bluuebunny/crossref_metadata_2025 huggingface dataset:
Clinical implications of muscle mass and quality in early-stage colorectal cancer (CRC).
Authors: Hopkins Jessica , Baracos Vickie E , Bigam David , Eurich Dean , Sawyer Michael B.
Published: January 2019

648

Background: Body composition has emerged as a potential prognostic factor for outcomes in early-stage CRC. Specifically, muscle mass and quality and visceral fat have been shown to be related to overall survival (OS) and disease-free survival (DFS). The objective of this study was to determine associations of sarcopenia, reduced skeletal muscle radiodensity (SMR) and visceral obesity (VO) with 5-year OS and DFS. Methods: Muscle and visceral fat at the time of diagnosis were quantified in a retrospective cohort of consecutive, early-stage CRC patients (pts), identified from a prospectively collected cancer database. Skeletal muscle area on computed tomography (CT) was measured and normalized by height (m2) in order to compare skeletal muscle index (SMI) between pts. Mean SMR and visceral fat area were measured. All parameters were analyzed using Kaplan-Meier curves and univariate Cox regression. Sarcopenia was defined as SMI < 41 cm2/m2 in females and < 43 cm2/m2 in males with BMI < 25 kg/m2 and < 53 cm2/m2 with BMI > 25 kg/m2. Reduced SMR was defined as < 41 HU if BMI < 25 kg/m2 and < 33 HU if BMI > 25 kg/m2. VO was defined as VAT > 160cm2 in males and > 80cm2 in females. Results: We identified 968 pts with available CTs and anthropometric data. Prevalence of sarcopenia was 44.5% in males and 59.6% in females. Myosteatosis was present in 60.9% of pts. The mean length of follow up was 5.0 years, with 254 patients developing recurrent disease and 351 deaths. Males with sarcopenia and myosteatosis had worse overall survival (HR, 0.69, p = 0.005; HR 0.49, p < 0.001) but no difference in DFS. Presence of VO was not associated with worse OS or DFS. There was no difference in OS for females with sarcopenia or VO, but myosteatosis predicted reduced OS (HR 0.53, p = 0.004). There was no difference in DFS for females by presence of sarcopenia, myosteatosis or VO. Conclusions: Body composition, specifically sarcopenia and myosteatosis, are highly prevalent in CRC pts treated with curative intent, and their presence is associated with reduced OS. Therefore, skeletal muscle mass and radiodensity are important prognostic factors in CRC outcomes, which are easily attained in a clinical setting.
Association of phosphatidylinositol 3-kinase (PI3K) pathway activation with increased immune checkpoint expression in colorectal cancer (CRC) patients.
Authors: Nusrat Maliha , Roszik Jason , Katkhuda Riham , Menter David , Raghav Kanwal Pratap Singh , Morris Van Karlyle , Sharma Padmanee , Allison James Patrick , Blando Jorge M , Maru Dipen M. , Overman Michael J. , Kopetz Scott
Published: January 2019

653

Background: PI3K pathway is a known modulator of anti-tumor immune response and is frequently activated in CRC through genetic alterations such as PTEN loss (PTENloss) and PIK3CA mutations (PIK3CAmut). This study aims to determine the impact of these alterations on immune cell infiltration, priming and activation in early stage CRC patients (pts). Methods: Immune infiltrates and checkpoints were evaluated using quantitative immunohistochemistry (IHC) on primary CRC (N = 59) for both center of tumor (CT) and invasive margin (IM). Pts were evaluated by presence or absence of either PTENloss or PIK3CAmut (collectively termed PI3K pathway alterations). Microsatellite unstable (MSI) and stable (MSS) tumors were analyzed separately. Clinicopathologic data was examined for potential associations with PI3K pathway alterations. Separately, mRNA data (Agilent) was obtained for immune related genes from an internal cohort with PTEN and PIK3CA annotation (N = 73). Results: 59 pts comprised IHC cohort (40 MSS, 19 MSI); 23 pts (39%) had PTENloss or PIK3CAmut. In Agilent cohort, 16 of 73 pts (22%) had PI3K pathway alterations. In MSS CRC, these alterations were more common in CMS1 (p = 0.03), on right side (p = 0.048) and with peritumoral lymphocytes (p = 0.031). MSS pts with PI3K pathway alterations had higher PD1 protein expression (p = 0.04), 2.1 and 2.3 times increased density of CD3+ (p = 0.01) and CD8+ (p = 0.04) cells respectively, and higher Granzyme B protein expression (p = 0.04) in the CT. These pts also had higher PDL1 gene expression (p = 0.046). MSS CRC pts with PIK3CAmut similarly had 2 times more PDL1 protein expression in epithelial cells of the IM (p = 0.01). Alternate checkpoints were also increased in pts with PI3K pathway alterations, including higher protein expression of LAG3 in CT (P = 0.046) and higher gene expression of CTLA4, TIM3, and TIGIT (P < 0.05 for all). Conclusions: PI3K pathway activated MSS CRC is associated with increased immune engagement, but also upregulation of key immune checkpoints in early stage tumors resulting in an ineffective immune response. Combination of PI3K pathway inhibition with immunotherapy merits investigation in this subset of pts.
Characterizing heterogeneity in KRAS mutant colorectal cancers (CRC) using cellular, mutation, and immune profiles.
Authors: Sadanandam Anguraj , Poudel Pawan , Fontana Elisa , Ragulan Chanthirika
Published: January 2019

