParametersCharacteristicsSchedule ISchedule IITotalAge mean -LRB- ± SD -RRB- years -LRB- 38 -RRB- a 61.2 ± 12.0 -LRB- 54 -RRB- 61.9 ± 9.5 -LRB- 92 -RRB- 61.6 ± 10.6 Sex Male303868 Female81624Histological grade G162026 G2293463 G3303Tumor stage T181927 T2253055 T35510PTNM 1162541 28614 3131730 4123Interval between RT and surgery Mean -LRB- range -RRB- days -LRB- 38 -RRB- a 8.8 -LRB- 2 -- 14 -RRB- -LRB- 54 -RRB- 32.9 -LRB- 17 -- 45 -RRB- -LRB- 92 -RRB- 22.9 -LRB- 2 -- 45 -RRB- OTT mean -LRB- range -RRB- days -LRB- 38 -RRB- 13.8 -LRB- 7 -- 19 -RRB- -LRB- 54 -RRB- 37.9 -LRB- 22 -- 50 -RRB- -LRB- 92 -RRB- 27.9 -LRB- 7 -- 50 -RRB- Surgery Sphincter-preserving20 -LRB- 52.6 % -RRB- 31 -LRB- 57.4 % -RRB- 51 Abdominoperineal resection182341aNumber of patients In our series of patients , there were 27 stage 1 -LRB- 29.3 % -RRB- , 55 were T2 -LRB- 59.8 % -RRB- , and 10 were T3 -LRB- 10.9 % -RRB- . In 26 patients , tumor cells well differentiated -LRB- G1 -RRB- , 63 moderately differentiated -LRB- G2 -RRB- , and three poorly differentiated -LRB- G3 -RRB- -LRB- Table 1 -RRB- . Thirty-eight patients were treated according to schedule I , in which time interval between end of irradiation and surgery averaged 8.8 days -LRB- range 2 -- 14 ; Table 1 -RRB- . In 54 patients , schedule II was applied , in which mean break was 32.9 days -LRB- range 17 -- 45 -RRB- . Because the interval between RT and surgery appeared to be longer than planned , overall treatment time -LRB- OTT -RRB- , e.g. , time from the beginning of RT to surgery , was calculated and it appeared to be 7 -- 50 days -LRB- Table 1 -RRB- . Biologic , Pathologic , and Clinical Assessment of Tumor Response Mean BrdUrd LI before RT was 8.5 % -LRB- range 1.0 -- 24.2 % -RRB- and SPF was 22.0 % -LRB- range 3.8 -- 49.9 % -RRB- and the mean values did not differ between the two schedules -LRB- Table 2 -RRB- . Poorly differentiated tumors showed statistically significant higher BrdUrd LI than grades 1 and 2 tumors -LRB- P = 0.015 ; Table 3 -RRB- . After RT , tumors treated according to both schedules showed statistically significant growth inhibition -LRB- reduction of BrdUrd LI and percentage of SPF cells -RRB- in comparison with the values obtained before RT -LRB- Table 2 -RRB- . Radiation induced inhibition of tumor proliferation was expressed as a percentage of the after RT to before RT BrdUrd LI , and SPF as after/before RT percentage . This ratio ranged from 2.5 to 514 % for BrdUrd LI -LRB- Fig. 1 -RRB- and from 5.8 to 522.2 % for SPF . When we stratified patients into two groups according to their biological RT response , those radioresponsive with reduction of pretreatment values after radiotherapy above 50 % and those less responsive with reduction below 50 % , it appeared that the mean values -LRB- of the after/before RT ratios of BrdUrd LI and SPF -RRB- for the more radioresponsive tumors were significantly higher than for the less responsive ones . Therefore , these ratios were presented separately for fast -LRB- BrdUrd LI > 8.5 % , SPF > 22.0 % -RRB- and slowly -LRB- BrdUrd LI ≤ 8.5 % , SPF ≤ 22.0 % -RRB- proliferating tumors . Mean BrdUrd LI value after RT for fast proliferating tumors -LRB- 41 cases -RRB- showed statistically significant -LRB- P = 0.027 -RRB- reduced pretreatment percentage -LRB- 46.8 % -RRB- in comparison with slowly proliferating tumors -LRB- 85.3 % , 51 cases -RRB- . The same was true for SPF of fast -LRB- 56.4 % , 55 cases -RRB- and slowly -LRB- 113.8 % , 37 -RRB- proliferating tumors -LRB- P = 0.006 -RRB- . Table 2Status of Biological Parameters Before and After RTGroupBrdUrd LI -LRB- % -RRB- Mean -LRB- range -RRB- S-phase fraction -LRB- % -RRB- Mean -LRB- range -RRB- Apoptosis -LRB- % -RRB- Mean -LRB- range -RRB- All patientsBefore RT8 .5 -LRB- 1.0 -- 24.2 -RRB- 22.0 -LRB- 3.8 -- 49.9 -RRB- 5.9 -LRB- 0 -- 52.8 -RRB- After RT4 .1 * -LRB- 0.4 -- 18.3 -RRB- 16.8 ** -LRB- 1.5 -- 101.0 -RRB- 9.8 *** -LRB- 0 -- 45.9 -RRB- RT schedule IBefore RT8 .4 -LRB- 1.1 -- 24.2 -RRB- 21.5 -LRB- 6.1 -- 49.2 -RRB- 6.6 -LRB- 0 -- 32.4 -RRB- After RT3 .8 * -LRB- 0.8 -- 12.6 -RRB- 14.1 **** -LRB- 1.5 -- 47.9 -RRB- 10.5 -LRB- 0 -- 43.3 -RRB- RT schedule IIBefore RT8 .6 -LRB- 1.0 -- 20.0 -RRB- 22.3 -LRB- 3.8 -- 49.9 -RRB- 5.4 -LRB- 0 -- 52.8 -RRB- After RT4 .5 * -LRB- 0.4 -- 18.3 -RRB- 17.2 -LRB- 2.6 -- 101.0 -RRB- 9.5 ***** -LRB- 0 -- 45.9 -RRB- * P = 0.000 ** P = 0.015 *** P = 0.010 **** P = 0.002 ***** P = 0.042 Table 3The Relationship Between Tumor Biological Parameters and Histological GradeHistological gradeNBrdUrd LI -LRB- % -RRB- Mean -LRB- range -RRB- S-phase fraction -LRB- % -RRB- Mean -LRB- range -RRB- Apoptosis -LRB- % -RRB- Mean -LRB- range -RRB- G1268 .5 -LRB- 1.1 -- 17.1 -RRB- 23.7 -LRB- 5.8 -- 49.9 -RRB- 3.4 -LRB- 0 -- 32.4 -RRB- G2618 .2 -LRB- 1.0 -- 20.0 -RRB- 21.0 -LRB- 3.8 -- 45.6 -RRB- 7.2 -LRB- 0 -- 52.8 -RRB- G3316 .2 * , ** -LRB- 9.5 -- 24.2 -RRB- 27.7 -LRB- 18.9 -- 34.7 -RRB- 2.1 -LRB- 0.4 -- 4.8 -RRB- * P = 0.015 , difference between G1 and G3 ** P = 0.013 , difference between G2 and G3Figure 1The association between biological tumor response for slowly -LRB- BrdUrd LI ≤ 8.5 % ; closed symbol -RRB- and faster proliferating tumors -LRB- BrdUrd LI > 8.5 % ; open symbol -RRB- and overall treatment time . Insert shows linear regression performed separately for each of the tumor subgroups for OTT > 30 days . P value shows difference between two correlation coefficients . Next , the after/before RT ratios for BrdUrd LI and SPF were correlated with OTT . For SPF , statistical difference between linear regression coefficients