Carcinoma obstruction of the proximal colon cancer and long-term prognosis--obstruction is a predictor of worse outcome in TNM stage II tumor

From blockage to biology: Unveiling the role of extracellular matrix dynamics in obstructive colorectal cancer pathogenesis

Colorectal cancer obstruction is a common problem with distinct symptomatic clues on CT/MR images even under incomplete conditions. The choice of management in the emergency setting has a significant effect on the prognosis of obstructive and nonobstructive colorectal cancer patients. Previous studies have demonstrated that obstruction in colorectal cancer is associated with significantly poorer outcomes, alongside distinct alterations in the composition of the extracellular matrix. Based on accumulating evidence, it is hypothesized that ECM remodeling plays a pivotal role in the development of colorectal cancer obstruction. This review explores the pathological features of obstructive colorectal cancer, emphasizing extracellular matrix remodeling as a central process. Key mechanisms include tumor-stromal cell interactions, tumor cell aggregation and migration mediated by the peripheral nervous system, vascular and lymphatic remodeling within the tumor microenvironment, and microbiota-mediated regulation of cancer progression. These findings demonstrate that further remodeling of the extracellular matrix may be a molecular biological feature of obstructive colorectal cancer with poor prognosis.

Prognostic value of carcinoembryonic antigen (CEA) and CA 19-9 levels in patients with obstructive colorectal cancer treated with a self-expandable metallic stent and curative surgery

PURPOSE

The importance of tumor markers is well established; yet little is known about their prognostic value for patients with obstructive colorectal cancer (OCRC). We investigated the clinical significance of carcinoembryonic antigen (CEA) and CA 19-9 levels in patients with non-metastatic OCRC, who underwent insertion of a self-expandable metallic stent and curative surgery.

METHODS

Clinical data on 91 patients with OCRC were analyzed retrospectively to evaluate the associations of preoperative serum values of tumor makers with short- and long-term outcomes.

RESULTS

The 91 patients comprised 53 men and 38 women, with a median age of 71 years. Twelve patients had an elevated preoperative CA 19-9 level. Multivariate analyses revealed that an elevated CA 19-9 level was independently associated with poor disease-free survival (DFS) [hazard ratio (HR) = 4.57, 95% confidence interval (CI) 2.06-10.14, P < 0.001] and overall survival (HR = 4.06, 95% CI 1.46-11.24, P = 0.007). A CEA level > 5 ng/ml had no prognostic value, whereas a CEA level > 10.8 ng/ml was significantly associated with worse DFS (P = 0.032).

CONCLUSION

Measuring the CA 19-9 level concomitantly with the CEA level for patients with advanced CRC, including OCRC, may provide a valuable means to improve prognostication.

Risk of metachronous peritoneal metastases after surgery for obstructive colon cancer: Multivariate analysis from a series of 1,085 patients

BACKGROUND

Data in the literature suggest that obstruction is an independent predictor of poor prognosis in colon cancer. Of all possible sites of recurrence, peritoneal metastases are associated with worse survival. Our aim was to report the incidence of metachronous peritoneal metastases from a cohort of patients undergoing resection of obstructive colon cancer with curative intent and to identify predictive factors for metachronous peritoneal metastases.

METHODS

From 2000 to 2015, a total of 2,325 patients were treated for obstructive colon cancer in French surgical centers, members of the French National Surgical Association (AFC). Patients with palliative management, synchronous metastatic disease, and with postoperative mortality were excluded. A multivariate analysis was performed to determine independent predictive factors of metachronous peritoneal metastases.

RESULTS

The cohort included 1,085 patients. The median follow-up was 21.5 months. Metachronous peritoneal metastases occurred in 12% of patients and were diagnosed after a median interval of 13.5 months. The cumulative 3-year metachronous peritoneal metastasis rate was 10.9%. Three-year overall survival was 85% for patients who did not develop recurrence, 71% for those who develop recurrence without peritoneal metastases, and 56% for those with metachronous peritoneal metastases (P < .0001). In multivariate analysis, 3 variables were identified as independent risk factors for metachronous peritoneal metastases: pT4 stage (odds ratio: 1.98; 95% confidence interval: 1.17-3.36; P = .011), pN2 stage (odds ratio: 2.57; 95% confidence interval: 1.89-4.45; P = .0007), and fewer than 12 lymph nodes examined (odds ratio: 2.01; 95% confidence interval: 1.08-3.74; P = .028).