657

Background: Approximately 30%-50% of CRC patients have KRAS mutation, and they are associated with lack of treatment response to anti-EGFR therapy. KRAS mutant CRCs are heterogeneous that not all mutant tumors are dependent on its downstream signaling. At this era of the search for therapeutic targets related to mutant KRAS, it is essential to understand the underlying heterogeneity in KRAS mutant metastatic CRCs with a goal of identifying personalized therapeutic vulnerabilities. To understand KRAS mutation further, in this study we classified KRAS mutant CRCs based on individual cell types in the normal colon crypt and associated them with PIK3CA mutations and interferon-gamma responsive signature. Methods: Publicly available RNAseq gene expression data from KRAS mutant samples were used. Classification of CRC samples into CRCassigner subtypes, KRAS mutation dependents/independent groups, and interferon gamma-responsive status was performed using published signatures. Results: CRC samples (n>200) with KRAS mutant and wild-type statuses were classified into all the five CRCAssigner subtypes (goblet-like, enterocyte, transit-amplifying, stem-like and inflammatory) that represent individual cell types in the normal colon crypt. Interestingly, goblet-like subtype was found to be enriched for KRAS mutation. Among those KRAS mutant CRCs from all the subtypes (n=61), goblet-like samples showed significant enrichment (false discovery rate <0.05; hypergeometric test) for KRAS dependent signature, whereas stem-like subtype showed KRAS independent signature. KRAS independent stem-like CRCs showed increased PIK3CA mutation and expression of interferon-gamma responsive genes compared to dependent CRCs. Conclusions: Overall, KRAS mutant CRCs are heterogeneous with differentiated subtype highly dependent on the mutation and its signalling pathway, whereas less differentiated/stem-like subtype CRCs are independent of the mutation. Also, the enrichment of PIK3CA mutation and interferon-gamma responsive genes mainly in KRAS independent CRC subtype present a potential opportunity to target them using combination immunotherapeutics.
The prognostic role of CpG island methylator phenotype in metastatic colorectal cancer.
Authors: Chen Kuo-Hsing , Lin Liang-In , Tseng Li-Hui , Lin Yu-Lin , Liau Jau-Yu , Tsai Jia-Huei , Liang Jin-Tung , Lin Been-Ren , Cheng Ann-Lii , Yeh Kun-Huei
Published: January 2019

667

Background: The prognostic role of CpG Island Methylator Phenotype (CIMP) in colorectal cancer (CRC) is still controversial, especially in metastatic CRC. Methods: We retrospectively analyzed the CpG island methylator phenotype (CIMP) in stage I to IV CRC specimens, which were diagnosed during 2005-2013. CIMP status was determined using a 5- gene MethyLight-based assay ( p16, MINT1, MINT2, MINT31, and MLH1). Tumors were designated as CIMP if 3 or more of 5 genes gave percent of methylated reference value ≧ 10. The clinicopatholoical characteristics, anti-cancer therapies, and the overall survival outcome were reviewed. Overall survival (OS) was compared between patients with CIMP CRC and those with non-CIMP CRC. Results: Among 450 patients with successfully determined CIMP status, 259 (57.56%) were male, 312 (70.31%) were stages I-III, 316 (70.69%) were left-sided CRC. In the survival analyses in stages I-IV patients, there was no significant difference in OS between those with or without CIMP (long rank test, p = 0.4526). Importantly, patients with metastatic CIMP CRC had poor OS than those with metastatic non-CIMP CRC (median survival, CIMP vs. non-CIMP: 1.36 vs. 3.11 years, log rank test, p = 0.0047). In a multivariate analysis, which adjusted prognostic variables such as: KRAS and BRAF mutations, microsatellite instability status, age, sex, grade, primary site, metastatic site number, chemotherapies and targeted therapies, CIMP remained an independent poor prognostic factor for OS (HR = 6.213, 95% confidence interval: 2.443 to 15.799, p = 0.0001) in metastatic CRC. In an exploratory analysis, there were more tumors with liver metastases at diagnosis in CIMP CRC than in non-CIMP CRC (94.4% vs. 71.3%, p = 0.0416). Conclusions: Our data demonstrated CIMP might independently predict poor survival in metastatic CRC in a large East Asian cohort.
Identification of biomarkers for TAS-102 efficacy in metastatic colorectal cancer patients based on preclinical analysis and clinical validation.
Authors: Suenaga Mitsukuni , Mashima Tetsuo , Kawata Naomi , Dan Shingo , Wakatsuki Takeru , Shinozaki Eiji , Ichimura Takashi , Ogura Mariko , Takahari Daisuke , Osumi Hiroki , Ota Yumiko , Chin Keisho , Seimiya Hiroyuki , Yamaguchi Kensei , Yamaguchi Toshiharu
Published: January 2019

669

Background: Trifluridine (FTD) incorporation into DNA is the main anti-tumor mechanism of action of TAS-102. We performed preclinical analysis and translational validation study to identify the candidate cytokines for TAS-102 efficacy in metastatic colorectal cancer (mCRC) patients (pts). Methods: As a first preclinical process, we selected candidate cytokines according to our transcriptomic and cell biological analysis. We then validated predictive value of the cytokines in mCRC pts receiving TAS-102 (discovery) and regorafenib (control). Blood samples were obtained at baseline (BL), before second cycle (2nd) and progressive disease (PD), and cytokine levels were measured using ELISA. The change patterns were defined as ‘increased’ or ‘decreased’ from BL. Results: 93 pts were included in this study: 67 received TAS-102 and 26 received regorafenib. Preclinical cDNA microarray analysis with colon cancer cell lines demonstrated marked changes in the RNA expression of interleukin-8, VEGF-A and epiregulin (EREG) after FTD treatment. Particularly, in preclinical model, EREG secretion was highly measured after FTD treatment in FTD-sensitive cells, while not in FTD-resistant cells. In the discovery cohort, increased EREG levels at 2nd showed trend toward longer PFS and OS than decreased changes (2.6 vs 2.3 mos, P= 0.096; 10.8 vs 6.2 mos, P= 0.091). Meanwhile, decreased EREG levels at PD were marginally associated with longer PFS and significantly with longer OS than increased (4.0 vs 2.3 mos, P= 0.130; 9.8 vs. 6.2 mos, P= 0.016). Combined analysis of EREG changes showed that pts with either increased at 2nd or decreased at PD had significantly longer PFS and OS compared to those with both decreased at 2nd and increased at PD (3.0 vs 2.0 mos, HR: 0.47, 95%CI: 0.24-0.93, P= 0.031; 10.8 vs 5.3 mos, HR: 0.30, 95%CI: 0.14-0.61, P= 0.001). The findings were confirmed in the multivariate analysis for OS (HR: 0.311, 95%CI: 0.15-0.66, P= 0.002), and no significant differences were observed in the control cohort. Conclusions: Our preclinical data-based translational validation study suggests that serum EREG levels may predict clinical outcome in mCRC pts receiving TAS-102.
Genomic landscapes of brain metastasis patients of colorectal cancer to reveal clinical potential of individualized therapies.
Authors: Sun Jing , Wang Cheng , Gu Yayun , Yu Jian , Hu Zhibin , Gu Yanhong
Published: January 2019

