A prognostic analysis of 895 cases of stage III colon cancer in different colon subsites

Prognostic and Predictive Determinants of Colorectal Cancer: A Comprehensive Review

Colorectal cancer (CRC) remains a significant global health burden, necessitating a thorough understanding of prognostic and predictive factors to enhance patient outcomes. This systematic review aims to comprehensively evaluate prognostic and predictive determinants in CRC, encompassing both traditional and emerging biomarkers. A systematic search of major electronic databases was conducted to identify relevant studies published from 1995 up to 2024. Eligible articles were critically appraised, and data extraction was performed according to predefined criteria. The prognostic determinants examined included clinicopathological features such as tumor stage, grade, and lymph node involvement, as well as molecular biomarkers including RAS, BRAF, and MSI status. Predictive determinants encompassed biomarkers influencing response to targeted therapies and immunotherapy, such as HER2 and Immunoscore. The review also explores novel prognostic and predictive markers, including tumor microenvironment characteristics and liquid biopsy-based biomarkers. Synthesizing evidence from diverse studies, this review provides insights into the prognostic and predictive landscape of CRC, highlighting the potential clinical implications of identified determinants. Understanding the multifaceted nature of prognostic and predictive factors in CRC is imperative for the advancement of personalized treatment strategies and improvement of patient outcomes.

Overall Survival, BRAF, RAS, and MSI Status in Patients Who Underwent Cetuximab After Refractory Chemotherapy for Metastatic Colorectal Cancer

PURPOSE

Evaluate overall survival (OS), RAS, BRAF, and MSI frequencies in patients with metastatic colorectal cancer (mCRC), refractory to chemotherapy, and finally treated with cetuximab.

METHODS

A retrospective cohort study to evaluate 211 mCRC patients with wild-type KRAS treated with cetuximab. BRAF V600E, KRAS, NRAS gene mutations, and MSI status were identified using PCR techniques in a population of pre-treated patients who were refractory to fluoropyrimidines, oxaliplatin, and irinotecan. In addition, we evaluated the mutation frequency of the BRAF and NRAS genes and the MSI status of this population. Uni- and multivariate analyses were performed for independent prognostic factors of OS.

RESULTS

The median OS was 10.4 months, 6.6 months for patients with right and 11.5 months for left colon cancers (p = 0.02). The frequencies of mutations were BRAF at 3.9% (median OS of 4.9 months), NRAS at 3.38% (median OS of 6.9 months), and MSI-High status at 3.3% (median OS of 4.6 months). The OS, NRAS, and MSI frequencies were similar to those found in other studies that evaluated cetuximab in poly-treated patients and were associated with lower survival rates in univariate analyses. The frequency of BRAF mutations was lower than that found in previous studies. The only variable that remained significant for OS in the multivariate model was tumour laterality, with patients with right colon cancer presenting a worse prognosis (HR = 2.81).

CONCLUSION

Although BRAF, NRAS mutations, and MSI-High status were associated with shorter OS in univariate analyses, only tumour laterality remained an independent prognostic factor in the multivariate analysis.

Primary tumor resection improves prognosis of unresectable carcinomas of the transverse colon including flexures with pulmonary metastasis: a cohort study

PURPOSE

Studies of unresectable colorectal cancer pulmonary metastasis (CRPM) have rarely analyzed patient prognosis from the perspective of colonic subsites. This study aimed to evaluate the effects of primary tumor resection (PTR) on the prognosis of patients with unresectable pulmonary metastases of transverse colon cancer pulmonary metastasis (UTCPM), hepatic flexure cancer pulmonary metastasis (UHFPM), and splenic flexure cancer pulmonary metastasis (USFPM).

METHODS

Patients were identified from the Surveillance, Epidemiology, and End Results database between 2000 and 2018. The Cox proportional hazards regression models were used to identify prognostic factors of overall survival (OS) and cause-specific survival (CSS). The Kaplan-Meier analyses and log-rank tests were conducted to assess the effectiveness of PTR on survival.

RESULTS

This study included 1294 patients: 419 with UHFPM, 636 with UTCPM, and 239 with USFPM. Survival analysis for OS and CSS in the PTR groups, showed that there were no statistical differences in the the UHFPM, UTCPM, and USFPM patients. There were statistical differences in the UHFPM, UTCPM, and USFPM patients for OS and CSS. Three non-PTR subgroups showed significant statistical differences for OS and CSS.

CONCLUSION

We confirmed the different survival rates of patients with UTCPM, UHFPM, and USFPM and proved for the first time that PTR could provide survival benefits for patients with unresectable CRPM from the perspective of the colonic subsites of the transverse colon, hepatic flexure, and splenic flexure.

Impact of primary tumor resection on the survival of patients with unresectable colon cancer liver metastasis at different colonic subsites: a propensity score matching analysis

OBJECTIVE

To investigate the effect of primary tumor resection (PTR) on the prognosis of patients with unresectable colon cancer liver metastasis (UCCLM) at seven colonic subsites using the Surveillance, Epidemiology, and End Results (SEER) database.

METHODS

Propensity score matching (PSM) was performed to balance selection bias using all available variables that could be of potential relevance. After matching, the groups were redefined in a 1:1 ratio using the nearest method. Cancer-specific survival (CSS) was compared among the patients of PTR and non-PTR groups. Cox regression models were used to identify the prognostic factors for CSS.

RESULTS

CSS was significantly different between all groups. Cox regression analysis showed that PTR was an independent prognostic factor for all groups. After PSM, PTR significantly prolonged CSS for all groups. Subgroup analysis showed that PTR did not improve the prognosis of N2 stage patients in the cecum, ascending colon, and descending colon groups; T1 + T2 stage patients in the hepatic flexure group; and patients with a tumor size ≤5 cm in the splenic flexure group. Segmental colectomy could prolong CSS of patients in the cecum, ascending colon, transverse colon, splenic flexure, and sigmoid colon groups, while extended colectomy could prolong CSS of patients in the hepatic flexure and descending colon groups.

CONCLUSION

At different colonic subsites, UCCLM patients had different CSS. PTR could improve their prognosis, however, N stage, T stage, and tumor size are important reference indicators. In addition to patients in the hepatic flexure and descending colon groups, we suggested that patients in other groups should choose segmental colectomy.

Prognostic role of detailed colorectal location and tumor molecular features: analyses of 13,101 colorectal cancer patients including 2994 early-onset cases

BACKGROUND

The pathogenic effect of colorectal tumor molecular features may be influenced by several factors, including those related to microbiota, inflammation, metabolism, and epigenetics, which may change along colorectal segments. We hypothesized that the prognostic association of colon cancer location might differ by tumor molecular characteristics.

METHODS

Utilizing a consortium dataset of 13,101 colorectal cancer cases, including 2994 early-onset cases, we conducted survival analyses of detailed tumor location stratified by statuses of microsatellite instability (MSI), CpG island methylator phenotype (CIMP), and KRAS and BRAF oncogenic mutation.

RESULTS

There was a statistically significant trend for better colon cancer-specific survival in relation to tumor location from the cecum to sigmoid colon (Ptrend = 0.002), excluding the rectum. The prognostic association of colon location differed by MSI status (Pinteraction = 0.001). Non-MSI-high tumors exhibited the cecum-to-sigmoid trend for better colon cancer-specific survival [Ptrend < 0.001; multivariable hazard ratio (HR) for the sigmoid colon (vs. cecum), 0.80; 95% confidence interval (CI) 0.70-0.92], whereas MSI-high tumors demonstrated a suggestive cecum-to-sigmoid trend for worse survival (Ptrend = 0.020; the corresponding HR, 2.13; 95% CI 1.15-3.92). The prognostic association of colon tumor location also differed by CIMP status (Pinteraction = 0.003) but not significantly by age, stage, or other features. Furthermore, MSI-high status was a favorable prognostic indicator in all stages.