for fast and slowly proliferating tumors was not obtained -LRB- P = 0.446 -RRB- , therefore the data for BrdUrd LI only are shown -LRB- Fig. 1 -RRB- . Insert on Fig. 1 shows a significant -LRB- P = 0.033 -RRB- difference in proliferation rate between fast and slowly proliferating tumors treated within OTT > 30 days . At that time slowly proliferating tumors , contrary to fast proliferating ones , show no inhibition but accelerated proliferation of tumor cells . This phenomenon was also confirmed by increased fraction of S-phase cells in tumors treated with longer RT schedule -LRB- Table 2 -RRB- . The influence of BrdUrdLI level has been also tested by the extended regression model between OTT and the percentage of after/before RT BrdUrd LI . BrdUrd LI level higher than 8.5 % has been coded as dummy variable . It appeared to be significant -LRB- P = 0.025 -RRB- in the relation between OTT and the percentage of after/before RT BrdUrd LI . The partial regression coefficient indicates that the average decrease of the percentage after/before RT BrdUrdLI for fast proliferating tumors -LRB- BrdUrd LI > 8.5 % -RRB- equals 39 % . All 92 irradiated rectal tumors were reviewed by the same pathologist -LRB- KN -RRB- . The tumors were classified according to the World Health Organization classification of intestinal carcinoma16 and staged according to the TNM classification20 . Of the 92 rectal tumors four had no pTNM classification , 41 were pT1 -LRB- 46.6 % -RRB- , 14 were pT2 -LRB- 15.9 % -RRB- , 30 were pT3 -LRB- 34.1 % -RRB- , and three were pT4 -LRB- 3.4 % -RRB- . Regional lymph node metastases were found in 27 -LRB- 30.7 % -RRB- patients , and 27 -LRB- 30.7 % -RRB- patients had their tumor down-staged . Pathologic assessment of tumor regression after RT according to classification described by Dworak19 was performed in 90 out of 92 patients -LRB- for two patients the assessment was impossible -RRB- . The analysis showed no tumor regression -LRB- D0 -RRB- in 18 -LRB- 20.0 % -RRB- tumors , dominant tumor mass -LRB- D1 -RRB- in 46 -LRB- 51.1 % -RRB- tumors , a few tumor cells in fibrotic mass -LRB- D2 -RRB- in 18 -LRB- 20.0 % -RRB- tumors , single tumor cells -LRB- D3 -RRB- in four -LRB- 4.4 % -RRB- , and no tumor cells were observed in four -LRB- 4.4 % -RRB- of the examined tumors -LRB- Fig. 2a -RRB- . In 25 -LRB- 27.8 % -RRB- out of 90 patients marked pathologic down-staging -LRB- no residual tumor confined to the rectal wall -RRB- was visible . Pretreatment BrdUrdLI and SPF were not correlated with early clinical and pathologic tumor response . However , patients having tumors with LI > 8.5 % were more radioresponsive -LRB- showed significant reduction in proliferative rate after radiotherapy -RRB- than patients with BrdUrdLI ≤ 8.5 % tumors , although statistically significant difference between the two tumor subgroups was seen only for D0 -- D1 grade -LRB- Fig. 2b -RRB- . Figure 2Association between biological and pathological assessment -LRB- Dworak classification -RRB- of early tumor regression for -LRB- A -RRB- total group of patients and -LRB- B -RRB- for slowly -LRB- BrdUrdLI ≤ 8.5 % -RRB- and fast proliferating -LRB- BrdUrdLI > 8.5 % -RRB- tumors . Mean values ± SE are shown . For stages D0 -- D1 , statistically significant lower inhibition of tumor cell proliferation after RT was observed for slowly than fast proliferating tumors . In the clinical assessment of tumor mass resected during surgery , 34 -LRB- 36.9 % -RRB- tumors showed stable disease , 12 -LRB- 13.0 % -RRB- showed progressive disease , 41 -LRB- 44.6 % -RRB- showed partial response , and four -LRB- 4.3 % -RRB- showed complete response -LRB- Fig. 3a -RRB- . And again , in fast proliferating tumors , greater inhibition in tumor proliferation rate -LRB- reduction of pretreatment BrdUrd LI value > 50 % -RRB- was observed in fast than in slowly proliferating tumors ; however , this difference was not statistically significant -LRB- Fig. 3b -RRB- . As the observed correlation between clinical assessment and SPF was weaker than for BrdUrd LI , the data were not shown . Partial and total tumor regression was observed in 45 -LRB- 48.9 % -RRB- tumors . However , tumor proliferation status was not in agreement with the kind of surgery . Sphincter-preserving surgery was performed in 51 out of 92 patients : in 22 -LRB- 23.9 % -RRB- fast proliferating and in 29 -LRB- 31.5 % -RRB- slowly proliferating tumors . Figure 3Association between biological and clinical assessment of early tumor regression after RT for all tumors -LRB- A -RRB- and separately for slowly and fast proliferating tumors -LRB- B -RRB- . Mean value ± SE are shown . Discussion This study provides evidence of a clinically significant biological effect of a short preoperative course of RT on tumor proliferation rate . The impact of irradiation on biological tumor response was assessed by BrdUrd LI , SPF , and the degree of subsequent pathologic and clinical down-staging of the tumors after surgery . The study showed differences in the pretreatment proliferation rate of the tumor . Mean BrdUrd LI before RT was equal to 8.5 % and ranged from 1 to 24.2 % . Mean SPF was 22.0 % and ranged from 3.8 to 49.9 % . The proportion of cells in S-phase as estimated by the DNA content overestimates the labeling index determined by the uptake of BrdUrd . This may be so because the exposure time is quite short and there may be subpopulations in the tumors that are synthesizing DNA at a very slow rate , or there may indeed be cells with an S-phase DNA content that are not synthesizing