CONCLUSION

This study showed a significant risk of metachronous peritoneal metastases after curative-intent resection of obstructive colon cancer. The awareness of factors predisposing to metachronous peritoneal metastases could improve the treatment strategy of these patients.

Efficacy and Safety Analysis of Emergency Endoscopic Self-Expanding Metal Stent Placement Without Fluoroscopic Assistance for Right-Sided Colonic Cancer Obstruction

BACKGROUND

Traditionally, surgical treatment is recommended for right-sided colonic cancer obstruction (RCCO); however, the literature comparing surgical or non-surgical procedures is lacking.

METHODS

Patients included in this study were divided into two groups: one group received elective surgery after self-expanding metal stent (SEMS) placement, i.e., the bridge to surgery (BTS) group, and one group received emergency surgery (ES).

RESULTS

Thirty-five patients were included in the BTS group and 60 patients underwent ES. The technical and clinical success rates for SEMS placement were 100% and 88.6%, respectively, while the short-term complication rates were 51.4% and 33.3% for the BTS and ES groups, respectively (p = 0.082). Overall, 2.9% and 3.3% of postoperative deaths occurred in the BTS and ES groups (p = 1.000). The 1-year overall survival (OS) rates were 91.4% and 88.3% (p = 0.840), 3-year OS rates were 85.7% and 81.7% (p = 0.860), and 5-year OS rates were 82.9% and 76.7% (p = 0.620) in the BTS and ES groups, respectively. No tumor recurrence was found in the BTS group but seven recurrences were found in the ES group (11.7%) [p = 0.091]. Laparoscopic surgery was chosen by 42.9% of patients in the BTS group and 26.7% of patients in the ES group (p = 0.104); however, the length of hospital stay (p = 0.001) was longer in the BTS group.

CONCLUSIONS

In the two groups, no differences were found in terms of postoperative complications and mortality as well as OS. The BTS group preferred to perform laparoscopic surgery and the technical success rate of stenting was high, therefore SEMS for RCCO was considered safe and feasible.

Postponing surgery to optimise patients with acute right-sided obstructing colon cancer - A pilot study

BACKGROUND

Right-sided obstructing colon cancer is most often treated with acute resection. Recent studies on right-sided obstructing colon cancer report higher mortality and morbidity rates than those in patients without obstruction. The aim of this study is to retrospectively analyse whether it is possible to optimise the health condition of patients with acute right-sided obstructing colon cancer, prior to surgery, and whether this improves postoperative outcomes.

METHOD

All consecutive patients with high suspicion of, or histologically proven, right-sided obstructing colon cancer, treated with curative intent between March 2013 and December 2019, were analysed retrospectively. Patients were divided into two groups: optimised group and non-optimised group. Pre-operative optimisation included additional nutrition, physiotherapy, and, if needed, bowel decompression.

RESULTS

In total, 54 patients were analysed in this study. Twenty-four patients received optimisation before elective surgery, and thirty patients received emergency surgery, without optimisation. Scheduled surgery was performed after a median of eight days (IQR 7-12). Postoperative complications were found in twelve (50%) patients in the optimised group, compared to twenty-three (77%) patients in the non-optimised group (p = 0.051). Major complications were diagnosed in three (13%) patients with optimisation, compared to ten (33%) patients without optimisation (p = 0.111). Postoperative in-hospital stay, 30-day mortality, as well as primary anastomosis were comparable in both groups.

CONCLUSION

This pilot study suggests that pre-operative optimisation of patients with obstructing right sided colonic cancer may be feasible and safe but is associated with longer in-patient stay.

Comprehensive analysis of novel cancer prediction genes and tumor microenvironment infiltration in colon cancer

BACKGROUND

Colon cancer with high incidence and mortality is a severe public health problem. As an emerging therapy, immunotherapy has played an active clinical role in tumor treatment, but only a small number of patients respond.