CONCLUSIONS

Both detailed colonic location and tumor molecular features need to be accounted for colon cancer prognostication to advance precision medicine. Our study indicates the important role of large-scale studies to robustly examine detailed colonic subsites in molecular oncology research.

Endoscopic polypectomy for malignant polyps: Should tumor location (right versus left side) guide clinical decisions?

BACKGROUND

Current guidelines consider endoscopic resection appropriate treatment for malignant colon polyps with negative margins, low-grade histology, and no lymphovascular invasion. While increasing literature demonstrates a worse prognosis for advanced stage right- versus left-sided colon cancers after curative treatment, there is paucity of data regarding prognostic effect of location in patients undergoing endoscopic resection of T1 polyps. We hypothesized the more aggressive biologic behavior observed in advanced right-sided cancers would be similarly represented in malignant polyps, and this location would be associated with lower overall survival.

METHODS

The National Cancer Database was queried for adults with T1NxMx tumors who underwent endoscopic polypectomy (2004-2017). Patients with positive margins or without follow-up information were excluded.

RESULTS

A total of 2,337 patients met inclusion criteria; 22% had right-sided polyps. Endoscopically excised proximal tumors were more common in elderly, and those with public insurance and more comorbidities (all P < .01). Among patients with complete pathologic data, there were no statistical differences between right- and left-sided polyps with 1 cm median size, >92% without lymphovascular invasion, and 100% without tumor deposits. Univariate analysis showed 73% vs 86% 5-year overall survival for right versus left polyps (P < .01). After adjustment for available confounders, right-sided location remained significantly associated with worse overall survival (hazard ratio 1.49, 95% confidence interval 1.21-1.83).

CONCLUSION

In this national cohort of patients with endoscopically excised malignant polyps, we identified right colon location as an independent prognostic factor associated with increased risk of mortality. Our data suggest polyp location should be taken into consideration when making clinical decisions regarding treatment and/or surveillance.

Poorer Survival in Patients with Cecum Cancer Compared with Sigmoid Colon Cancer

Background and Objectives: An increasing number of studies have shown the influence of primary tumor location of colon cancer on prognosis, but the prognostic difference between colon cancers at different locations remains controversial. After comparing the prognostic differences between left-sided and right-sided colon cancer, the study subdivided left-sided and right-sided colon cancer into three parts, respectively, and explored which parts had the most significant prognostic differences, with the aim to further analyze the prognostic significance of primary locations of colon cancer. Materials and Methods: Clinicopathological data of patients with colon cancer who underwent radical surgery from the Surveillance, Epidemiology, and End Results Program database were analyzed. The data was divided into two groups (2004−2009 and 2010−2015) based on time intervals. Two tumor locations with the most significant survival difference were explored by using Cox regression analyses. The prognostic difference of the two locations was further verified in survival analyses after propensity score matching. Results: Patients with right-sided colon cancer had worse cancer-specific and overall survival compared to left-sided colon cancer. Survival difference between cecum cancer and sigmoid colon cancer was found to be the most significant among six tumor locations in both 2004−2009 and 2010−2015 time periods. After propensity score matching, multivariate analyses showed that cecum cancer was an independent unfavorable factor for cancer specific survival (HR [95% CI]: 1.11 [1.04−1.17], p = 0.001 for 2004−2009; HR [95% CI]: 1.23 [1.13−1.33], p < 0.001 for 2010−2015) and overall survival (HR [95% CI]: 1.09 [1.04−1.14], p < 0.001 for 2004−2009; HR [95% CI]: 1.09 [1.04−1.14], p < 0.001 for 2010−2015) compared to sigmoid colon cancer. Conclusions: The study indicates the prognosis of cecum cancer is worse than that of sigmoid colon. The current dichotomy model (right-sided vs. left-sided colon) may be inappropriate for the study of colon cancer.

Improvement in colorectal cancer outcomes over time is limited to patients with left-sided disease

PURPOSE

Incidence and mortality of colorectal cancer (CRC) declined over the last decades. However, survival depends on the primary tumor location. It is unknown if all progress in outcomes vary depending on left-sided (LCRC) versus right-sided (RCC) colorectal cancer. We compare incidence and mortality rates over time according to the primary tumor location.

METHODS

Data from the Austrian National Cancer Registry spanning from 1983 to 2018 were used to calculate annual incidence and mortality rates and survival stratified by primary tumor localization and stage. Joinpoint regression with linear regression models were used on different subgroups to identify significant changes of incidence- and mortality slopes.

RESULTS

A total of 168,260 (incidence dataset) and 87,355 cases (mortality dataset) were identified. Survival of disseminated RCC was worse compared to LCRC (HR 1.14; CI 1.106-1.169). Total and LCRC incidence and mortality rates declined steadily over time, whereas the rates of RCC did not. Incidence of disseminated RCC declined significantly less (slope - 0.07; CI - 0.086; - 0.055) than in LCRC (slope - 0.159; CI - 0.183; - 0.136); mortality rate of RCC was unchanged over time. Incidence and mortality of localized RCC remained unchanged over time, whereas both rates declined independently of stage in LCRC.

CONCLUSION

Colorectal cancer outcomes during the last 35 years have preferentially improved in LCRC but not in RCC, indicating that the progress made is limited to LCRC. It is necessary to define RCC as a distinct form of CRC and to focus on specific strategies for its early detection and treatment.

Predictive Value of the Prognostic Nutritional Index in Neoadjuvant Chemoradiotherapy for Rectal Cancer

BACKGROUND/AIM

Prognostic nutritional index (PNI) and neutrophil-to-lymphocyte ratio (NLR) indicate nutritional status and host immunity. We used immunohistochemistry and apparent diffusion coefficient (ADC) values calculated using diffusion-weighted imaging (DWI) to investigate relationships of these factors with pathological and radiological characteristics in rectal cancer treated with neoadjuvant chemoradiotherapy (nCRT).

PATIENTS AND METHODS

We evaluated expression levels of VEGFA, CD8, CD33, and ADC values in tumors pre/post nCRT; and analyzed the relationships between those factors and PNI, NLR in 32 patients.

RESULTS

Pretreatment PNI negatively correlated with change in tumor stromal CD8 ⁺ T cells and positively correlated with ADC values. Pretreatment NLR and PNI change correlated with recurrence-free survival (RFS).

CONCLUSION

Patients with higher pretreatment PNI had greater changes in ADC values and stromal CD8 ⁺ T-cell counts, and those with greater PNI reduction from nCRT had a worse prognosis. Proper nutritional management during nCRT benefits patients and may lead to better prognosis in rectal cancer.

Influence of first line chemotherapy strategy depending on primary tumor location in metastatic colorectal cancer

Background

Primary tumor location (PTL) is a major prognostic factor in metastatic colorectal cancer (mCRC) with left side which present better prognosis than right sided. Uncertainty exists regarding comparative effectiveness of irinotecan or oxaliplatin doublet in mCRC in function of PTL.

Methods

We conducted a retrospective comparing clinical outcomes from both regimens in function of sidedness. Patients with newly diagnosed mCRC candidates to first-line chemotherapy were selected. Clinical outcomes were assessed and stratified by tumor location (left, right and rectal) and type of treatment.