DNA -LRB- as a result of nutrient or oxygen supply , lack of growth factors , inadequate vascularity -RRB- . Mean value of the BrdUrd LI obtained in this study was lower than the one estimated by Bergstrom et al. 21 , Palmqvist et al. 22 , and Terry et al. 23 , and can be explained by a different method used by these authors : in vivo incorporation of iodouridine/bromodeoxyuridine , which can cause longer exposure of the tracers to S-phase cells . The differences in the LI value might be caused also by heterogeneity in proliferation within the tumor . It was shown by Bergstrom et al. 21 that rectal tumors are polarized , having the superficial surface toward the lumen of the gut and the other toward deep structures facing totally different environments . Apart from Bergstrom et al. , none of the above-mentioned authors gave account of site from where the tumor samples were taken . In each tumor analyzed by us , all the samples were taken from the same region , i.e. , the bottom part of the mass . In our study , pretreatment BrdUrd LI or SPF was not predictive for early clinical and pathologicl tumor response , probably because of different tumor microenvironment . However , BrdUrd LI after/before RT ratio gave information on the different significant biological processes that take place after irradiation , and have impact on cell death like redistribution , repopulation , and reoxygenation . BrdUrd LI after RT decreased to mean 4.1 % independently of the time interval between RT and surgery . Magnitude of LI reduction after RT was correlated with tumor proliferation rate . Greater reduction of BrdUrd LI value was observed in fast proliferating -LRB- LI > 8.5 % -RRB- tumors -LRB- to mean 46 % of the pretreatment value -RRB- than in slowly -LRB- LI ≤ 8.5 % -RRB- proliferating tumors -LRB- to mean 85.3 % of pretreatment value -RRB- . What then is the justification for better RT response of fast proliferating tumor cells ? According to current knowledge on tumor proliferation , radiation therapy should preferentially inactivate rapidly dividing cells , leaving behind a population biased toward slow proliferation . However , recruitment is a known effect of cytotoxic treatment , and new cells from quiescent cell populations are recruited into active proliferation after irradiation . Probably , slowly proliferating tumors might have greater propensity to recruit cells into rapid cycle in response to treatment than fast proliferating tumors , which might have little reserve capacity for further accelerating their cell cycle24 . That might be why we observed acceleration of proliferation rate in slowly proliferating tumors from 5 weeks after RT -LRB- basing on after/before RT BrdUrd LI ratio -RRB- , which followed temporary reduction of the number of DNA-synthesizing cells , 4 -- 5 weeks after the start of RT. . Accelerated proliferation was confirmed by increased S-phase fraction . However , better biological tumor responsiveness of fast proliferating tumors on cellular level did not find confirmation on tissue level that is in surgery because a fewer number of sphincter saving resections were performed in patients with fast -LRB- 22 -RRB- than those with slowly proliferating tumors -LRB- 29 -RRB- . Regression of rectal carcinoma after preoperative irradiation varies , likely reflecting differences in the physical and biologic properties of these tumors . Apart from biological characteristics discussed here , tumor down-staging depends on the total irradiation dose , the fractionation , and the interval between irradiation and surgery25 . We showed association of tumor proliferation rate after RT with tumor response basing on BrdUrd LI . SPF , considered as a less sensitive method of tumor proliferation , did not show such a correlation . The after/before radiotherapy BrdUrd LI ratios correlated , however nonsignificantly , with the degree of pathologic and clinical down-staging , which indicates that more radiation-induced cell death occurred in tumors that expressed high levels of BrUrd LI , or that an increased rate of tumor clearance occurred in more rapidly proliferating tumors . This effect was reflected by significantly higher incidence of apoptosis observed after RT only in fast proliferating tumors -LRB- 4.1 % vs 11.1 % ; P = 0.000 -RRB- . However , patients having tumors with LI > 8.5 % did not show higher rate -LRB- 11.2 % -RRB- of tumor pathological down-staging -LRB- D2 -- D4 -RRB- than patients with BrdUrd LI ≤ 8.5 % -LRB- 16.8 % -RRB- tumors , which may be suggestive of significant impact on tumor response also by biological processes other than proliferation . In the Spanish study26 , high proliferative activity of rectal cancer , as determined by PCNA immunostaining , was predictive of response to preoperative chemoradiotherapy . Willett et al. 27 , in the same tumor type treated with higher RT dose -LRB- 47 -- 52 Gy -RRB- and 5 FU , showed that patients having tumors with extensive Ki-67 staining had also a higher rate of tumor down-staging -LRB- 36 % -RRB- 4 -- 6 weeks after treatment than patients with minimal to moderate Ki-67 staining tumors -LRB- 22 -- 23 % -RRB- . These authors show that elevated postirradiation tumor proliferative activity correlated strongly with improved survival28 . These authors , in contrast to our study , did not consider the proliferation profile of pre - and postirradiation for individual patients . The correlation of down-staging and higher survival rates was also found by other authors29 ,30 . In our study , even in totally regressed tumors -LRB- D4 -RRB- , the percentage of the after/before radiotherapy BrdUrd LI was about 50 % , which may not indicate tumor but normal cell proliferation , mainly a fraction of activated fibroblasts or cycling endothelial cells in capillaries high in colorectal carcinoma31 . Our study showed complete pathologic response -LRB- D4 -RRB- similar to that in a Norwegian study -LRB- 4.5 % -RRB- 32 , where histological tumor slides were analyzed after treatment with a dose of 31.5 Gy in 18 fractions and 2 -- 3 weeks interval between RT and surgery . However , it should be stressed that in this study , a high incidence -LRB- 31.3 % -RRB- of recurrences was observed at late follow-up . Our analysis showed that patients having fast proliferating tumors , as assessed by BrdUrdLI , experienced higher rates of regression than patients with slowly proliferating tumors , which could suggest a more frequent possibility of performing sphincter-preserving procedures in these tumors . However , this was not confirmed in surgical procedures . Therefore , we do not know yet if pretreatment BrdUrd LI assessment will be a good predictor for a locoregional failure . Berger et al. 25 , analyzing tumor sterilization after preoperative RT for rectal cancer , did not find a predictive factor for complete pathological response among such factors as age , sex , tumor stage , and pathologic grade . However , they found favorable influence of higher doses -LRB- > 44 Gy -RRB- on pathologic stage . There is no known optimal time for the interval between RT and surgery . The Swedish group keeps the interval at about a week ; however , in other institutions , using longer RT treatments and higher total dose , longer intervals -- 4 to 6 weeks were adopted14 ,25 . The main reason for a longer interval is tumor regression , which makes sphincter preservation possible . Similar to Francois et al14 , we observed higher clinical and pathologic response rate after longer interval between RT and surgery . However , these authors14 showed nonsignificantly better overall survival for patients treated with shorter interval . Withers and Haustermans33 estimated the interval between long course of fractionated RT -LRB- 40 -- 54 Gy -RRB- and surgery and stated that the interval is not critical to either local recurrence or distant metastases . The authors offered the following arguments : the tumor cells do not disseminate until the primary tumor is large enough to be clinically detectable -LRB- probably 80 % of patients whose rectal tumors have not metastasized to lymph nodes will be free of metastases -RRB- . Irradiation with a dose of 40 Gy in 2 Gy fractions -LRB- equivalent to 25 Gy in five fractions -RRB- reduces tumor cell survival by about six decades , e.g. , from 1010 to 104 cells . However , we have to remember that although the short overall treatment duration in the 25 Gy in five-fraction regimen provides a radiobiological advantage , this is a relatively low dose34 , which causes about a 66 % reduction in the rate of local recurrence11 . A retrospective analysis of published results of preoperative radiation therapy for rectal cancer showed that local control probability curves were displaced toward higher doses as the overall duration of preoperative radiation therapy was increased15 . Therefore , longer intervals between short RT schedule -LRB- 25 Gy -RRB- and surgery may be inappropriate in case of patients with incomplete resection -LRB- cut-through -RRB- of primary tumor , in whom the average subclinical cancer cell burden increases during long interval . Also , subclinical disease beyond the future surgical margins , may be a potential target for future recurrences . Longer intervals after short RT can be dangerous because of potential subclinical tumor , which may grow more quickly than primary tumor15 ,33 , the and risk of developing distant metastases . If we imply that moderately differentiated adenocarcinoma cells have different metastatic and proliferative activities from poorly differentiated cancer cells , which was shown by Taniyama et al35 , then we could have an indication to adjuvant chemotherapy for patients with differentiated tumors . The authors35 indicated that moderately differentiated cancer cells are associated with hematogenous metastases to the liver , and the loss of tubular formation of cancer cells in poorly differentiated tumors may be fundamentally related to lymph node metastases and infiltrative growth . Therefore , particularly in patients with moderately differentiated and slowly proliferating tumors , adjuvant chemotherapy could be suggested after OTT shorter than 4 weeks , to prevent developing metastases to the liver . In conclusion , our study shows that pretreatment BrdUrd LI or SPF were not predictive for early clinical and pathologic tumor response . After/before BrdUrd LI ratios showed inhibition of proliferation in responsive tumors , but this was not reflected in the number of sphincter preserving procedures performed . As 1 month after RT , accelerated proliferation of tumor cells is observed only in slowly proliferating tumors , we think that longer interval between RT and surgery is inadvisable . If late tumor response confirms that patients having tumors with increased proliferative activity have statistically significantly less recurrences and improved survival rates compared with patients with less proliferative tumors , then we will be able to suggest a prognostic factor for individual rectal cancer patient , and a basis for selection to postoperative adjuvant chemotherapy .