METHODS

By univariate Cox regression analysis of 165 novel cancer prediction genes (NCPGs), 29 NCPGs related to prognosis were screened. Based on these 29 NCPGs and 336 differentially expressed genes, we constructed two colon cancer subgroups and three gene clusters and analyzed prognosis, activation pathways, and immune infiltration characteristics under various modification patterns. Then each patient was scored and divided into high or low NCPG_score groups. A comprehensive evaluation between NCPG_score and clinical characteristics, tumor microenvironment (TME), tumor somatic mutations, and the potential for immunotherapy was conducted.

RESULTS

Patients with high NCPG_score were characterized by high tumor mutation burden and high microsatellite instability and were more suitable for immunotherapy.

CONCLUSIONS

This study screened 29 NCPGs as independent prognostic markers in colon cancer patients, demonstrating their TME, clinicopathological features, and potential roles in immunotherapy, helping to assess prognosis and guiding more personalized immunotherapy.

Preoperative computed tomography assessment of circumferential resection margin in retroperitonealized colon cancer predicts disease-free survival

OBJECTIVES

The aim of this retrospective study was to predict circumferential resection margin (CRM) involvement on preoperative CT, and prognostic impact of CRM assessment by CT (ctCRM) in patients with retroperitonealized colon cancer.

METHODS

This study included patients who underwent resection for ascending or descending colon cancer between July 2010 and February 2013. Positive ctCRM was defined as tumor distance to the retromesenteric plane of ≤ 1 mm. The origin of positive CRM was divided into primary tumor or other tumor components including lymph nodes, tumor deposits, or extramural venous invasions. Logistic regression analysis was performed to identify preoperative factors to predict pathologic CRM (pCRM). A Cox proportional hazards model was used in multivariable analysis to determine the preoperative factors affecting disease-free survival (DFS).

RESULTS

A total of 274 patients (mean age, 64.0 years ± 11.0 [standard deviation]; 157 men) with retroperitonealized colon cancer were evaluated. Of 274 patients, 67 patients (24.5%) had positive CRM on surgical pathology. The accuracy of preoperative CT in predicting pCRM was 79.6% (218/274). Among preoperative factors, only CRM assessment on CT was independently associated with pCRM (p < 0.001). Positive ctCRM by primary tumor was an independent factor for DFS (HR, 3.362 [1.714-6.593]) and systemic recurrence (HR, 3.715 [1.787-7.724], but not for local recurrence on multivariable analyses.

CONCLUSIONS

Preoperative CT can accurately predict pCRM, and positive ctCRM by primary tumor is an independent risk factor for DFS and systemic recurrence, but not for local recurrence in retroperitonealized colon cancer.

KEY POINTS

• Preoperative CT can predict pathologic circumferential resection margin (CRM) with approximately 80% of accuracy in patients with retroperitonealized colon cancer. • Positive CRM by a primary tumor on preoperative CT is a poor prognostic factor for disease-free survival and systemic recurrence in patients with retroperitonealized colon cancer. • CRM involvement on CT was not associated with local recurrence in patients with retroperitonealized colon cancer.

A decreased preoperative platelet-to-lymphocyte ratio, systemic immune-inflammation index, and pan-immune-inflammation value are associated with the poorer survival of patients with a stent inserted as a bridge to curative surgery for obstructive colorectal cancer

PURPOSE

Inflammation is one of the hallmarks of cancer, and inflammation-based markers that are calculated easily from laboratory results have shown predictive abilities. We investigated the prognostic values of the preoperative platelet-to-lymphocyte ratio (PLR), systemic immune-inflammation index (SII), and pan-immune-inflammation value (PIV) in patients with non-metastatic obstructive colorectal cancer (OCRC) and a self-expandable metallic stent inserted as a bridge to curative surgery.

METHODS

The subjects of this retrospective study were 86 patients with pathological stage I to III OCRC. We examined the associations of these biomarkers with short- and long-term outcomes.

RESULTS

Multivariate analyses revealed that a preoperative PLR < 149, SII < 597, and PIV < 209 were independently associated with poorer relapse-free survival (RFS) (P = 0.007, P < 0.001, and P = 0.002, respectively) and that a PIV < 209 was independently associated with poorer cancer-specific survival (P = 0.030). A platelet count < 240 was significantly associated with worse RFS, whereas the lymphocyte count was not. Pre-stenting PLR < 221 was an independent poor prognostic factor for RFS (P = 0.045).