Results

Overall, 702 patients met the inclusion criteria. Primary colon cancer was right-sided in 248 (35.3%) patients, left-sided in 296 (42.2%) and rectal in 158 (22.5%) patients. Whatever PTL monochemotherapy give poor progression-free survival (PFS) and overall survival (OS). Triplet give better PFS and OS only for rectal cancer. When looking at doublet in first line. Folinic acid, 5FU, and irinotecan (FOLFIRI) give better PFS in rectal cancer [PFS of 21.2 (95% CI: 14.9-NR) versus 12.2 (95% CI: 10.1-13.4) months for the folinic acid, 5FU, and oxaliplatin (FOLFOX) group, P=0.009] and at trend for better PFS in right side tumor [14.9 (95% CI: 8.8-20.8) versus 11.3 (95% CI: 8.4-13.2) months for the FOLFOX group. P=0.0755]. No difference was observed in term of OS.

Conclusions

our results support that either FOLFIRI or FOLFOX regimens give similar efficacy in both left and right metastatic colic cancer. FOLFIRI and FOLFIRINOX regimens might be preferred for metastatic rectal carcinoma.

BMAL1 Knockdown Leans Epithelial-Mesenchymal Balance toward Epithelial Properties and Decreases the Chemoresistance of Colon Carcinoma Cells

The circadian clock coordinates biological and physiological functions to day/night cycles. The perturbation of the circadian clock increases cancer risk and affects cancer progression. Here, we studied how BMAL1 knockdown (BMAL1-KD) by shRNA affects the epithelial-mesenchymal transition (EMT), a critical early event in the invasion and metastasis of colorectal carcinoma (CRC). In corresponding to a gene set enrichment analysis, which showed a significant enrichment of EMT and invasive signatures in BMAL1_high CRC patients as compared to BMAL1_low CRC patients, our results revealed that BMAL1 is implicated in keeping the epithelial-mesenchymal equilibrium of CRC cells and influences their capacity of adhesion, migration, invasion, and chemoresistance. Firstly, BMAL1-KD increased the expression of epithelial markers (E-cadherin, CK-20, and EpCAM) but decreased the expression of Twist and mesenchymal markers (N-cadherin and vimentin) in CRC cell lines. Finally, the molecular alterations after BMAL1-KD promoted mesenchymal-to-epithelial transition-like changes mostly appeared in two primary CRC cell lines (i.e., HCT116 and SW480) compared to the metastatic cell line SW620. As a consequence, migration/invasion and drug resistance capacities decreased in HCT116 and SW480 BMAL1-KD cells. Together, BMAL1-KD alerts the delicate equilibrium between epithelial and mesenchymal properties of CRC cell lines, which revealed the crucial role of BMAL1 in EMT-related CRC metastasis and chemoresistance.

A Prognostic Nomogram of Colon Cancer With Liver Metastasis: A Study of the US SEER Database and a Chinese Cohort

Background

Among colon cancer patients, liver metastasis is a commonly deadly phenomenon, but there are few prognostic models for these patients.

Methods

The clinicopathologic data of colon cancer with liver metastasis (CCLM) patients were downloaded from the Surveillance, Epidemiology and End Results (SEER) database. All patients were randomly divided into training and internal validation sets based on the ratio of 7:3. A prognostic nomogram was established with Cox analysis in the training set, which was validated by two independent validation sets.

Results

A total of 5,700 CCLM patients were included. Age, race, tumor size, tumor site, histological type, grade, AJCC N status, carcinoembryonic antigen (CEA), lung metastasis, bone metastasis, surgery, and chemotherapy were independently associated with the overall survival (OS) of CCLM in the training set, which were used to establish a nomogram. The AUCs of 1-, 2- and 3-year were higher than or equal to 0.700 in the training, internal validation, and external validation sets, indicating the favorable effects of our nomogram. Besides, whether in overall or subgroup analysis, the risk score calculated by this nomogram can divide CCLM patients into high-, middle- and low-risk groups, which suggested that the nomogram can significantly determine patients with different prognosis and is suitable for different patients.

Conclusion

Higher age, the race of black, larger tumor size, higher grade, histological type of mucinous adenocarcinoma and signet ring cell carcinoma, higher N stage, RCC, lung metastasis, bone metastasis, without surgery, without chemotherapy, and elevated CEA were independently associated with poor prognosis of CCLM patients. A nomogram incorporating the above variables could accurately predict the prognosis of CCLM.

PREMIUM: A French prospective multicenter observational study of factors impacting on efficacy and compliance to cetuximab treatment in first-line KRAS wild-type metastatic colorectal cancer

Background

Cetuximab improves progression-free survival (PFS) and overall survival (OS) in patients with KRAS wild type (wt) metastatic colorectal cancer (mCRC). Few data are available on factors impacting both efficacy and compliance to cetuximab treatment, which is, in combination with chemotherapy, a standard-of-care first-line treatment regimen for patients with KRAS wt mCRC.

Patients and methods

PREMIUM is a prospective, French multicenter, observational study that recruited patients with KRAS wt mCRC scheduled to receive cetuximab, with or without first-line chemotherapy, as part of routine clinical practice, between October 28, 2009 and April 5, 2012 (ClinicalTrials.gov Identifier: NCT01756625). The main endpoints were the factors impacting on efficacy and compliance to cetuximab treatment. Predefined efficacy endpoints were PFS and safety.

Results

A total of 493 patients were recruited by 94 physicians. Median follow-up was 12.9 months. Median progression-free survival was 11 months [9.6–12]. In univariate analyses, ECOG performance status (PS), smoking status, primary tumor location, number of metastatic organs, metastasis resectability, surgery, folliculitis, xerosis and paronychia maximum grade, and acne preventive treatment were statistically significant. In multivariate analysis (Hazard Ratios of multivariate stepwise Cox models), ECOG PS, surgery, xerosis and folliculitis were positive prognostics factors for longer PFS. Among all patients, 69 (14%) were non-compliant. In multivariate analysis, no variables were statistically significant. The safety profile of cetuximab was consistent with previous studies.

Conclusions

ECOG PS <2, surgical treatment performed, and maximum grade xerosis or folliculitis developed were predictive factors of cetuximab efficacy on KRAS wt mCRC patients. Unfortunately, we failed in identifying predictive factors for compliance in these patients.

Synchronous and metachronous colorectal liver metastases: impact of primary tumor location on patterns of recurrence and survival after hepatic resection

Background:

Considerable differences in terms of prognosis exist between the right-sided (RCC) and the left-sided colon cancer (LCC).

Aim of the work:

In this study, we evaluated prognostic implications of primary tumor location (PTL) among patients who underwent curative-intent hepatectomy for synchronous (SM) and metachronous (MM) colorectal liver metastases (CRLM).

Methods:

The study population included all consecutive patients affected by CRLM scheduled for first liver resection at three Italian oncological centers.

Results:

A total of 204 patients who underwent CRLM resection were included, 50% with RCC. Synchronous lesions were prevalent (n=133, 65%). Median OS was respectively 40.3 months for SM-RCC, 53.5 months for SM-LCC, 64.5 months for MM-RCC and 81.6 months for MM-LCC. Patients with MM-LCC showed an OS better than patients with SM-RCC (p=0.008) and SM-LCC (p=0.002). PTL had no influence on RFS. RCC group had less recurrences (75% vs 86.5%), though further surgery with curative-intent was possible more in LCC group (29.3% vs 32.5%). Cox proportional hazards model analysis showed that age and the presence of SM vs MM was associated with a significantly higher hazard ratio (HR) for death (HR=1.024; 95%CI=1.005-1.043; p=0.011 and HR=2.010; 95%CI=1.328-3.043; p=0.001, respectively).

Conclusions:

We confirmed that patients with CRLM and right-sided primary colon cancer experience worse survival after hepatic resection. The timing of metastasis has been revealed as important prognostic factor.