O O O O O O O B I I O O B O O O B I O O O O B I O O O O O B O O O O O O B I O O O B O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O B O B I O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O B O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O

brdurdli
proliferation rate
early tumor response
rectal cancer
radiotherapy


The

Extended

Learning

Curve

for

Laparoscopic

Fundoplication

A

Cohort

Analysis

Of

Consecutive

Cases

Many

studies

have

looked

at

the

learning

curve

associated

with

laparoscopic

Nissen

fundoplication

-LRB-

LNF

-RRB-

in

a

given

institution

This

study

looks

at

the

learning

curve

of

a

single

surgeon

with

a

large

cohort

of

patients

over

a

period

Prospective

data

were

collected

on

patients

undergoing

laparoscopic

fundoplication

for

over

years

The

patients

were

grouped

consecutively

into

cohorts

of

patients

The

operating

time

the

length

of

postoperative

hospital

stay

the

conversion

rate

to

open

operation

the

postoperative

dilatation

rate

and

the

reoperation

rate

were

analyzed

Results

showed

that

the

mean

length

of

operative

time

decreased

from

min

in

the

first

patients

to

min

in

the

last

patients

The

mean

postoperative

length

of

hospital

stay

decreased

from

days

initially

to

days

latterly

There

was

a

conversion

to

open

operation

rate

in

the

first

cohort

compared

with

a

rate

in

the

last

cohort

Fourteen

percent

of

patients

required

reoperation

in

the

first

cohort

and

in

the

last

cohort

Sixteen

percent

required

postoperative

dilatation

in

the

first

cohort

of

the

last

patients

required

dilatation

In

conclusion

laparoscopic

fundoplication

is

a

safe

and

effective

operation

for

patients

with

gastroesophageal

reflux

disease

New

techniques

and

better

instrumentation

were

introduced

in

the

early

era

of

LNF

The

learning

curve

however

continues

well

beyond

the

first

patients

Introduction

It

is

well

known

that

there

is

a

learning

curve

associated

with

laparoscopic

Nissen

fundoplication

-LRB-

LNF

-RRB-

for

gastroesophageal

reflux

disease

-LRB-

GERD

-RRB-

A

number

of

studies

have

shown

a

decrease

in

the

number

of

complications

with

surgical

experience

and

with

modifications

to

the

surgical

technique

of

fundoplication

over

time

Watson

et

al.

showed

that

the

individual

surgeon

's

complication

rate

and

conversion

rate

were

highest

in

the

first

five

procedures

and

stabilized

after

the

first

operations

There

are

however

few

studies

with

large

patient

numbers

showing

the

learning

curve

of

a

single

surgeon

and

his/her

trainees

We

have

evaluated

this

learning

curve

in

our

series

of

consecutive

patients

undergoing

laparoscopic

fundoplication

Materials

and

Methods

Between

January

and

August

patients

-LRB-

males

females

-RRB-

-LSB-

mean

age

years

-LRB-

range

-RRB-

-RSB-

underwent

laparoscopic

fundoplication

in

a

District

General

Hospital

All

procedures

were

performed

or

supervised

by

a

dedicated

upper

gastrointestinal

surgeon

Several

trainees

became

the

primary

surgeons

later

in

the

series

under

direct

supervision

once

they

were

deemed

to

have

the

appropriate

laparoscopic

skills

The

indications

for

operation

were

symptomatic

GERD

despite

prolonged

medical

therapy

intolerance

of

medical

therapy

due

to

side

effects

and

volume

regurgitation

or

patient

preference

for

surgery

Data

were

collected

prospectively

on

a

handheld

computer

database

-LRB-

Psion

Psion

Ltd.