674

Background: Brain metastasis (BM) from colorectal cancer (CRC) is rare with 0.6-2.9% incidence rising in decades partly due to improved systemic treatment and prolonged survival. CRC patients had poor prognosis after BM because of lack of effective therapy. Commonly, only isolated BM of CRC patients are candidates for surgery and decisions for individualized therapies in patients with BM are often made according to primary-tumor biopsies, however, whether genomic features were similar in BMs and in primary CRC remained unknown. Thus, it is urgent to describe the molecular landscapes of BM genomics and to identify potentially clinically informative alterations. Methods: We conducted whole-exome sequencing on 15 “trios” of patient-matched brain metastases, primary CRC tumors, and adjacent-normal samples. Sequencing data processing and analysis were performed using pipeline of GATK best practice. Mutect2 algorithm were used to identify somatic substitutions in targeted exons. Clonal Evolution Suite was applied to evaluatecancer-cell fraction (CCF) for each mutation. Results: We identified 24,988 somatic mutations from CRC and their paired BM. In addition to the signature of age, we deciphered two mutational signatures, which was indicators of homologous recombination deficiency (HRD) and DNA mismatch repair deficiency (MMRD) respectively. The fraction of two signatures were significantly higher in BM than in primary CRC samples ( P< 0.001). Further analysis revealed BM-specific mutations (CCFBM= 1 and CCFPrimary< 0.5) in BRCA1 and BRCA2 and a significantly higher microsatellite instability status in BM patients ( P< 0.05). Additional BM-specific mutations were identified in genes from TARGET database for which somatic alterations have therapeutic or prognostic implications. We identified recurrent BM-specific mutations in voltage-gated sodium channel proteins ( SNC7A and SCN2A). Conclusions: It has been proved that patients with advanced HRD and MMRD are sensitive to PARP inhibitors and PD-1 blockade respectively. We provide new candidate targets for molecular therapies. Our findings provide new clinical potential for individualized therapies of BM patients of CRC.
Tumor sideness and mutational status: The potential effects on mCRC pts survival and treatment outcomes.
Authors: Sezer Emel , Eser Kadir , Onder Arif Hakan , Ozturk Banu
Published: January 2019

682

Background: The treatment of mCRC has been changed with identification of different clinical behaviour of right and left sided tumors. Right-sided primary was associated with high mutational burden, worse prognosis and poor anti-EGFR response. We aimed to investigate the association between tumor site and survival, mutational status and treatment outcome of mCRC pts. Methods: The data of mCRC pts in two-cancer center in South Anatolia were retrospectively analyzed. The effects of tumor sidedness, treatment, braf on survival of mCRC pts were investigated using the log rank test. The Kaplan- Meier survival estimates were calculated. Results: A total of 210 (F/M=128/82) pts were included to study. Median age was 59.5 (range: 23-88) years. Right and left-sided tumour rates were 45 (21.7%) and 153 (72.9%), respectively. Kras, nras and braf mutation rates were 32.9, 5.5 and 6.7 %, respectively. Median follow-up was 27.5 (range: 1.3-274.3) months. In the right-sided tumors, kras (52.5 vs. 33.8 %, p=0.0034) and braf (33.3 vs. 11.1%, p=0.022) mutation rates were more than left-sided ones. Median PFS (15.1 vs. 14.2 months) and OS (27.5 vs. 23.9 months) were higher in the pts with left-sided tumors, the difference was not significant. First line bevacizumab was used in 76 (55%) in left, 15 (36%) in right, anti-EGFR was used in 27 (20%) in left, 11 (25%) in right-sided tumors. According to tumor side, there was no significant survival difference between treatment arms. In the pts with left-sided tumors, median OS was 39.3 months with anti-EGFR, 27.3 months with bevacizumab. Right-sided primary was associated with worse survival. Median OS was similar between braf wild and mutant tumours. Conclusions: Our mutation rates were similar with the literature. Braf mutations were more frequent in right-side tumors. Right-sided primary was associated with poor prognosis. However, the survival difference was not significant. Best survival rates were found with first-line anti-EGFR treatment in the pts with left-sided tumors, but only 20% pts used anti-EGFR at first line in this group. Due to low anti-EGFR usage at first line, survival rates were similar between treatment arms.
Platinum deposition in skin as a possible mechanism for peripheral sensory neuropathy (PSN) in patients (pts) with colorectal cancer (CRC) following oxaliplatin-based therapy.
Authors: Cao Yanshuo , Chang Qing , Zhang Wenjiang , Ornatsky Olga , Chen Eric Xueyu
Published: January 2019