Effect of KRAS and NRAS mutations on the prognosis of patients with synchronous metastatic colorectal cancer presenting with liver-only and lung-only metastases

It has been reported that 20-25% of patients with colorectal cancer (CRC) have metastases at the time of diagnosis. Liver and lung are the most common metastatic sites. The aim of the present study was to investigate the association of KRAS and NRAS mutations with clinicopathological features and prognosis of patients with initial liver-metastasis only (LiM-only) or lung-metastasis only (LuM-only) metastatic CRC (mCRC). Overall, 166 patients with CRC with initial LiM-only (n=124) and LuM-only (n=42) were retrospectively analyzed from January 2014 to December 2017. The median follow-up time was 19.2 months (1.0-57.1 months). Patient characteristics at diagnosis were collected. Genomic DNA was isolated from frozen primary CRC tissues for targeting KRAS and NRAS. Patients with LuM-only were significantly older compared with those with LiM-only (65.5 vs. 61.5 years; P=0.05). There was no significant differences between the LiM-only and LuM-only groups in terms of sex, location of the primary tumor, serum carcinoembryonic antigen level, histological grade and RAS mutation status. KRAS mutations were detected in 43 (41.0%) patients with LiM-only and 13 (35.1%) patients with LuM-only. The overall survival time (OS) of LuM-only was more favorable compared with that of patients with LiM-only (44.5 vs. 24.7 months); however, there was no significant difference (P=0.095). The progression-free survival (PFS) and OS in the RAS wild-type group were significantly improved compared with the RAS mutant cohorts (P=0.004 and P=0.031, respectively) in the LiM-only group. In patients with stage IV CRC, those with synchronous LiM-only mCRC had a higher incidence of metastasis but a less favorable PFS and OS compared with patients with LuM-only. RAS mutation status exhibited a significant association with the survival outcome in patients with LiM-only mCRC.

Elective surgery for tumours of the splenic flexure: a French inter-group (AFC, SFCD, FRENCH, GRECCAR) survey

BACKGROUND

In an elective setting, there is no consensus regarding the type of colectomy that is best for patients with tumors of the splenic flexure: segmental left colectomy (or splenic flexure colectomy), left hemicolectomy or subtotal colectomy (or extended right hemicolectomy). In the United Kingdom, extended right hemicolectomy is preferred by surgeons. The aim of the present survey was to report on the practices in France for this particular tumor location.

METHODS

Between 15/07/17 and 15/10/17, members of two French surgical societies [the French Association of Surgery (AFC) and the French Society of Digestive Surgery (SFCD)] and two French surgical cooperative groups [the French Federation of Surgical Research (FRENCH) and the French Research Group of Rectal Cancer Surgery (GRECCAR)] were solicited by email to answer an online anonymous questionnaire.

RESULTS

A total of 190 out of 420 surgeons participated in this study (response rate 45%). The preferred procedure was splenic flexure colectomy (70%), followed by left hemicolectomy (17%) and subtotal colectomy (13%). The most used surgical approach was laparoscopy (63%), followed by laparotomy (31%) and hand-assisted laparoscopy (6%). Lymph node dissection was extended to the middle colic artery in 29% of splenic flexure colectomies and in 33% of left hemicolectomies. Twenty-nine percent of responders thought that tumors of the splenic flexure had a worse prognosis in comparison with other colonic sites, because of insufficient lymph node dissection (73%) or a more advanced stage (50%) at diagnosis. However, this opinion did not change the type of colectomy performed.

CONCLUSIONS

There is a strong consensus in France to operate tumors of the splenic flexure with a splenic flexure colectomy and lymph node dissection limited to the left colic artery.

Impact of primary tumor location on patterns of recurrence and survival of patients undergoing resection of liver metastases from colon cancer

BACKGROUND

Several studies have described a worse prognosis for right-sided colon cancer compared to left-sided. The aim of this study was to compare patterns of recurrence and survival following resection of liver metastases (LM) from right-sided (RS) versus left-sided (LS) colon cancer.

METHODS

Patients undergoing resection for colon cancer LM between 2000 and 2017 were analyzed. Rectal cancer, multiple primaries and unknown location were excluded.

RESULTS

Out of 995 patients, 686 fulfilled inclusion criteria (RS-LM = 322, LS-LM = 364). RS colon cancer had higher prevalence of metastatic lymph nodes (67.4% vs. 57.1%, P = 0.008). RS-LM were more often mucinous (16.8% vs. 8.5%, P = 0.001) and G3 (58.3% vs. 48.9%, P = 0.014). 451 (65.7%) patients experienced recurrence (RS-LM 68.9% vs. LS-LM 62.9%). In RS-LM group, recurrence was more often encephalic (2.3% vs. 0%, P = 0.029) and at multiple sites (34.2% vs. 23.5%, P = 0.012). The rate of re-resection was lower in RS-LM patients (27.9% vs. 37.5%, P = 0.024). Multivariate analysis showed RS-LM to have worse 5-year overall (35.8% vs. 51.2%, P = 0.002) and disease-free survival (26% vs. 43.6%, P = 0.002).

CONCLUSIONS

RS-LM is associated with worse survival and aggressive recurrences, with lower chance of re-resection.

Prognostic factors and patterns of recurrence after emergency management for obstructing colon cancer: multivariate analysis from a series of 2120 patients

PURPOSE

At equal TNM stage, obstructing colon cancer (OCC) is associated with worse prognosis in comparison with uncomplicated cancer. Our aim was to identify prognostic factors of overall (OS) and disease-free survival (DFS) in patients treated for OCC.

METHODS

From 2000 to 2015, 2325 patients were treated for OCC in French surgical centers, members of the French National Surgical Association (AFC). Patients with palliative management were excluded. The main endpoints were OS and DFS. A multivariate analysis, using Cox proportional hazards regression model, was performed to determine independent prognostic factors.

RESULTS

The cohort included 2120 patients. The median of follow-up was 13.2 months. In multivariate analysis, age > 75 years, ASA score ≥ 3, ECOG score ≥ 3, right-sided colon cancer, presence of synchronous metastases, anastomotic leakage, and absence of adjuvant chemotherapy were independent OS factors. Age > 75 years, ASA score ≥ 3, right-sided colon cancer, presence of synchronous metastases, and absence of postoperative chemotherapy were independent factors of poor OS after exclusion of patients who died postoperatively. Age ≥ 75 years, ASA score ≥ 3, ECOG score ≥ 3, right-sided colon cancer, lymph node involvement, presence of vascular, lymphatic or perineural invasion, less than 12 harvested lymph nodes, and absence of adjuvant chemotherapy were independent DFS factors.

CONCLUSIONS

Management of OCC should take into account prognostic factors related to the patient (age, comorbidities), tumor location, and tumor stage. Adjuvant chemotherapy administration plays an important role. For patients undergoing initial defunctionning stoma, neoadjuvant chemotherapy could be an option to improve prognosis.

Clinical Significance of Serum Glutamine Level in Patients with Colorectal Cancer

Limited studies have assessed the associations of pretreatment serum glutamine level with clinicopathological characteristics and prognosis of colorectal cancer (CRC) patients. This study focuses on clarifying the clinical significance of baseline serum glutamine level in CRC patients. We retrospectively examine 123 patients with newly diagnosed CRC between 2009 and 2011. The associations of pretreatment serum glutamine level with clinicopathological characteristics, proinflammatory cytokines, overall survival (OS), and progression-free survival (PFS) were analyzed. We executed univariate and multivariate analyses to assess the associations between serum glutamine level and clinicopathological variables able to predict survival. Low glutamine levels were associated with older age, advanced stage, decreased albumin levels, elevated carcinoembryonic antigen levels, higher C-reactive protein levels, higher modified Glasgow prognostic scores, and higher proinflammatory cytokine levels. Furthermore, patients with low glutamine levels had poorer OS and PFS than those with high glutamine levels (p < 0.001 for both). In multivariate analysis, pretreatment glutamine level independently predicted OS (p = 0.016) and PFS (p = 0.037) in CRC patients. Pretreatment serum glutamine level constitutes an independent prognostic marker to predict survival and progression in CRC patients.