England

-RRB-

All

patients

underwent

preoperative

endoscopy

and

h

ambulatory

esophageal

pH

monitoring

After

the

first

cases

all

patients

also

underwent

stationary

esophageal

manometry

using

a

standardized

technique

The

operative

technique

was

modified

during

the

course

of

the

study

as

new

equipment

became

available

Initially

five

abdominal

ports

were

used

toward

the

latter

half

of

the

study

two

and

three

ports

were

used

For

the

first

patients

a

laparoscope

was

used

all

subsequent

operations

were

carried

out

using

a

laparoscope

The

lower

esophagus

was

mobilized

from

the

crural

arch

All

patients

underwent

division

of

the

short

gastric

vessels

initially

using

individually

applied

ligaclips

after

case

a

harmonic

scalpel

-LRB-

Ethicon

Endosurgery

UK

-RRB-

was

used

In

the

first

patients

the

crura

were

repaired

-LRB-

using

silk

-RRB-

only

if

a

hiatal

defect

and

a

hernia

were

present

After

this

all

patients

underwent

crural

approximation

A

loose

wrap

of

cm

length

was

constructed

over

a

French

gauge

bougie

using

nonabsorbable

sutures

-LRB-

initially

silk

later

Ethibond

-RRB-

incorporating

the

anterior

esophagus

During

the

period

of

the

study

patients

who

were

included

in

the

fourth

to

seventh

cohorts

underwent

a

laparoscopic

partial

posterior

fundoplication

as

part

of

a

randomized

trial

These

patients

were

included

in

this

study

as

there

was

no

difference

in

symptomatic

outcome

complication

rate

or

operative

time

between

this

group

and

those

undergoing

a

fundoplication

Fourteen

pediatric

patients

underwent

an

LNF

throughout

the

series

The

surgical

technique

used

was

the

same

in

adult

and

pediatric

populations

Patients

were

encouraged

to

mobilize

immediately

and

commenced

on

oral

fluids

followed

by

a

light

diet

as

soon

as

tolerated

The

overall

patient

group

was

divided

into

eight

cohorts

of

consecutive

patients

These

cohorts

were

analyzed

separately

to

compare

the

following

-LRB-

-RRB-

patient

demographics

-LRB-

-RRB-

preoperative

symptom

length

-LRB-

-RRB-

operative

time

-LRB-

-RRB-

length

of

postoperative

hospital

stay

-LRB-

-RRB-

conversion

to

open

operation

-LRB-

-RRB-

reoperation

rate

-LRB-

-RRB-

postoperative

dilatation

rate

and

-LRB-

-RRB-

perioperative

mortality

or

other

early

-LRB-

within

months

-RRB-

postoperative

complications

Results

The

mean

age

weight

and

length

of

preoperative

symptoms

for

each

group

was

similar

-LRB-

see

Table

-RRB-

This

table

also

shows

an

overall

decrease

in

the

amount

of

time

to

accrue

each

cohort

throughout

the

study

period

There

was

a

steady

decrease

in

the

mean

operative

time

throughout

the

study

period

from

min

in

the

first

cohort

to

min

in

the

last

cohort

-LRB-

Fig.