685

Background: Oxaliplatin plus fluorouracil (FOLFOX) is a standard treatment for CRC pts. One of the most common and dose-limiting side effects of oxaliplatin is PSN. The mechanism of this phenomenon is poorly understood. Previous studies suggested that higher serum platinum levels were related to more severe neuropathy in testicular cancer pts. Methods: CRC pts who completed adjuvant FOLFOX at least 6 months prior to enrollment are eligible. Baseline demographic and treatment information were collected. EORTC CIPN20 (with EORTC QLQ-C30) questionnaire was used for self-reported PSN symptom assessment. Peripheral blood samples were collected for total/free platinum concentrations using high-performance liquid chromatography with tandem mass spectrometry (HPLC/MS-MS). Skin biopsies were obtained from the lower leg of consented pts. Imaging mass cytometry (IMC) was used to visualize platinum deposition (195Pt) and intra-epidermal nerve fiber (IENF) (PGP9.5-154Sm) in formalin-fixed paraffin embedded (FFPE) skin biopsy samples stained with a metal-conjugated antibody cocktail. Results: Nine patients were enrolled. Median age was 51.8 yr (range: 34.5-69.4 yr); male/ female: 5/4; mean cumulative dose of oxaliplatin was 800.7 ± 188.2 mg/m2; median time from last dose of oxaliplatin to enrollment was 48 months (range: 7.2-65.6 months). The mean sensory score from CIPN20 was 15.4 ± 4.3 (range: 10-25). Platinum was undetectable in plasma samples collected from all 9 patients. In skin samples, IMC showed significant platinum depositions and IENF. Conclusions: Severity of PSN was not related to cumulative dose of oxaliplatin or interval from last dose of oxaliplatin. Although platinum was undetectable in plasma in these patients, platinum was readily detectable in skin biopsies up to 65.6 months post completion of FOLFOX. This is the first demonstration of platinum deposition in skin post oxaliplatin treatment and it provides a possible mechanism for oxaliplatin-induced PSN.
The prognostic impact of neutrophil to lymphocyte ratio in patients with recurrent or metastatic esophageal squamous cell carcinoma receiving immune checkpoint inhibitors.
Authors: Guo Jhe-Cyuan , Lin Chia-Chi , Huang Ta-Chen , Hsieh Min-Shu , Hsu Chih-Hung
Published: January 2019

69

Background: The study explored the prognostic impacts of clinical parameters including neutrophil to lymphocyte ratio (NLR) in recurrent/metastatic esophageal squamous cell carcinoma (R/M ESCC) patients receiving anti-programmed cell death protein-1 (PD-1)/PD ligand 1 (PD-L1)-based therapy. Methods: Thirty-eight patients were enrolled. Tumor response evaluation was made according to Response Evaluation Criteria in Solid Tumours 1.1, and the clinical benefit response (CBR) was defined as complete response, partial response or stable disease at least 6 months. Clinical factors were analyzed for their impacts on patients' overall survival (OS) and progression-free survival (PFS). Formalin-fixed, paraffin-embedded tissues from 8 patients were analyzed by NanoString nCounter Human PanCancer Immune Profiling (NanoString Technologies, Seattle, WA, US). Results: Twenty-six recurrent and 12 de novo metastatic ESCC patients were enrolled. The response rate is 11.8%, and the CBR rate was 21.1%. The median PFS and OS are 2.7 and 5.5 months, respectively. The CBR group has lower blood white blood cells (WBC) ( P = 0.029), monocytes (p = 0.003), and NLR (p = 0.005). In univariate analysis, WBC, neutrophils, and NLR were statistically associated with PFS; performance status (PS), disease extent, albumin, WBC, neutrophils, and NLR were statistically associated with OS. In multivariate analysis, NLR (p = 0.007) was statistically associated with PFS; PS (p = 0.029) and NLR (p = 0.050) were statistically associated with OS. On examining the immune-related genes in ESCC tissues’ microenvironment, the ratios of mast cells, neutrophils, and macrophages relative to tumor-infiltrating lymphocytes (TILs) have significantly lower in the CBR group than in the non-CBR group. Conclusions: High NLR was associated with inferior prognosis in R/M ESCC patients receiving anti-PD-1/PD-L1-based therapy. The increased ratio of neutrophil to TILs in the ESCC tumor microenvironment of non-CBR patients may suggest a mechanistic role of neutrophils in affecting the efficacy of anti-PD-1/PD-L1 therapy. (Supported by the grant of MOST 105-2314-B-002 -186 -MY3)
Next-generation expression analysis (NanoString) to develop prognostic and predictive gene signatures for patients with locally advanced rectal cancer treated with neoadjuvant chemoradiotherapy.
Authors: Milano Annalisa , Borro Marina , Pilozzi Emanuela , Montori Andrea , Mazzotta Marco , Lorenzon Laura , Caivano Donatella , Chiloiro Giuditta , Botticelli Andrea , Mazzuca Federica , Osti Mattia Falchetto , Simmaco Maurizio , Ruco Luigi , Valentini Vincenzo , Marchetti Paolo
Published: January 2019