Survival nomograms for stage III colorectal cancer

The postoperative survival of patients with stage III colorectal cancer (CRC) various obviously. We sought to develop novel nomograms for predicting the survival of these patients after radical surgery and postoperative chemotherapy.A total of 620 consecutive patients with stage III CRC who underwent curative resection and postoperative chemotherapy between January 2009 and December 2015 were retrospectively collected and randomly allocated to the training (n = 372) or validation cohort (n = 248). Clinicopathological factors were collected and analyzed. On the basis of data from 372 patients in the training set, predictive factors for overall survival (OS) and disease-free survival (DFS) were identified using multivariate Cox regression and used to construct nomograms. The predictive performance of the nomograms was assessed by concordance index (C-index) and calibration plots. An external cohort of 248 patients was used to validate the nomograms. Furthermore, nomogram performance was compared with the performance of T and N stage stratification.Tumor differentiation grade, lymph node metastasis ratio, intravascular emboli (IVE), preoperative serum carcinoembryonic antigen (CEA) level, albumin to globulin ratio (AGR), T stage and N stage were significant prognostic factors for OS on multivariate analysis; whereas, Tumor differentiation grade, lymph node metastasis ratio, IVE, AGR and N stage were significant for DFS. Nomograms to predict 3- and 5-year OS and DFS were established that performed well (C-indexes of 0.734 [95% CI, 0.691-0.779] for OS and 0.699 [95% CI, 0.657-0.740] for DFS prediction), and nomogram accuracy was confirmed in the validation cohort. Furthermore, model comparison proved that the nomograms were superior to risk stratification by T and N stage for stage III CRC.We propose 2 practical nomograms for stage III CRC patients that provide more accurate prognostic predictions and should be helpful for guiding individualized treatment and postoperative surveillance.

Colorectal Cancer: Why Does Side Matter?

Colorectal cancer (CRC) is a heterogeneous disease, and the search for clinical and molecular prognostic and predictive factors is thus necessary to better tailor each individual patient's management. Primary tumor location (PTL) seems to act as a master prognostic factor pooling different clinical, pathological, and molecular poor prognostic factors. In fact, right-sided (RS) CRC patients are more frequently female and elderly with microsatellite unstable, BRAF mutated, CpG island methylator phenotype (CIMP)-high, poorly differentiated tumors, compared to left-sided (LS) CRC patients. PTL does not seem to clearly influence disease-free survival (DFS) in localised colon cancer even though the opposite prognostic value of RS tumors on DFS depending on RAS/BRAF mutational status has been recently suggested in these patients. In metastatic CRC (mCRC), the poor prognosis associated with RS tumors is confirmed in the most recent publications in the era of double and triple chemotherapeutic regimens and targeted agents. Concerning the predictive value of PTL, in patients with RAS wild-type mCRC in the first-line setting, anti-epidermal growth factor receptor (EGFR) therapy combined with chemotherapy appears to be more effective than bevacizumab in LS CRC, while patients with RS CRC benefit less from anti-EGFR therapy, and intensive chemotherapy plus bevacizumab may be more appropriate but EGFR antibodies remain an option if objective response is needed. Due to the limitation of the current data (unplanned and retrospective analyses), these conclusions must be interpreted with caution. Clinical trials in RS CRC may be of interest to clarify what is the best treatment strategy in these patients.

Report from the 19th annual Western Canadian Gastrointestinal Cancer Consensus Conference; Winnipeg, Manitoba; 29-30 September 2017

The 19th annual Western Canadian Gastrointestinal Cancer Consensus Conference (wcgccc) was held in Winnipeg, Manitoba, 29-30 September 2017. The wcgccc is an interactive multidisciplinary conference attended by health care professionals from across Western Canada (British Columbia, Alberta, Saskatchewan, and Manitoba) who are involved in the care of patients with gastrointestinal cancer. Surgical, medical, and radiation oncologists; pathologists; radiologists; and allied health care professionals participated in presentation and discussion sessions for the purpose of developing the recommendations presented here. This consensus statement addresses current issues in the management of colorectal cancer.

Right- and left-sided stage III colon cancers present different prognostic outcomes of oxaliplatin-based adjuvant chemotherapy after curative resection

Background

Growing evidence has suggested that right-sided colon cancer (RCC) and left-sided colon cancer (LCC) should be considered as different tumor entities. However, stage III colon cancer is currently treated as the same entity with uniform therapy. This study was aimed at investigating the prognostic influence of tumor location in patients with stage III colon cancer receiving adjuvant chemotherapy after curative resection.

Patients and methods

We retrospectively analyzed 274 eligible patients with stage III colon cancer undergoing curative tumor resection followed by adjuvant chemotherapy with oxaliplatin and capecitabine between December 2007 and December 2013. Disease-free survival (DFS) and overall survival (OS) were analyzed using Kaplan–Meier and log-rank tests, and prognostic factors were identified by Cox regression methods.

Results

Patients with RCC exhibited lower hemoglobin levels (23.6% vs. 9.8%; P = 0.002), larger tumor size (60.6% vs. 40.9%; P = 0.001), and a higher proportion of 12 or more resected lymph nodes (86.4% vs. 64.6%; P < 0.001) than patients with LCC. Grade 1 neurotoxicity was more common in patients with RCC than in those with LCC (53.6% vs. 40.9%; P = 0.037). RCC was significantly associated with a shorter 3-year OS than LCC, whereas a difference was noted only for stage IIIC and not stage IIIA or stage IIIB colon cancer. Multivariate analyses revealed that RCC was independently associated with a worse 3-year OS (hazard ratio: 2.213; 95% CI: 1.063–4.606; P = 0.002). In addition, an increase in 3-year OS and DFS after 6–8 cycles of adjuvant chemotherapy was only observed in patients with RCC and not in those with LCC.

Conclusion

This study indicated that RCC has a worse prognostic outcome for stage III colon cancer, and a full course of adjuvant chemotherapy should be suggested for patients with RCC.

Primary Tumor Location in Colorectal Cancer: Comparison of Right- and Left-Sided Colorectal Cancer Characteristics for the Interventional Radiologist

One area which has emerged as an important factor for predicting molecular profile and treatment outcomes in metastatic colorectal cancer (mCRC) is primary tumor location. The importance of molecular characteristics of colorectal cancer has been firmly established in terms of prognosis and treatment algorithms for many years. Recent studies have also suggested that molecular profiles are important in locoregional therapies as well, with some data suggesting changes in treatment algorithms based on tumor location. Therefore, it is important for interventional radiologists to understand the basic molecular characteristics and development pathways of mCRC. Here, these disease characteristics are reviewed and the differences in left- versus right-sided primary tumor location are explored.

Identifying miRNA and gene modules of colon cancer associated with pathological stage by weighted gene co-expression network analysis

Introduction

Colorectal cancer (CRC) is the fourth most common cause of cancer-related mortality worldwide. The tumor, node, metastasis (TNM) stage remains the standard for CRC prognostication. Identification of meaningful microRNA (miRNA) and gene modules or representative biomarkers related to the pathological stage of colon cancer helps to predict prognosis and reveal the mechanisms behind cancer progression.

Materials and methods

We applied a systems biology approach by combining differential expression analysis and weighted gene co-expression network analysis (WGCNA) to detect the pathological stage-related miRNA and gene modules and construct a miRNA–gene network. The Cancer Genome Atlas (TCGA) colon adenocarcinoma (CAC) RNA-sequencing data and miRNA-sequencing data were subjected to WGCNA analysis, and the GSE29623, GSE35602 and GSE39396 were utilized to validate and characterize the results of WGCNA.