-RRB-

The

mean

postoperative

hospital

stay

was

reduced

from

days

-LRB-

range

-RRB-

to

days

-LRB-

range

-RRB-

from

the

first

to

the

last

cohort

There

were

no

perioperative

deaths

Table

and

Length

of

Preoperative

Symptoms

in

Patients

Undergoing

Fundoplication

for

GERD

Patient

period

to

accrue

cohort

-LRB-

months

-RRB-

age

-LRB-

years

-RRB-

-LRB-

range

-RRB-

-LRB-

-RRB-

-LRB-

-RRB-

-LRB-

-RRB-

-LRB-

-RRB-

-LRB-

-RRB-

-LRB-

-RRB-

-LRB-

-RRB-

-LRB-

-RRB-

Sex

-LRB-

M

F

-RRB-

34:1638:1228:2232:1829:2129:2134:1635:15

Mean

weight

-LRB-

kg

-RRB-

-LRB-

range

-RRB-

-LRB-

-RRB-

-LRB-

-RRB-

-LRB-

-RRB-

-LRB-

-RRB-

-LRB-

-RRB-

-LRB-

-RRB-

-LRB-

-RRB-

-LRB-

-RRB-

Mean

preoperative

symptomatic

period

-LRB-

months

-RRB-

-LRB-

range

-RRB-

-LRB-

-RRB-

-LRB-

-RRB-

-LRB-

-RRB-

-LRB-

-RRB-

-LRB-

-RRB-

-LRB-

-RRB-

-LRB-

-RRB-

-LRB-

-RRB-

Figure

operative

conversions

to

open

procedure

rates

of

reoperation

and

rates

of

dilatation

in

patients

undergoing

laparoscopic

fundoplication

for

GERD

Figure

also

shows

the

rate

of

conversion

from

laparoscopic

to

open

fundoplication

the

reoperation

rate

and

the

postoperative

dilatation

rate

Conversions

to

Open

Operation

The

conversion

rate

in

the

first

cohort

of

patients

was

Compared

to

this

only

one

conversion

was

required

in

the

last

patients

in

the

series

and

this

was

necessitated

by

equipment

failure

rather

than

surgical

difficulties

Other

conversions

were

undertaken

for

hemorrhage

from

short

gastric

vessels

-LRB-

seven

patients

-RRB-

port-site

bleeding

-LRB-

one

patient

-RRB-

splenic

bleeding

-LRB-

one

patient

-RRB-

difficult

access

-LRB-

two

patient

-RRB-

instrumental

esophageal

perforation

-LRB-

one

patient

-RRB-

and

adhesions

from

previous

surgery

-LRB-

two

patients

-RRB-

Patients

Needing

Postoperative

Dilatations

In

the

first

patients

of

them

-LRB-

-RRB-

needed

endoscopic

balloon

dilatation

for

persistent

dysphagia

or

gas

bloat

syndrome

between

days

and

months

postoperatively

They

were

dilated

between

one

and

three

times

Nine

patients

-LRB-

-RRB-

were

dilated

in

the

second

cohort

between

days

and

months

postoperatively

on

one

to

four

occasions

In

the

third

cohort

six

patients

-LRB-

-RRB-

underwent

dilatation

between

week

and

months

whereas

in

the

fourth

cohort

five

patients

-LRB-

-RRB-

were

dilated

between

weeks

and

months

postoperatively

They

were

all

dilated

once

or

twice

Two

patients

-LRB-

-RRB-

had

two

dilatations

each

between

and

months

in

the

fifth

cohort

No

dilatations

were

needed

by

the

last

patients

to

undergo

laparoscopic

fundoplication

Patients

Needing

Reoperation

Figure

illustrates

a

decline

in

the

number

of

patients

requiring

reoperation

from

seven

patients

-LRB-

-RRB-

in

the

first

to

three

patients

-LRB-

-RRB-

in

the

last

patients

Table

shows

the

number

of

reoperations

that

took

place

for

any

given

reason

in

our

overall

patient

group

It

also

highlights

the

number

of

reoperations

that

occurred

within

months

of

the

original

fundoplication

Table

Number

and

Timing

of

Patients

Undergoing

Reoperation

after

Laparoscopic

FundoplicationCause

of

ReoperationTotal

Number

of

patientsEarly

-LRB-

within

months

-RRB-

Late

-LRB-

after

months

-RRB-

Mediastinal

wrap

despite

of

In

the

first

cohort

five

patients

underwent

reoperation

for

mediastinal

wrap

herniation

between

and

months

postoperatively

Two

patients

required

revisional

surgery

one

underwent

a

Watson

fundoplication

whereas

the

other

undertook

a

redo

Nissen

fundoplication

at

and

months

respectively

for

persistent

dysphagia

failing

to

respond

to

endoscopic

dilatations

One

reoperation

for

wrap

herniation

was

attempted

laparoscopically

but

was

converted

to

an

open

procedure

All

other

reoperations

were

carried

out

as

open

procedures

In

the

second

cohort

three

patients

were

reoperated

on

for

mediastinal

wrap

herniation

and

wrap

disruption

at

and

months

postoperatively

one

by

open

surgery

and

two

laparoscopically

One

patient

underwent

laparoscopic

conversion

of

a

to

wrap

for

gas

bloat

at

months

despite

two

endoscopic

wrap

dilatations

There

was

one

reoperation

in

the

third

cohort

of

patients

for

gas

bloat

months

later

The

wrap

was

found

to

be

mildly

attenuated

and

was

taken

down

laparoscopically

In

the

fourth

cohort

one

patient

underwent

laparoscopic

conversion

to

a

wrap

for

gas

bloat

syndrome

months

later

and

one

patient

was

converted

from

a

to

a

wrap

for

a

persistent

reflux

Two

patients

underwent

open

reoperations

in

the

fifth

cohort

one

for

a

perforation

of

the

wrap

at

days

the

other

for

a

port-site

hernia

repair

at

months

In

the

sixth

cohort

two

patients

underwent

a

redo

LNF

for

wrap

herniation

and

disruption

at

and

months

postoperatively

In

the

seventh

cohort

two

patients

were

found

to

have

a

wrap

herniation

and

one

patient

was

found

to

have

a

large

crural

defect

with

wrap

herniation

at

and

months

respectively

All

underwent

redo

LNF

the

patient

with

the

large

crural

defect

had

a

hiatal

mesh

placed

In

the

last

cohort

three

patients

underwent

redo

LNF

-LRB-

two

with

hiatal

mesh

placement

-RRB-

for

wrap

herniation

at

and

months

postoperatively

Discussion

The

postoperative

complications

most

commonly

associated

with

open

fundoplication

are

dysphagia

and

gas

bloat

syndrome

The

advent

of

the

laparoscopic

approach

to

fundoplication

first

described

in

has

introduced

a

number

of

procedure-specific

complications

including

pneumothorax

pneumomediastinum

major-vessel

injury

mesenteric

thrombosis

and

gastrointestinal

perforation

The

first

prospective

randomized

study

comparing

laparoscopic

and

open

Nissen

showed

similar

complication

rates

and

a

better

symptom

outcome

in

those

who

had

undergone

laparoscopic

surgery

There

has

however

been

a

concern

as

to

the

severity

of

the

reported

complications

in

the

laparoscopic

approach

Before

the

commencement

of

this

study

the

surgeon

had

a

experience

with

open

fundoplications

In

the

early

formal

courses

were

not

available

to

learn

laparoscopic

fundoplication

consequently

the

surgeons

pioneering

this

procedure

were

mentored

for

the

first

few

cases

After

this

the

surgeon

would

operate

independently

Our

study

shows

that

as

the

surgeon

's

experience

of

laparoscopic

fundoplication

increases

the

mean

operating

time

becomes

comparable

to

that

of

an

open

operation

The

mean

postoperative

length

of

stay

in

hospital

was

days

in

the

last

patients

compared

with

an

average

stay

of

days

in

those

having

an

open

fundoplication

The

decrease

in

postoperative

length

of

stay

in

hospital

which

was

seen

throughout

this

series

can

be

partly

attributed

to

increased

knowledge

of

recovery

from

laparoscopic

procedures

and

from

patient

feedback

of

their

postoperative

recovery

The

high

conversion

rate

to

an

open

operation

in

our

first

patients

-LRB-

-RRB-

can

be

attributed

to

the

surgical

learning

curve

and

poorer

quality

equipment

leading

to

reduced

quality

of

vision

and

the

reduced

ability

to

secure

bleeding

Similarly

high

conversion

rates

were

seen

in

other

early

laparoscopic

series

Only

of

the

last

patients

needed

conversion

to

an

open

procedure

and

this

was

due

to

equipment

failure

One

patient

underwent

a

splenectomy

-LRB-

of

all

patients

-RRB-

due

to

splenic

bleeding

which

is

comparable

to

other

studies

This

compares

with

a

splenectomy

rate

of

in

open

Nissen

fundoplications

in

one

study

Of

the

patients

requiring

conversion

throughout

the

series

were

in

the

preharmonic

scalpel

era

Nine

of

these

were

converted

due

to

bleeding

The

harmonic

scalpel

has

greatly

enhanced

the

ease

of

fundal

mobilization

in

comparison

to

the

application

of

individual

ligaclips

to

the

short

gastric

arteries

A

decreasing

trend

in

conversion

rate

can

however

be

seen

within

the

first

four

cohorts

before

the

introduction

of

the

harmonic

scalpel

The

number

of

patients

undergoing

endoscopic

dilatation

decreased

significantly

from

in

the

first

patients

to

in

the

last

patients

This

was

probably

due

to

a

number

of

factors

First

of

the

last

patients

had

symptomatic

wrap

disruptions/slippages

causing

dysphagia

The

patients

who

were

found

to

have

wrap

herniation

presented

with

heartburn

and

not

dysphagia

Secondly

it

is

now

recognized

that

early

dysphagia

-LRB-

less

than

months

postoperatively

-RRB-

is

present

in

a

significant

proportion

of

patients

but

settles

with

time

without

the

need

for

intervention

The

exception

to

this

is

in

children

who

are

less

tolerant

of

dysphagia

after

laparoscopic

fundoplication

and

hence

are

more

likely

to

require

early

endoscopic

dilatation

Two

have

shown

dilatation

success

rates

of

and

respectively

in

resolving

postfundoplication

dysphagia

The

study

by

Malhi-Chowla

et

al.