700

Background: The standard of care for locally advanced rectal cancer (RC) is neoadjuvant chemoradiotherapy (CRT) with 5FU aimed to tumor downstaging prior to radical resection but there is a wide spectrum of responses to it, from none to complete. The aim of this project is to validate top candidate genes previously identified by microarray studies as prognostic and predictive classifiers of locally advanced RC, using the NanoString nCounter Platform. Methods: Two cohorts of RC patients were identified according to tumor regression grade (TRG) of AJCC Staging Manual (7th) system: 1) good prognosis: patients that after neoadjuvant CRT obtained TRG0 (complete response); 2) poor prognosis: patients with TRG1 (moderate response), patients with TRG2 (minimum response rate) and patients with TRG3 (poor response). Pre-treatment biopsies tissues from ten TRG0 patients (ID TRG0bio) and thirteen TRG1-3 patients (ID TRG1-3bio) were macro-dissected from FFPE sections, RNA isolated and used for expression profiling of a 305 genes custom code set consisting of 12 normalizer genes, 101 prognostic genes (markers of stemness, invasiveness, proliferation, drug-resistance), 192 predictive genes (involved in response to 5-FU, to radiation therapy and in the response to CRT). All samples were normalized using the geometric mean of the housekeeper genes. P-values were calculated by student’s t-test and was consider significance if was less than 0.05. Gene-specific RNA expression profiles were compared using Spearman's correlation. The heat map was generated using MeV 4.9.0. Results: When we compared TRG0bio to TRG1-3bio tissues, among the 305 genes assayed, changes in expression levels of 18 genes (SSB, GAPDH, TXNDC9, DUT, PKM, STAT1,SLC28A3, DAG1, TYMS, FERMT1, ARNT,SLC6A6, SMAD3, SCRN1, POU5F1, GNG4, PDRG1, ATP5E) were statistically significant. Conclusions: Results suggest that TRG0 RC is characterized by distinct molecular events compared TRG1-3 disease. Next steps will be: to amplify sample size, to understand signaling pathways of top differentially expressed genes and to validate prospectively our gene signature.
Timing of surgery following neoadjuvant chemoradiation in rectal cancer: A retrospective analysis from an academic medical center.
Authors: Chau Justin , Maliske Seth , Berg Daniel James , Bhatia Sudershan , Bellizzi Andrew , Byrn John , Ginader Timothy , Monga Varun
Published: January 2019

702

Background: Neoadjuvant chemoradiotherapy has been proven to achieve decreased local recurrence in rectal cancer with lower toxicity but data confirming the optimal timing of surgery following neoadjuvant cares is less robust. Methods: The University of Iowa Cancer Registry was queried to identify all patients with rectal cancer between 2000-2012. Individual records were reviewed for all patients with Stage II-III disease who received neoadjuvant chemoradiation. Primary endpoints were time interval from last day of chemoradiation to surgery (TI) and overall survival (OS). Secondary endpoints included hospital length of stay following surgery (LOS), intraoperative blood loss (BL), and major postoperative complication including infection, anastomotic failure, and thromboembolic event. Patient characteristics such as personal and family history of malignancy were studied, and treatment regimens including chemotherapy type, radiation technique and quality of resection were also compared. All postoperative pathology slides were reviewed for completeness of resection by a single pathologist. Univariate logistic regression analyses were used to study the association between TI and OS to help define the optimal interval. Results: 88 patients were identified with Stage II and III rectal cancer after imaging and endoscopic study. There was no significant association between OS and TI when comparing less than 8 weeks to greater than 8 weeks (p = 0.14) or when considering TI as a continuous variable (p = 0.99). There was no significant association between TI and surgical complications including BL (p = 0.60) or LOS (median = 7.00 days, p = 0.06), though patients undergoing pelvic exenteration experienced notably longer LOS (n = 4, mean 24.25 days, max 60 days). Conclusions: Our findings indicate that overall survival is not significantly impacted by longer intervals between chemoradiation and surgery. The incidence of major postoperative complication was rare but cost patients and the healthcare provider significant resources; thus, our results implicate potential benefits to treating some Stage II and III rectal cancers solely with chemoradiotherapy.
A novel 3-dimensional (3D) microfluidics device to model the tumor microenvironment (TME).
Authors: Krasnick Bradley A. , Bi Ye , Goedegebuure Maddy , Goedegebuure Peter S. , Shirure Venktesh S. , George Steven , Fields Ryan
Published: January 2019

704

Background: In vitro models of cancer have led to significant therapeutic advances. Despite the widespread use of in vitro tissue culture, the ability to directly evaluate human biology is limited by the inability to model the complex, 3D nature of the TME. We introduce a novel, microfluidic-based system of 3D human micro-tumors perfused with a network of human micro-vessels which could overcome the shortcomings of current in vitro systems. Methods: The micro-device was created by casting polydimethylsiloxane (PDMS) onto master molds, which are then bonded to a flat PDMS sheet using air plasma. Normal human lung fibroblasts (NHLF) and GFP labelled endothelial colony forming cell derived endothelial cells (EC-FCECs) were loaded in a fibrin gel at a 1:2 ratio into the central tissue chamber. Media was introduced through the microfluidic lines. The vascular network was developed with complete EGM2 media under nominal interstitial flow. Colorectal tumor cell lines labelled with mCherry were loaded to the side chambers on the seventh day after NHLF and EC loading. Bevacizumab or TGF- β were added on the second day after tumor cell loading. Results: Micro-vessels formed in the central chamber in 5-7 days after loading. The vessels were perfused with 70KDa fluorescent (red) dextran, and displayed intact vessel wall barrier. A suspension of a colorectal tumor cell line was loaded into the device side chambers, next to a fully developed vasculature. The tumor cells drove angiogenesis into the side chambers, and at the same time tumor began to migrate into the central chamber and within the vessel lumen. The angiogenesis induced by tumor cells can be pharmacologically inhibited, and the migration/ intravasation of tumor cells can be stimulated by TGF-β. Conclusions: Our novel micro-device system can be used as a functional in vitro system that can model the tumor micro-environment. This system has the advantage over current in vitro and in vivo systems in that it is high-throughput, rapid, cost-effective, and recreates many features of the 3D TME. We are currently expanding the platform to incorporate immune cells and designing a completely autologous system to test cancer immunotherapeutics.
Selecting patients with stage II/III colorectal cancer for 5-fluorouracil-based adjuvant chemotherapy using proteomic analysis.
Authors: Yan Dongyao , Hong Ji Hyung , Lee Hee Yeon , Byun Jae Ho , Cecchi Fabiola , Tian Yuan , Schwartz Sarit , An Eunkyung , Hembrough Todd A.
Published: January 2019