Results

Two gene modules (Gmagenta and Ggreen) and one miRNA module were associated with the pathological stage. Six hub genes (COL1A2, THBS2, BGN, COL1A1, TAGLN and DACT3) were related to prognosis and validated to be associated with the pathological stage. Five hub miRNAs were identified to be related to prognosis (hsa-miR-125b-5p, hsa-miR-145-5p, hsa-let-7c-5p, hsa-miR-218-5p and hsa-miR-125b-2-3p). A total of 18 hub genes and seven hub miRNAs were predominantly expressed in tumor stroma. Proteoglycans in cancer, focal adhesion, extracellular matrix (ECM)–receptor interaction and so on were common pathways of the three modules. Hsa-let-7c-5p was located at the core of miRNA–gene network.

Conclusion

These findings help to advance the understanding of tumor stroma in the progression of CAC and provide prognostic biomarkers as well as therapeutic targets.

Knockdown of Beclin-1 impairs epithelial-mesenchymal transition of colon cancer cells

Activation of autophagy significantly affects cancer cell behaviors, such as proliferation, differentiation, and invasiveness. Epithelial-to-mesenchymal transition (EMT) as an initial step of malignant transformation of cancer cells was linked to the activation of autophagy, but the detailed molecular mechanisms are still unknown. The present study investigates the effects of Beclin-1, a key molecule involved in activation of autophagy, on EMT of colon cancer cells. The normal colon epithelia cell line of CCD-18Co and six colon cancer cell lines with different expression levels of Beclin-1 were used in this study. The activation of autophagy and EMT markers of cancer cells were monitored by Western blotting and quantitative real-time PCR assay in the presence or absence of rapamycin (autophagy activator) and 3-MA (autophagy inhibitor). The expression of Beclin-1 in selected cell lines was modulated using small interfering RNA, and consequentially EMT markers, and cancer cell behaviors including migration and invasion, were also explored. Activation or inhibition of autophagy in colon cancer cells had positive or negative impacts on the expression of EMT markers and malignant behaviors such as cell migration and invasion. Knockdown of beclin-1 by siRNA apparently inhibited the activation of autophagy induced by rapamycin, consequentially resulted in suppression of EMT and attenuation of invasiveness of colon cancer cells. The results in this study demonstrated an association between activation of autophagy and EMT in colon cancer cells. The results showed suppression of Beclin-1 expression significantly reduced EMT and invasive behaviors in colon cancer cells.

Prognostic and predictive value of primary tumour side in patients with RAS wild-type metastatic colorectal cancer treated with chemotherapy and EGFR directed antibodies in six randomized trials

Background

There is increasing evidence that metastatic colorectal cancer (mCRC) is a genetically heterogeneous disease and that tumours arising from different sides of the colon (left versus right) have different clinical outcomes. Furthermore, previous analyses comparing the activity of different classes of targeted agents in patients with KRAS wild-type (wt) or RAS wt mCRC suggest that primary tumour location (side), might be both prognostic and predictive for clinical outcome.

Methods

This retrospective analysis investigated the prognostic and predictive influence of the localization of the primary tumour in patients with unresectable RAS wt mCRC included in six randomized trials (CRYSTAL, FIRE-3, CALGB 80405, PRIME, PEAK and 20050181), comparing chemotherapy plus EGFR antibody therapy (experimental arm) with chemotherapy or chemotherapy and bevacizumab (control arms). Hazard ratios (HRs) and 95% confidence intervals (CIs) for overall survival (OS) and progression-free survival (PFS) for patients with left-sided versus right-sided tumours, and odds ratios (ORs) for objective response rate (ORR) were estimated by pooling individual study HRs/ORs. The predictive value was evaluated by pooling study interaction between treatment effect and tumour side.

Results

Primary tumour location and RAS mutation status were available for 2159 of the 5760 patients (37.5%) randomized across the 6 trials, 515 right-sided and 1644 left-sided. A significantly worse prognosis was observed for patients with right-sided tumours compared with those with left-sided tumours in both the pooled control and experimental arms for OS [HRs = 2.03 (95% CI: 1.69-2.42) and 1.38 (1.17-1.63), respectively], PFS [HRs = 1.59 (1.34-1.88) and 1.25 (1.06-1.47)], and ORR [ORs = 0.38 (0.28-0.50) and 0.56 (0.43-0.73)]. In terms of a predictive effect, a significant benefit for chemotherapy plus EGFR antibody therapy was observed in patients with left-sided tumours [HRs = 0.75 (0.67-0.84) and 0.78 (0.70-0.87) for OS and PFS, respectively] compared with no significant benefit for those with right-sided tumours [HRs = 1.12 (0.87-1.45) and 1.12 (0.87-1.44) for OS and PFS, respectively; P value for interaction <0.001 and 0.002, respectively]. For ORR, there was a trend (P value for interaction = 0.07) towards a greater benefit for chemotherapy plus EGFR antibody therapy in the patients with left-sided tumours [OR = 2.12 (1.77-2.55)] compared with those with right-sided tumours [OR = 1.47 (0.94-2.29)]. Exclusion of the unique phase II trial or the unique second-line trial had no impact on the results. The predictive effect on PFS may depend of the type of EGFR antibody therapy and on the presence or absence of bevacizumab in the control arm.

Conclusion

This pooled analysis showed a worse prognosis for OS, PFS and ORR for patients with right-sided tumours compared with those with left-sided tumours in patients with RAS wt mCRC and a predictive effect of tumour side, with a greater effect of chemotherapy plus EGFR antibody therapy compared with chemotherapy or chemotherapy and bevacizumab, the effect being greatest in patients with left-sided tumours. These predictive results should be interpreted with caution due to the retrospective nature of the analysis, which was carried out on subpopulations of patients included in these trials, and because none of these studies contemplated a full treatment sequence strategy.

Clinical importance of DNA repair in sporadic colorectal cancer

Colorectal cancer (CRC) is the third major cause of cancer-related deaths worldwide. However, despite the scientific efforts to provide a molecular classification to improve CRC clinical practice management, prognosis and therapeutic decision are still strongly dependent on the TNM staging system. Mismatch repair system deficiencies can occur in many organs, but it is mainly a hallmark of CRC influencing clinical outcomes and response to therapy. This review will discuss the effect of the modulation of other DNA repair pathways (direct, excision and double strand break repairs) in the clinical and pathological aspects of colorectal cancer and its potential as prognostic and predictive biomarkers.

Does the Site of the Primary Affect Outcomes When Ablating Colorectal Liver Metastases with Radiofrequency Ablation?

PURPOSE

To determine whether primary tumor side was a predictor of radiofrequency ablation (RFA) outcome in colorectal liver metastases (CRLM).

MATERIALS AND METHODS

The institutional review board approved this retrospective study. Written informed consent was obtained from all patients. From January 2007 to December 2013, 102 patients underwent RFA of metachronous CRLM were enrolled in this study with propensity score matching method. Recurrence rate (RR) and overall survival (OS) were analyzed between two patients cohorts with primary left-side colorectal cancer (LSCRC) or primary right-side colon cancer (RSCC).

RESULTS

The total RR was 59.8% in all patients. Patients in LSCRC cohort had lower RR and non-local recurrence (NLR) rate than those in RSCC patients' cohort (49.0 vs 70.6%, p = 0.026 and 21.6 vs 41.2%, p = 0.033). Five-year OS was 14 and 30% for RSCC and LSCRC, respectively. There was a significant difference between two cohorts in median OS (29.4 vs 40.3 months for RSCC and LSCRC, respectively, p = 0.042). Univariate analysis showed that primary tumor side, the number of liver metastases, tumor size, carcinoembryonic antigen level, differentiation, TNM stage, active chemotherapy and RFA boundary were significant in predicting OS. When these variables were subsequently entered in a multivariate model, RSCC (p < 0.001; hazard ratio [HR], 6.2) and tumor size (> 3 cm) (p = 0.006; HR, 3.9) were significant.