CONCLUSION

This study showed that decreased preoperative PLR, SII, PIV, and pre-stenting PLR were associated with poorer RFS, contrary to the findings of most previous studies. Our results suggest that platelets and obstruction contributed primarily to the opposite relationships, which might provide new insight into the possible pathophysiology of platelet-tumor interactions generated in the OCRC environment.

Risk Factors for Severe Postoperative Complications after Oncologic Right Colectomy: Unicenter Analysis

Background and Objectives: This study aimed to investigate the potential risk factors for severe postoperative complications after oncologic right colectomy. Materials and Methods: All consecutive patients with right colon cancer who underwent right colectomy in our department between 2016 and 2021 were retrospectively included in this study. The Clavien-Dindo grading system was used to evaluate postoperative complications. Univariate and multivariate logistic regression analyses were used to investigate risk factors for postoperative severe complications. Results: Of the 144 patients, there were 69 males and 75 females, with a median age of 69 (IQR 60-78). Postoperative morbidity and mortality rates were 41.7% (60 patients) and 11.1% (16 patients), respectively. The anastomotic leak rate was 5.3% (7 patients). Severe postoperative complications (Clavien-Dindo grades III-V) were present in 20 patients (13.9%). Univariate analysis showed the following as risk factors for postoperative severe complications: Charlson score, lack of mechanical bowel preparation, level of preoperative proteins, blood transfusions, and degree of urgency (elective/emergency right colectomy). In the logistic binary regression, the Charlson score (OR = 1.931, 95% CI = 1.077-3.463, p = 0.025) and preoperative protein level (OR = 0.049, 95% CI = 0.006-0.433, p = 0.007) were found to be independent risk factors for postoperative severe complications. Conclusions: Severe complications after oncologic right colectomy are associated with a low preoperative protein level and a higher Charlson comorbidity index.

Comparison of Oncologic Outcomes Between Incomplete Obstructive Colon Cancer and Non-Obstructive Colon Cancer by Tumor Location

Introduction

Obstruction in colon cancer is a well-known risk factor for worse oncologic outcomes. However, studies on differences in survival of patients with incomplete obstructive colon cancer (IOCC) by tumor location are insufficient. Thus, the aim of this study was to compare oncologic outcomes between IOCC and non-obstructive colon cancer (NOCC) according to tumor location.

Methods

From January 2010 to December 2015, a total of 2,004 patients diagnosed with stage II or stage III colon adenocarcinoma who underwent elective colectomy were included (IOCC, n = 405; NOCC, n = 1,599). Incomplete obstruction was defined as a state in which colonoscopy could not pass through the cancer lesion but did not require emergent surgery, stent insertion, or stoma formation because the patient was asymptomatic without problem in bowel preparation. Kaplan–Meier method and log-rank tests were used to compare survival between IOCC and NOCC. Multivariable analysis was performed to determine which factors affected survivals.

Results

Stage III IOCC patients showed significantly lower overall survival (OS) and recurrence-free survival (RFS). Stage II IOCC patients and stage III NOCC patients had similar survival curves. IOCC patients with tumors on the right side showed worse OS than other patients. In multivariable analysis, incomplete obstruction was an independent risk factor for worse OS and RFS in all stages. Tumor located at the right side in stage III was an independent risk factor for RFS (HR: 1.40, p = 0.030).

Conclusions

Patients with IOCC showed significantly worse survival outcomes than those with NOCC. Stage II IOCC patients and stage III NOCC patients showed similar survival. Patients with stage III IOCC located at the right side showed significantly worse oncologic outcomes than those located at the left side. These results confirm that prognosis is different depending on the presence of incomplete obstruction and the location of the tumor, even in the same stage.

Is Adjuvant Chemotherapy Necessary for Obstructing Stage II Colon Cancer? Results From a Propensity Score Analysis of the French Surgical Association Database

OBJECTIVE

The aim of this study was to compare the survival of patients with stage II obstructing colon cancer (OCC) who had adjuvant chemotherapy with those who did not.