also

found

that

the

only

symptom

that

responded

to

dilatation

was

dysphagia

Throughout

the

series

two

patients

had

been

reoperated

on

for

persistent

dysphagia

beyond

months

Both

were

in

the

first

cases

and

both

were

found

to

have

bowstringing

of

the

wrap

due

to

lack

of

division

of

the

posterior

gastric

bands

One

was

converted

to

a

Watson

fundoplication

whereas

the

other

underwent

a

redo

Nissen

fundoplication

Our

low

incidence

of

dysphagia

may

be

in

part

due

to

the

laparoscopic

operation

used

Hunter

et

al.

showed

that

the

incidence

of

early

and

late

persistent

dysphagia

is

significantly

lower

in

both

LFNs

and

Toupet

fundoplications

than

in

Rosetti

Nissen

fundoplications

Two

patients

had

undergone

reoperation

for

gas

bloat

syndrome

both

were

converted

to

a

posterior

wrap

and

are

now

either

asymptomatic

or

mildly

symptomatic

All

patients

in

this

study

had

been

followed

up

for

a

minimum

of

years

Overall

of

our

patients

required

reoperation

because

principally

of

wrap

herniation

After

the

first

operations

a

routine

posterior

crural

approximation

was

carried

out

with

nonabsorbable

sutures

to

reduce

the

incidence

of

thoracic

wrap

migration

Two

have

emphasized

the

importance

of

a

crural

repair

in

reducing

the

incidence

of

postoperative

paraesophageal

hiatus

hernia

Basso

et

al.

have

proposed

a

mesh

repair

of

the

hiatus

to

prevent

wrap

migration

after

finding

that

in

several

reoperations

the

sutures

approximating

the

crura

had

cut

out

with

consequent

wrap

herniation

Paraesophageal

wrap

herniation

is

more

common

in

laparoscopic

than

in

open

fundoplication

Several

reasons

have

been

proposed

for

this

-LRB-

-RRB-

the

tendency

to

extend

esophageal

dissection

further

into

the

thorax

-LRB-

-RRB-

the

increased

risk

of

breaching

the

left

pleural

membrane

during

dissection

and

-LRB-

-RRB-

the

reduced

postoperative

pain

allowing

increased

abdominal

pressure

when

vomiting/coughing

in

the

laparoscopic

procedure

Wu

et

al.

found

that

routine

division

of

the

short

gastric

arteries

and

posterior

closure

of

the

crura

during

LNF

significantly

reduced

wrap

slippage/migration

This

is

the

procedure

that

we

have

undertaken

since

the

patient

Despite

of

this

of

the

last

patients

underwent

reoperation

-LRB-

all

for

heartburn

due

to

wrap

herniation

-RRB-

Smith

et

al.

have

also

concluded

that

wrap

herniation

is

now

the

most

common

mechanism

of

failure

requiring

a

redo

fundoplication

Of

the

eight

patients

reoperated

on

in

the

first

cohort

only

one

procedure

was

attempted

laparoscopically

All

reoperations

are

now

attempted

laparoscopically

where

possible

This

change

in

approach

has

occurred

with

increasing

laparoscopic

experience

Several

have

shown

that

laparoscopic

reoperations

are

not

only

possible

and

safe

but

also

produce

good

results

Several

have

now

shown

a

satisfaction

rate

at

follow-up

after

LNF

Our

own

on

patient

satisfaction

years

postlaparoscopic

fundoplication

revealed

that

once

over

the

initial

problem

of

early

postoperative

dysphagia

the

satisfaction

rate

was

Furthermore

remained

free

of

significant

reflux

symptoms

and

only

were

subsequently

taking

regular

antireflux

medication

This

has

changed

little

throughout

the

course

of

the

series

Our

results

show

a

decreasing

trend

in

operative

time

postoperative

hospital

stay

conversion

rate

postoperative

dilatation

rate

and

reoperation

rate

with

increasing

surgical

experience

and

improved

technology

Another

factor

in

this

improvement

may

be

due

to

the

increased

frequency

with

which

this

procedure

was

performed

with

time

Conclusion

Dysphagia

is

the

Achilles

heel

of

laparoscopic

antireflux

surgery

To

avoid

this

the

authors

have

routinely

divided

the

short

gastric

vessels

This

has

led

to

an

increased

rate

of

conversion

owing

to

hemorrhage

especially

during

the

period

when

individual

ligaclips

were

used

Short

gastric

vessel

division

may

in

addition

increase

the

rate

of

wrap

herniation

and

clip

or

thermal

injury

to

the

gastric

fundus

leading

to

perforation

The

high

rate

of

reintervention

in

the

first

two

cohorts

would

not

be

acceptable

a

decade

later

It

must

be

recognized

that

at

the

start

of

this

series

the

visual

acuity

of

the

optical

systems

and

the

quality

of

the

instrumentation

were

both

substantially

inferior

to

those

of

today

Furthermore

there

were

no

formal

training

courses

available

The

pioneers

of

advanced

laparoscopic

surgery

had

to

suffer

high

conversion

and

complication

rates

in

laparoscopic

cholecystectomy

antireflux

and

groin

hernia

surgery

When

introducing

complex

techniques

surgeons

tend

to

underestimate

the

learning

curve

both

of

themselves

and

of

their

institution

Only

by

maintaining

prospective

data

can

these

problems

be

identified

and

recognized

O O B I O O O O O O O O O O O O O O O O O B I O O B I I O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O B I O O B I I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O 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O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O

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