CONCLUSION

LSCRC and tumor size (≤ 3 cm) are independent predictors of RFA in CRLM and yield the better oncologic outcomes.

Prognostic value of preoperative prognostic nutritional index and its associations with systemic inflammatory response markers in patients with stage III colon cancer

Background

The prognostic nutritional index (PNI) has been widely applied for predicting survival outcomes of patients with various malignant tumors. Although a low PNI predicts poor prognosis in patients with colorectal cancer after tumor resection, the prognostic value remains unknown in patients with stage III colon cancer undergoing curative tumor resection followed by adjuvant chemotherapy. This study aimed to investigate the prognostic value of PNI in patients with stage III colon cancer.

Methods

Medical records of 274 consecutive patients with stage III colon cancer undergoing curative tumor resection followed by adjuvant chemotherapy with oxaliplatin and capecitabine between December 2007 and December 2013 were reviewed. The optimal PNI cutoff value was determined using receiver operating characteristic (ROC) curve analysis. The associations of PNI with systemic inflammatory response markers, including lymphocyte-to-monocyte ratio (LMR), neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), and C-reactive protein (CRP) level, and clinicopathologic characteristics were assessed using the Chi square or Fisher’s exact test. Correlation analysis was performed using Spearman’s correlation coefficient. Disease-free survival (DFS) and overall survival (OS) stratified by PNI were analyzed using Kaplan–Meier method and log-rank test, and prognostic factors were identified by Cox regression analyses.

Results

The preoperative PNI was positively correlated with LMR (r = 0.483, P < 0.001) and negatively correlated with NLR (r = − 0.441, P < 0.001), PLR (r = − 0.607, P < 0.001), and CRP level (r = − 0.333, P < 0.001). A low PNI (≤ 49.22) was significantly associated with short OS and DFS in patients with stage IIIC colon cancer but not in patients with stage IIIA/IIIB colon cancer. In addition, patients with a low PNI achieved a longer OS and DFS after being treated with 6–8 cycles of adjuvant chemotherapy than did those with < 6 cycles. Multivariate analyses revealed that PNI was independently associated with DFS (hazard ratios 2.001; 95% confidence interval 1.157–3.462; P = 0.013).

Conclusion

The present study identified preoperative PNI as a valuable predictor for survival outcomes in patients with stage III colon cancer receiving curative tumor resection followed by adjuvant chemotherapy.

ZEB1 Promotes Oxaliplatin Resistance through the Induction of Epithelial - Mesenchymal Transition in Colon Cancer Cells

Background: Oxaliplatin (OXA) chemotherapy is widely used in the clinical treatment of colon cancer. However, chemo-resistance is still a barrier to effective chemotherapy in cases of colon cancer. Accumulated evidence suggests that the epithelial mesenchymal transition (EMT) may be a critical factor in chemo-sensitivity. The present study investigated the effects of Zinc finger E-box binding homeobox 1 (ZEB1) on OXA-sensitivity in colon cancer cells.

Method: ZEB1expression and its correlation with clinicopathological characteristics were analyzed using tumor tissue from an independent cohort consisting of 118 colon cancer (CC) patients who receiving OXA-based chemotherapy. ZEB1 modulation of OXA-sensitivity in colon cancer cells was investigated in a OXA-resistant subline of HCT116/OXA cells and the parental colon cancer cell line: HCT116. A CCK8 assay was carried out to determine OXA-sensitivity. qRT-PCR, Western blot, Scratch wound healing and transwell assays were used to determine EMT phenotype of colon cells. ZEB1 knockdown using small interfering RNA (siRNA) was used to determine the ZEB1 contribution to OXA-sensitivity in vitro and in vivo (in a nude mice xenograft model).

Result: ZEB1 expression was significantly increased in colon tumor tissue, and was correlated with lymph node metastasis and the depth of invasion. Compared with the parental colon cancer cells (HCT116), HCT116/OXA cells exhibited an EMT phenotype characterized by up-regulated expression of ZEB1, Vimentin, MMP2 and MMP9, but down-regulated expression of E-cadherin. Transfection of Si-ZEB1 into HCT116/OXA cells significantly reversed the EMT phenotype and enhanced OXA-sensitivity in vitro and in vivo.

Conclusion: HCT116/OXA cells acquired an EMT phenotype. ZEB1 knockdown effectively restored OXA-sensitivity by reversing EMT. ZEB1 is a potential therapeutic target for the prevention of OXA-resistance in colon cancer.

Excision Repair Cross-complementation Group 1 is a Prognostic Biomarker in Patients with Colorectal Cancer Receiving Chemotherapy

Background:

Conflicting results about the association between expression level of excision repair cross-complementation group 1 (ERCC1) and clinical outcome in patients with colorectal cancer (CRC) receiving chemotherapy have been reported. Thus, we searched the available articles and performed the meta-analysis to elucidate the prognostic role of ERCC1 expression in patients with CRC.

Methods:

A thorough literature search using PubMed (Medline), Embase, Cochrane Library, Web of Science databases, and Chinese Science Citation Database was conducted to obtain the relevant studies. Pooled hazard ratios (HRs) or odds ratios (ORs) with 95% confidence intervals (CIs) were calculated to estimate the results.

Results:

A total of 11 studies were finally enrolled in this meta-analysis. Compared with patients with lower ERCC1 expression, patients with higher ERCC1 expression tended to have unfavorable overall survival (OS) (HR = 2.325, 95% CI: 1.720–3.143, P < 0.001), progression-free survival (PFS) (HR = 1.917, 95% CI: 1.366–2.691, P < 0.001) and poor response to chemotherapy (OR = 0.491, 95% CI: 0.243–0.990, P = 0.047). Subgroup analyses by treatment setting, ethnicity, HR extraction, detection methods, survival analysis, and study design demonstrated that our results were robust.

Conclusions:

ERCC1 expression may be taken as an effective prognostic factor predicting the response to chemotherapy, OS, and PFS. Further studies with better study design and longer follow-up are warranted in order to gain a deeper understanding of ERCC1's prognostic value.

Prognostic and Predictive Relevance of Primary Tumor Location in Patients With RAS Wild-Type Metastatic Colorectal Cancer: Retrospective Analyses of the CRYSTAL and FIRE-3 Trials

IMPORTANCE

Metastatic colorectal cancer (mCRC) is heterogeneous, and primary tumors arising from different regions of the colon are clinically and molecularly distinct.

OBJECTIVE

To examine the prognostic and predictive value of primary tumor location in patients with RAS wild-type (wt) mCRC treated with first-line fluorouracil, leucovorin, and irinotecan (FOLFIRI) plus cetuximab in the Cetuximab Combined With Irinotecan in First-line Therapy for Metastatic Colorectal Cancer (CRYSTAL) trial and FOLFIRI Plus Cetuximab Versus FOLFIRI Plus Bevacizumab as First-Line Treatment For Patients With Metastatic Colorectal Cancer (FIRE-3) trial.

DESIGN, SETTING, AND PARTICIPANTS

In this retrospective analysis patients with RAS wt metastatic colorectal cancer from the CRYSTAL and FIRE-3 trials were classified as having left-sided or right-sided mCRC, defined, respectively, as patients whose tumors originated in the splenic flexure, descending colon, sigmoid colon, or rectum vs appendix, cecum, ascending colon, hepatic flexure, or transverse colon.