SUMMARY BACKGROUND DATA

The need for adjuvant chemotherapy in stage II colon cancer is still debated.

METHODS

All consecutive patients treated for a stage II OCC in a curative intent (with primary tumor resection) between January 2000 and December 2015 were included in this retrospective, multicenter cohort study which included a propensity score analysis using an odds of treatment weighting (Average Treatment effect on the Treated, ATT). The endpoint was the comparison between the 2 groups for overall survival (OS) and disease-free survival (DFS) according to whether or not patients received adjuvant chemotherapy.

RESULTS

During the study period, 504 patients underwent a curative colectomy for a stage II OCC. Among these patients, 179 (35.5%) had adjuvant chemotherapy and 325 (64.5%) had no adjuvant treatment. Among the 179 patients who received adjuvant chemotherapy, 108 patients (60%) received oxaliplatin based regimen and 99 patients (55%) completed all scheduled cycles. At multivariate analysis, after weighting by the odds (ATT analysis) and adjustment, adjuvant chemotherapy after resection of a stage II OCC was associated with improvements in OS [hazard ratio (HR) = 0.42 (0.17-0.99), P = 0.0498] and DFS [HR = 0.57 (0.37-0.88), P = 0.0116].

CONCLUSION

This study suggests that adjuvant chemotherapy after curative resection of stage II OCC may improve oncological outcomes.

Recurrence and colon cancer-specific death in patients with large bowel obstruction requiring urgent operation: a competing risks analysis

AIM

Clinical presentation with large bowel obstruction has been proposed as a predictor of poor long-term oncological outcomes after resection for colorectal cancer. This study examines the association between obstruction and recurrence and cancer-specific death after resection for colon cancer.

METHOD

Consecutive patients who underwent resection for colon cancer between 1995 and 2014 were drawn from a prospectively recorded hospital database with all surviving patients followed for at least 5 years. The outcomes of tumour recurrence and colon cancer-specific death were assessed by competing risks multivariable techniques with adjustment for potential clinical and pathological confounding variables.

RESULTS

Recurrence occurred in 271 of 1485 patients who had a potentially curative resection. In bivariate analysis, obstruction was significantly associated with recurrence [hazard ratio (HR) 2.23, CI 1.52-3.26, p < 0.001] but this association became nonsignificant after adjustment for confounders (HR 1.53, CI 0.95-2.46, p = 0.080). Colon cancer-specific death occurred in 238 of 295 patients who had a noncurative resection. Obstruction was not significantly associated with cancer-specific death (HR 1.02, CI 0.72-1.45, p = 0.903). In patients who had a noncurative resection, the competing risks incidence of colon cancer-specific death was not significantly greater in obstructed than in unobstructed patients (HR 1.02, CI 0.72-1.45, p = 0.903).

CONCLUSION

Whilst the immediate clinical challenge of an individual patient presenting with large bowel obstruction must be addressed by the surgeon, the patient's long-term oncological outcomes are unrelated to obstruction per se.

Tumor size improves the accuracy of the prognostic prediction of T4a stage colon cancer

The aim of this study was to evaluate the potential impact of tumor size on the long-term outcome of colon cancer (CC) patients after curative surgery. A total of 782 curatively resected T4a stage CC patients without distant metastasis were enrolled. Patients were categorized into 2 groups according to the best threshold of tumor size: larger group (LG) and smaller group (SG). Propensity score matching was used to adjust for the differences in baseline characteristics. The ideal cutoff point of tumor size was 5 cm. In the multivariate analysis for the whole study series, tumor size was an independent prognostic factor. Patients in the LG had significant lower 5-year overall survival (OS) and relapse-free survival (RFS) rates (OS: 63.5% versus 75.2%, P < 0.001; RFS: 59.5% versus 72.4%, P < 0.001) than those in the SG. After matching, patients in the LG still demonstrated significant lower 5-year OS and RFS rates than those in the SG. The modified tumor-size-node-metastasis (mTSNM) staging system including tumor size was found to be more appropriate for predicting the OS and RFS of T4a stage CC than TNM stage, and the -2log likelihood of the mTSNM staging system was smaller than the value of TNM stage. In conclusion, tumor size was an independent prognostic factor for OS and RFS. We maintain that tumor size should be incorporated into the staging system to enhance the accuracy of the prognostic prediction of T4a stage CC patients.

