PURPOSE: To estimate the influence of prolonged @entity1161 ( @entity1161 ) on survival outcomes in @entity189 after continuous intensity-modulated radiation therapy. METHODS AND MATERIALS: Retrospectively review 321 @entity1 with @entity11408 treated between October 2009 and December 2010 and all of them underwent simultaneous accelerated intensity-modulated radiation therapy. The fractionated dose was 2-2.47 Gy/F (median 2.27 Gy), and the total dose for nasopharyngeal region was 64-74 Gy/ 28-33 fractions. The association of prolonged @entity1161 and treatment interruption with PFS, LRFS and DFFS were assessed by univariate analysis and multivariate analysis. Survival analyses were carried out using Kaplan-Meier methodology and the log-rank test was used to assess the difference. The Cox regression proportional hazard model was used for multivariate analyses and evaluating the prognostic parameters for PFS, LRFS and DFFS. RESULTS: Univariate analysis revealed no significant associations between prolonged @entity1161 and PFS, LRFS, DFFS when dichotomized using various cut-off values (all P>0.05). In multivariate analysis, @entity1161 (range, 36-63 days) as a continuous variable, had no influence on any survival outcome as well (P>0.05). T and N classification were independent prognostic factors for PFS, LRFS and DFFS (all P<0.05, except T classification for LRFS, P = 0.057). Age was an independent prognostic factor for PFS (hazard ratio [HR], 1.033; P = 0.008) and DFFS (HR, 1.032; P = 0.043). CONCLUSION: We conclude that no such association between survival outcomes and radiation treatment duration (range: 36-63 days) can be found in the present retrospective study, however, we have to remind that prolongation in treatment should be limited in clinical application and interruptions caused by any reason should be minimized as much as possible.

Effect of Prolonged Radiotherapy Treatment Time on Survival Outcomes after Intensity-Modulated Radiation Therapy in XXXX .

@entity1161 :: ('MESH:D011832', 'Disease') :: ['RTT', 'radiation treatment time'] @entity1 :: ('9606', 'Species') :: ['patients'] @entity189 :: ('MESH:D002277', 'Disease') :: ['nasopharyngeal carcinoma'] @entity11408 :: ('MESH:C538339', 'Disease') :: ['NPC']
@entity189 :: (MESH:D002277,Disease) :: ['Nasopharyngeal Carcinoma']