708

Background: 5-fluorouracil (5-FU) is a common adjuvant treatment for stage III and high-risk stage II colorectal cancer (CRC). However, about 20% of patients relapse within 48 months of treatment with 5-FU, even when combined with oxaliplatin. To improve patient selection, tumor biomarkers that predict sensitivity to 5-FU have been proposed. These include proteins involved in 5-FU activation or metabolism such as uridine-cytidine kinase 2 (UCK2) and thymidylate synthase (TYMS). We used multiplexed mass spectrometry to evaluate the utility these biomarkers in the archived tumor samples of patients with stage II/III CRC. Methods: Tumor samples were from 143 patients with stage II/III CRC who received adjuvant 5-FU, folinic acid, and oxaliplatin during 2000-2014; 83% of patients received 12 cycles and the others received ≤ 11 cycles. Tumor cells were microdissected and solubilized, and 67 candidate biomarkers were quantitated using mass spectrometry. Overall survival (OS) and relapse-free survival (RFS) were assessed using the Kaplan-Meier method and log-rank test. Protein expression by tumor stage, lymph node (LN) status, tumor sidedness was compared using the Student’s t-test. Results: Of 143 patients, 45 had recurrence and 98 patients did not. UCK2 was detected in all samples, ranging from 187 to 1606 attomoles per microgram of total protein (amol/µg). Patients with UCK2 expression above 335 amol/μg (n = 109) had significantly longer OS than patients with lower expression (n = 34; HR: 0.42; p= 0.009). There was no significant difference in RFS (HR: 0.6; p= 0.088). UCK2 expression did not differ by disease stage, LN metastasis status, or tumor sidedness. TYMS expression was not associated with survival in this cohort. Analysis of other biomarkers associated with response to 5-FU and platinum is in progress. Conclusions: In stage II/III CRC, UCK2 expression above 335 amol/μg identifies a subgroup of 5-FU-treated CRC patients with longer survival, suggesting that quantitated UCK2 has potential for use in selecting patients for treatment. These findings warrant validation in larger cohorts.
miR-15a regulation of endothelial radiation sensitivity in colorectal cancer.
Authors: Rana Shushan Rajesh , Espinosa Cristina , Ruhl Rebecca , Robinson Latroy , Thomas Charles R. , Anand Sudarshan
Published: January 2019

709

Background: Radiation dose escalation causes significant changes within the tumor microenvironment (TME) to enhance tumor cell death including altered microRNA (miR) levels. Among endothelial miRs, we identified miR-15a exhibits dose dependent differential regulation. miR-15a targets a key determinant of endothelial cell (EC) radiosensitivity, acid sphingomyelinase (SMPD1), an enzyme that drives rapid EC apoptosis via enhanced ceramide production. In colorectal cancer (CRC) (n = 182 patients), high miR-15a is associated with worse 5-year progression free and overall survival. miR-15a also affects immune function by promoting a pro-inflammatory TME milieu. We hypothesized miR-15a inhibition will increase tumor cell death through preservation of EC SMPD1, enhancing endothelial apoptosis and inflammatory cytokine upregulation. Methods: Using TaqMan Human miR panels, miRs were profiled in human umbilical vein ECs (HUVECs) after single 2 vs 20 Gy treatment. miR-target prediction programs identified miRs targeting SMPD1. In vitro gain and loss of function studies were performed with miR transfections in HUVECs and CT26 CRC cells. CXCL10 expression was measured by qRT-PCR. Caspase 1 activation was measured by a luminescence based assay. A CT26 syngeneic CRC flank murine model was used for in vivo miR-15a inhibitor assessment administered via tail vein injection unencapsulated or encapsulated in vascular-targeted 7C1 nanoparticles. Results: Among miRs targeting SMPD1, miR-15a exhibited the greatest differential change in HUVECs 6h post-IR between low and high dose radiation. Lower dose was associated with higher miR-15a and vice versa. Further, miR-15a levels inversely correlated with SMPD1. Exogenous miR-15a significantly decreased SMPD1 mRNA and protein. miR-15a inhibition decreased proliferation in both HUVECs and CT26 cells and increased apoptosis when combined with radiation. miR-15a inhibition increased endothelial CXCL10 expression and caspase-1 activation. Both systemic and vascular-targeted miR-15a inhibitor significantly diminished tumor growth in vivo. Conclusions: Our data suggests inhibition of vascular miR-15a is sufficient to decrease tumor growth likely due to rescue of endothelial SMPD1.
Influence of liposomal irinotecan (nal-IRI) and non-liposomal irinotecan, alone and in combination, on tumor growth and angiogenesis in colorectal cancer (CRC) models.
Authors: Larsen Annette K , Trindade Cristiano , Bouygues Anaïs , Louadj Lila K , Thouroude Sandrine K , Klinz Stephan G , Kalra Ashish , Henriques João , Chibaudel Benoist , De Gramont Aimery , Escargueil Alexandre E , Mesange Paul
Published: January 2019

711

Background: The long circulating liposomal irinotecan nal-IRI (MM-398/PEP02, Onivyde) is approved for treatment of metastatic pancreatic cancer after disease progression with gemcitabine-based therapy. Besides their direct cytotoxic activity, camptothecins are thought to inhibit tumor angiogenesis via downregulating hypoxia-inducible factor 1 leading to attenuation of VEGF expression. Due to different deposition kinetics, irinotecan HCl and nal-IRI are likely to show different activities in vivo suggesting that a combination of the two agents may optimize intratumoral exposure and improve treatment efficacy. Methods: The activities of nal-IRI, irinotecan and their combination were compared in three human CRC xenograft models with different sensitivity to SN-38, the active metabolite of irinotecan, in vitro. Nal-IRI was dosed at 5 mg/kg q7d, while irinotecan HCl was dosed at 25 mg/kg at days 1 and 2 q7d. The activity of different regimens on tumor cell viability, hypoxia markers and the microvascular density was determined by quantitative biomarker analysis. Results: The relative antitumor activity of nal-IRI was most pronounced in tumor models with natural or acquired irinotecan resistance. Combinations of nal-IRI with irinotecan HCl was significantly better than irinotecan HCl alone in all tumor models although nal-IRI only provided 10% additional irinotecan. The antitumor activity of nal-IRI and Irintecan HCl in combination was accompanied by up to two times more tumor cell death and a marked 3-7 fold reduction of the microvessel density. Despite the strong antiangiogenic effect resulting in tumor hypoxia, the increase in HIF1α and, to lesser degree, HIF2α, was relatively modest and VEGF signal intensity remained at 85-115% of control values. Conclusions: Our results suggest that both irinotecan HCl and nal-IRI can counteract the hypoxia-mediated increase of HIF1α in vivo as previously reported in vitro. Furthermore, the combination of the two formulations demonstrated significant efficacy benefits. A combination of irinotecan HCl and nal-IRI merits further clinical investigation.
Prognostic relevance of human papillomavirus infection in anal squamous cell carcinoma: Analysis of the National Cancer Database.
Authors: Jhaveri Jaymin , Rayfield Lael , Liu Yuan , Chowdhary Mudit , Cassidy Richard John , Madden Nicholas Andrew , Tanenbaum Daniel G , Abugideiri Mustafa , Gillespie Theresa Wicklin , Patel Pretesh R , Patel Kirtesh , Landry Jerome Carl
Published: January 2019