MAIN OUTCOMES AND MEASURES

Progression-free survival (PFS), overall survival (OS), and objective response rate (ORR) were assessed according to tumor location and treatment arm.

RESULTS

In the RAS wt populations of the CRYSTAL and FIRE-3 trials, patients with left-sided tumors (n = 142 and n = 157, respectively) had markedly superior PFS, OS, and ORR compared with patients with right-sided tumors (n = 33 and n = 38, respectively). Among CRYSTAL and FIRE-3 study patients with RAS wt left-sided tumors, FOLFIRI plus cetuximab significantly improved OS relative to the respective comparators (FOLFIRI and FOLFIRI plus bevacizumab); in contrast, in RAS wt patients with poor-prognosis right-sided tumors, limited efficacy benefits were observed upon the addition of cetuximab to FOLFIRI in CRYSTAL, and comparable outcomes were observed between the FOLFIRI plus cetuximab and FOLFIRI plus bevacizumab arms of FIRE-3. A significant interaction was observed between primary tumor location and treatment for OS (CRYSTAL: hazard ratio [HR], 1.95; 95% CI, 1.09-3.48 and FIRE-3: HR, 0.40; 95% CI, 0.23-0.70) within the RAS wt populations of both studies in multivariable models that also included sex, prior adjuvant therapy, and BRAF mutational status.

CONCLUSIONS AND RELEVANCE

In the RAS wt populations of CRYSTAL and FIRE-3, patients with left-sided tumors had a markedly better prognosis than those with right-sided tumors. First-line FOLFIRI plus cetuximab clearly benefitted patients with left-sided tumors (vs FOLFIRI or FOLFIRI plus bevacizumab, respectively), whereas patients with right-sided tumors derived limited benefit from standard treatments.

TRIAL REGISTRATION

clinicaltrials.gov Identifiers: CRYSTAL, NCT00154102, and FIRE-3, NCT00433927.

The relevance of primary tumour location in patients with metastatic colorectal cancer: A meta-analysis of first-line clinical trials

BACKGROUND

Retrospective subgroup analyses suggest that primary tumour location (PTL) has a prognostic importance and relates to response to targeted therapy.

METHODS

We conducted a meta-analysis of first-line clinical trials available up to October 2016, which assessed the relevance of PTL in patients with metastatic colorectal cancer (mCRC). Right- and left-sided colorectal cancers were differentiated (RC and LC).

RESULTS

In 13 first-line randomised controlled trials and one prospective pharmacogenetic study, RC was associated with a significantly worse prognosis compared with LC (hazard ratio [HR] for overall survival: 1.56; 95% confidence interval [CI]: 1.43-1.70; P < 0.0001). A meta-analysis of PRIME and CRYSTAL study suggests that PTL was predictive of survival benefit from addition of anti-EGFR antibody to standard chemotherapy in patients with RAS wild-type tumour (overall survival, HR for LC: 0.69; 95% CI: 0.58-0.83; P < 0.0001 and HR for RC: 0.96; 95% CI: 0.68-1.35; P = 0.802). A meta-analysis of FIRE-3/AIO KRK0306, CALGB/SWOG 80405 and PEAK study indicates that patients with RAS wild-type LC had a significantly greater survival benefit from anti-EGFR treatment compared with anti-VEGF treatment when added to standard chemotherapy (HR 0.71; 95% CI: 0.58-0.85; P = 0.0003). By contrast, in patients with RC, benefit from standard therapy was poor and bevacizumab-based treatment was numerically associated with longer survival (HR 1.3; 95% CI: 0.97-1.74; P = 0.081).

CONCLUSIONS

The present meta-analysis demonstrates that PTL is prognostic in mCRC. Further, it supports the conclusion that patients with left-sided RAS wild-type mCRC should be preferentially treated with an anti-EGFR antibody. In right-sided mCRC, chemotherapy plus bevacizumab is a treatment option, but optimal treatment has yet to be defined.

Knockdown of NDRG1 promote epithelial-mesenchymal transition of colorectal cancer via NF-κB signaling

BACKGROUND

NDRG1 plays important roles in tumor growth and metastasis of colorectal cancer (CRC). The relation between NDRG1 and metastatic colorectal cancer (mCRC) has not been identified and the mechanism of NDRG1 involving in mCRC needs to be elucidated.

METHODS

Correlations between NDRG1 and clinicopathological characteristics and prognosis of 164 patients with mCRC were evaluated. Sensitivity of NDRG1-knockdown colon cancer cell to irinotecan (CPT-11) was determined by MTT assay. Blocking of NF-κB signaling by p65 siRNA interference was carried out to explore the mechanism of NDRG1 involving in epithelial-mesenchymal transition (EMT)-regulated invasion and metastasis of CRC.

RESULTS

NDRG1 expression was significantly negatively correlated with differentiation (P = 0.008) and lymph node metastasis (P = 0.016) of mCRC. NDRG1 was a favorable prognostic factor of mCRC, although might be responsible for CPT-11 resistance in vitro. Knockdown of NDRG1 promoted EMT of CRC cells via NF-κB signaling. Depletion of NDRG1 increased phosphorylation level of NF-κB. E-cadherin expression was increased and Vimentin expression was reduced in the p65-siRNA treated group, compared with the control group (P < 0.001).

CONCLUSIONS

NDRG1 appears to prevent EMT-induced metastasis by attenuating NF-κB signaling in mCRC. NDRG1 may be an independent prognostic factor for good survival of mCRC. J. Surg. Oncol. 2016;114:520-527. © 2016 Wiley Periodicals, Inc.

Nucleotide excision repair and response and survival to chemotherapy in colorectal cancer patients

Several new chemotherapeutic agents have become available for the treatment of colorectal cancer, which has led to increased complexity in treatment planning. Treatment decision making for individual patients could be facilitated if guided by predictive and prognostic markers. As most cytotoxic drugs induce DNA damage, the DNA damage repair pathways hold potential for yielding such biomarkers. Here, we review the current evidence of a possible involvement of the nucleotide excision repair pathway in the efficacy of chemotherapeutic agents used in the treatment of colorectal cancer. Although a large number of studies have been conducted, they are generally of moderate size and heterogeneous in design. Up to date no firm conclusions can be drawn to translate these results into the clinic. We recommend further comprehensive investigations of the nucleotide excision repair pathway in large patient studies that include both discovery and validation cohorts.

Prognostic impact of mutation profiling in patients with stage II and III colon cancer

Development of colorectal cancer (CRC) associates with accumulation of genetic mutations include the epidermal growth factor receptor (EGFR) signaling pathway. However, whether mutations in KRAS together with downstream factors BRAF, PIK3CA and NRAS impact prognosis is still unclear for stage II-III colon cancer. In the present study a total of 228 stage II-III colon cancer samples were retrospectively collected, KRAS (codons 12, 13 and 61), BRAF (exon 11 and exon 15), PIK3CA (exon 9 and exon 20) and NRAS (codons 12, 13 and 61) status was detected by Sanger sequencing, 37.89% (86/227) tumors harbored a KRAS mutation, 7.02% (16/228) harbored a BRAF mutation, 13.18% (29/220) harbored a PIK3CA mutation and 0.89% (2/224) harbored a NRAS mutation. NRAS mutations existed only in stage II colon cancer. Older groups harbored a higher KRAS and BRAF mutation (P < 0.05), PIK3CA (exon9) mutations appeared more common in worse differentiation tumors (P = 0.032). Moreover, PIK3CA (E545K) mutation was significantly associated with tumor recurrence (P = 0.031) and acted independently prognostic for poor OS (P = 0.044), while only in stage III colon cancer. KRAS, BRAF and NRAS mutations do not have major prognostic value in stage II and III colon cancer, subtypes of gene mutations should be further investigated for a better understanding in CRC.