Measurement of circumferential tumor extent of colorectal cancer on CT colonography: relation to clinicopathological features and patient prognosis after surgery

PURPOSE

To examine the relationship between circumferential tumor extent of colorectal cancer (CRC) on CT colonography (CTC) and clinicopathological features including patient prognosis after surgery.

MATERIALS AND METHODS

This retrospective study performed at our institution from January 2013 to December 2019 enrolled 195 consecutive patients (110 men, 85 women; mean age, 64.7 years) with CRC evaluated by contrast-enhanced CTC before surgery. The circumferential tumor extent rate (CER) was measured by CTC in virtual colon dissection (VCD) mode to examine the relation between the CER and clinicopathological features and patient prognosis.

RESULTS

CER had association with tumor invasion depth (T), nodal involvement (N), distant metastasis (M), and stage. The Kruskal-Wallis tests showed significant difference for T, N and the stage (p < 0.0001, p = 0.0021 and p < 0.0001) and Wilcoxon rank sum test showed significant difference for M (p = 0.0015). According to the log-rank test, there were no significant differences in OS or DFS between patients with high and low CER.

CONCLUSION

Circumferential tumor extent was significantly correlated with TNM categories and stage of CRC, but not with patient prognosis after surgery.

Serum Chemokine CXCL7 as a Potential Novel Biomarker for Obstructive Colorectal Cancer

Due to the lack of typical symptoms and signs and sensitive indicators for early diagnosis of obstructive colorectal cancer (OCRC), it is critically needed to find new novel biomarkers to ameliorate the management of OCRC patients. In this study, 472 blood samples were collected and measured by enzyme-linked immunosorbent assay (ELISA) to investigate the value of serum chemokine ligand 7 (CXCL7) in diagnosis and prognosis for OCRC patients. The median concentrations of CXCL7 in non-OCRC and OCRC were both higher than that in controls (both P < 0.05). Importantly, the median serum concentration of CXCL7 in OCRC was also higher than that in non-OCRC (P < 0.001). In all OCRC patients, the area under the curve (AUC) of CXCL7 was 0.918 with a sensitivity of 86.54% and a specificity of 81.87%. Similarly, the AUC of CXCL7 was 0.684 when the diagnostic test was performed between OCRC and CRC patients. CXCL7 had a higher AUC than other markers. The concentration of CXCL7 in 40 postoperative OCRC patients was higher than normal people and lower than preoperative patients. The median survival time was 62.00 months and the 5-year overall survival (OS) rate of the patients was 51.80% in all 155 OCRC patients. Multivariate Cox proportional hazard regression model analysis showed that high CXCL7 in serum was independent factors associated with poor OS of OCRC patients (HR = 2.216, P = 0.032). These results demonstrate that serum CXCL7 may be a potential biomarker both in diagnosis and prognosis for OCRC patients.

Prognostic role of pre-sarcopenia and body composition with long-term outcomes in obstructive colorectal cancer: a retrospective cohort study

Background

The clinical significance of pre-sarcopenia in colorectal cancer obstruction has not yet been described. The present study aimed to determine the short- and long-term oncologic impacts of pre-sarcopenia in obstructive colorectal cancer.

Methods

We retrospectively analyzed 214 patients with obstructive colon cancer between January 2004 and December 2013. Initial staging computed tomography (CT) scans identified pre-sarcopenia and visceral obesity by measuring the muscle and visceral fat areas at the third lumbar vertebra level. Both short-term postoperative and long-term oncologic outcomes were analyzed.

Results

Among all 214 patients, 71 (33.2%) were diagnosed with pre-sarcopenia. Pre-sarcopenia had a negative oncologic impact in both disease-free survival (DFS) and overall survival (OS), (hazard ratio [HR] = 1.86, 95% confidence interval [CI] 1.04–3.13, p = 0.037, and HR = 1.92, CI 1.02–3.60, p = 0.043, respectively). Visceral adiposity, body mass index (BMI), and neutrophil-lymphocyte ratio (NLR) did not significantly impact DFS and OS.