735

Background: To examine the prognostic relevance of human papillomavirus (HPV) infection for anal squamous cell carcinoma (ASCC) patients treated with chemoradiation in the National Cancer Database (NCDB). Methods: The 2014 NCDB was queried for non-metastatic, histologically confirmed, ASCC patients diagnosed between 2004 and 2013. Patients were required to have HPV status documented in order to be eligible. Patients were then stratified into two groups: HPV+ and HPV-. Univariate analysis was performed using the χ2 test for categorical covariates and ANOVA for numerical covariates. Multivariable analysis (MVA) was performed using Cox proportional hazard model for overall survival (OS). Hazard ratios (HR) and 95% confidence intervals (CI) were generated for each covariate. To minimize selection bias, propensity score (PS) weighting was implemented to balance OS related variables between the groups including: age, education level, stage, diagnosis year, insurance type, and agent of chemotherapy. Results: A total of 1,063 patients were eligible. Patients were stratified into HPV+ (n = 498, 46.8%) and HPV- (n = 565, 53.2%). After PS weighting, MVA for OS showed that for men, HPV infection was associated with better OS (HR 0.60, CI 0.38-0.96; p = 0.034). However, for women, HPV infection did not significantly influence survival (HR 1.47, CI 0.96-2.25; p = 0.074). Conclusions: To our knowledge, this is the largest patient series evaluating the impact of HPV infection on OS in patients with anal cancer. We found that HPV infection is associated with a statistically significant better survival for men with ASCC. In contrast, for women, HPV infection did not significantly influence survival.
Planned organ preservation for selected T2-3 rectal cancer: French experience using chemoradiotherapy and contact xray boost.
Authors: Gerard Jean-Pierre , Barbet Nicolas N. , Dejean Catherine , Evesque Ludovic , Benezery Karine , Coquard Regis , Chateau Yann , Gal Jocelyn , Doyen Jerome , François Eric
Published: January 2019

751

Background: The Lyon R96-02 randomized trial has demonstrated in T2-3 rectal cancer that external beam radiotherapy (EBRT) with Contact X Ray brachytherapy (CXB) boost was increasing clinical complete response, sphincter preservation and in early cases organ preservation. We report French experience in 3 radiotherapy departments using CXB boost with chemoradiotherapy (CRT) in early T2T3N0. Methods: Selection based on digital rectal examination, colonoscopy, MRI (and/or Endorectal-ultrasound). Inclusion : adenocarcinoma (distal, middle rectum), T2 T3a-b, tumor diameter ≤ 4cm, N0, M0. Treatment : CXB (80-110 Gy/3-4 fr) followed by CRT (CAP 50). Tumor response assess on week 14 : DRE, rigid rectoscopy and MRI. Clinical complete response (cCR) defined as no visible tumor, supple rectal wall and TRG 1-2 on MRI. In case of cCR a close surveillance or local excision was proposed. Results: Between 2002 -2016, 84 patients treated. Median age: 75 years, Male: 59, Female: 25. Operable patients: 69 (83%). T2 : 52, T3 : 32 (Lyon Villeurbanne : 16, Macon : 11, Nice : 57). Median follow-up time : 53 months. cCR was achieved in 94% of cases. Local excision performed in 17 patients (ypT0 : 16). At 4 years, the cancer specific survival was 82% [CI:96-70] and the local relapse rate 12% [CI: 2-22]. No isolated perirectal lymph node relapse observed. After 4 years, 3 more local relapses observed (4, 6, 7 years). Main late toxicity ( > 6 months after treatment) was rectal bleeding (radiation telangiectasia) which required plasma argon coagulation in 5 patients. No TME surgery was performed and organ preservation was achieved in all cases. Bowel function was good in 85% of patients (LARS score < 20). Conclusions: When combining CXB with CRT, rectal cancer T2T3a-b N0 ≤4cm achieve a high rate of cCR (≥85%) with organ preservation, good bowel function, low rate of local relapse ( < 15%) and low toxicity. As rectal adenocarcinoma is radioresistant, the treatment must use a CXB boost. Like anal squamous cell cancer, planned organ preservation can be proposed to operable patients. The ongoing European OPERA trial aims at bringing evidence to this option.
Outcomes for metastatic colorectal cancer (mCRC) based on microsatellite instability.
Authors: Price Timothy Jay , Karapetis Christos Stelios , Joanne Young , Roy Amitesh , Padbury Rob , Maddern Guy , Moore James , Piantadosi Cynthia , Roder David , Townsend Amanda Rose
Published: January 2019

759

Background: Microsatellite instability (MSI) has been associated with improved survival outcomes in early stage CRC. In stage IV disease, MSI represents only 3-5% of cases and currently the prognostic implications are less clear. There is however evolving evidence that treatment pathways should include anti-PD-1 antibodies given the encouraging results in heavily pre-treated MSI mCRC patients. We undertook an analysis of the South Australian mCRC population based registry to explore the relevance of MSI status in this population based registry. Methods: The registry was analysed to assess patient characteristics and survival outcomes comparing patients with MSI or microsatellite stable (MSS) disease. K-M survival analysis was used to assess OS. Results: 4359 patients are registered on the data base. 598 (14%) patients had been tested for MSI. 62 (10.1%) of these patients had demonstrable MSI. Patient characteristics and outcomes are summarized in the table. There are statistically higher rates of right sided primary, poorly differentiated pathology and BRAF mutation in the MSI group associated with a trend to reduced survival. Chemotherapy and biological therapy received in the MSI v MSS groups was as follows; 5FU 31% v 25%, 5FU/irinotecan 17% v 12%, 5FU/oxaliplatin 52% v 58%, bevacizumab 31% v 42%, anti-EGFR 0 v 4.6%. Conclusions: The patient characteristics of MSI mCRC are in keeping with those previously reported. MSI in this population based mCRC registry is not associated with a favorable outcome as seen in earlier stage disease compared to patients with MSS disease. The trend to poorer outcomes may support routine testing and potentially an alternate treatment pathway, which may include PD-1 inhibitors.[Table: see text]
Chemotherapy dose reductions in obese patients undergoing adjuvant chemotherapy for colorectal cancer: secondary analyses of trial data and the Greater Manchester and Cheshire Cancer Network Audit.
Authors: Srivastava Prakhar , Malcolmson Lee , Saunders Mark P. , Renehan Andrew
Published: January 2019

763

Background: In patients with stage II/III colorectal cancer receiving adjuvant chemotherapy, doses are calculated using body surface area (BSA) but often capped at BSA > 2.0. Dose capping might be a mechanism of reported poorer survival in obese patients. We aimed to investigate the different dosing schedules across BMI categories, using trial and ‘real world’ audit datasets, and determine its impact upon overall survival. Methods: Data was accessed for 1122 patients from the control arm of the MOSAIC trial (accessed via the Data Project Sphere) and 327 patients from the Greater Manchester and Cheshire Cancer Network (GMCCN) audit. Pearson’s χ2 and correlation coefficient were used to assess the relationship between BMI (expressed as normal, overweight and obese: and as continuous, respectively) and dose reductions. A multiple logistic regression model was constructed to compare the odds of receiving dose reductions in each BMI category. 4-year overall survival was calculated for each BMI category and dose status. Results: In MOSAIC, there were increasing dose reductions by BMI category: normal, 3%; overweight, 5%; and obese, 11%, with similar patterns in the GMCCN OxMdG group. Obese patients in MOSAIC and the GMCCN OxMdG group had 3- and 12-fold higher odds (OR = 3.4 and 12.5, CI = 1.6-7.0 and 2.0-78.1), respectively, of receiving dose reductions. However, these differences did not translate to differences in overall survival by BMI category or dose status. Conclusions: In our investigated datasets, there appears to be a relationship between increasing BMI and dose reductions, though it is modest and does not manifest as a detrimental influence on overall survival. Our findings agreed with other studies performed using stage IV cancer patients, although the relationship between increasing BMI and dose reductions is more prominent in patients with metastatic disease. Investigating other outcome measures such as cancer-specific survival and chemotherapy related toxicity is required for clarity.
Microsatellite instability and adjuvant chemotherapy in stage II colon cancer.
Authors: Koenig Julie L. , Lin Albert Y. , Pollom Erqi L. , Chang Daniel Tandel
Published: January 2019

767

Background: Randomized control trials and population-based studies have not demonstrated a definitive benefit for adjuvant chemotherapy in stage II colon cancers. Tumor side and microsatellite instability (MSI) have been proposed as prognostic and predictive factors, but there is little consensus about their utility. Previous studies have been limited by the availability of MSI data. Because microsatellite stability (MSS) is associated with worse prognosis and higher risk of metastases, we hypothesized patients with MSS would have increased benefit from chemotherapy. Methods: Using the National Cancer Database, we preformed a retrospective cohort study of patients with resected stage II colon cancer diagnosed 2006-2013. Patient and disease characteristics were compared with chi-square tests. Survival was evaluated with Cox proportional hazard models. Results: We identified 59,475 patients with stage II colon cancer. 11.4% of patients had known MSI status (n = 6,763) of which 88% had MSS (n = 5,953) and 12% had MSI (n = 810). Patients with MSS were more likely to receive chemotherapy (28.2% vs 19.9%, p < 0.001) and have left-sided tumors (38.8% vs 16.7%, p < 0.001). MSI (adjusted hazard ratio [HR] 0.64, 95% confidence interval [CI] 0.48-0.87; p = 0.003) and receipt of chemotherapy (HR 0.54, 95% CI 0.42-0.69; p < 0.001) were associated with better survival after controlling for multiple characteristics including tumor side. Although left-sided tumors had better survival on univariate analysis (HR 0.91, 95% CI 0.88-0.94; p < 0.001), side was not an independent predictor of survival after controlling for MSI and other characteristics (HR 1.01, 95% CI 0.86-1.20; p = 0.860). Among patients with MSS, chemotherapy remained associated with improved survival (HR 0.54, 95% CI 0.43-0.70; p < 0.001) and this benefit did not vary by tumor side (interaction p = 0.380). There was no interaction between MSI status and chemotherapy (p = 0.139), but we observed less of a survival benefit for chemotherapy in patients with MSI (HR 0.81, 95% CI 0.38-1.75; p = 0.595). Conclusions: Our data suggest a benefit for adjuvant chemotherapy in stage II colon cancer even after adjusting for MSI status. However, tumor side was not prognostic after controlling for MSI status.