Conclusion

Pre-sarcopenia is a clinical factor significantly associated with OS and DFS but not with short-term complications in obstructive colorectal cancer. In future, prospective studies should incorporate body composition data in patient risk assessments and oncologic prediction tools.

Right-sided vs. left-sided obstructing colonic cancer: results of a multicenter study of the French Surgical Association in 2325 patients and literature review

PURPOSE

Few studies compared management and outcomes of obstructing colonic cancer (OCC), according to the tumor site. Our aim was to compare patient and tumor characteristics, postoperative and pathological results, and oncological outcomes after emergency management of right-sided vs. left-sided OCC.

METHODS

A national cohort study including all consecutive patients managed for OCC from 2000 to 2015 in French surgical centers members of the French National Surgical Association (AFC).

RESULTS

During the study period, 2325 patients with OCC were divided in right-sided (n = 819, 35%) and left-sided (n = 1506, 65%) locations. Patients with right-sided OCC were older, more frequently females, and associated with comorbidities, history of cancer, or previous laparotomy. Surgical management was more frequently performed for right-sided than left-sided OCC (99 vs. 96%, p < 0.0001). Tumor resection was more frequently performed in right-sided OCC (95 vs. 90%, p < 0.0001). Among the resected patients, primary anastomosis was more frequently performed in case of right-sided OCC (86 vs. 62%, p < 0.0001). Definitive stoma rate was lower in right-sided location (17 vs. 46%, p < 0.0001). There was no significant difference between locations in terms of cumulative morbidity, anastomotic leak, unplanned reoperation, and mortality. Five-year overall and disease-free survival rates were significantly lower in right-sided OCC (43 and 36%) than in left-sided OCC (53 and 46%, p < 0.0001 and p = 0.001, respectively).

CONCLUSIONS

Although patients with right-sided OCC are frailer than left-sided OCC, tumor resection and anastomosis are more frequently performed, without difference in surgical results. However, right-sided OCC is associated with worse prognosis than distal location.

Surgical management of obstructive right-sided colon cancer at a national level results of a multicenter study of the French Surgical Association in 776 patients

AIM

To report the results of surgery for obstructive right colon cancer (ORCC) and to identify risk factors associated with worse outcomes that may help surgeons to choose the best surgical option.

METHODS

This is a retrospective national cohort study, including all patients operated on for ORCC from 2000 to 2015. Those treated with colonic stent or symptomatic treatment were excluded. We described outcomes after surgery for ORCC and performed multivariate analyses for mortality, morbidity and survival.

RESULTS

Among 776 patients analyzed, 716 (92%) had their primary tumor removed, with primary anastomosis in 582 (82%). The remaining 194 underwent anastomosis with loop ileostomy (n = 21), resection with double-end stoma (n = 113), defunctioning stoma without resection (n = 48) and ileocolic by-pass (n = 12). Postoperative mortality, morbidity and anastomotic leak rates were 10%, 51% and 14%, respectively. In multivariate analysis, age >70, ASA score ≥3 and hemodynamic instability were predictors of postoperative mortality whereas ASA score ≥3, hemodynamic instability and intra-operative complications were predictors of severe morbidity. No factors were correlated with anastomotic leak. After a median follow-up of 26 months, 8% of patients were alive with a permanent stoma. Five-year overall, disease-free and cancer-specific survival was 42%, 42% and 62%, respectively. In multivariate analysis, peritonitis, synchronous metastases and absence of adjuvant chemotherapy were predictors of decreased overall survival.

CONCLUSIONS

Emergency surgery for ORCC is associated with high mortality and morbidity. Two third of patients with ORCC can be managed with resection and primary anastomosis. For high-risk patients, a staged surgical management may be discussed.

Emergency surgery for obstructing colonic cancer: a comparison between right-sided and left-sided lesions

PURPOSE

Few studies compare management and outcomes of obstructive colonic cancer, depending on the tumor site. We aim to evaluate the differences in patient characteristics, tumor characteristics, and outcomes of emergency surgery for obstructive right-sided versus left-sided colonic cancers.

METHODS

Between 2000 and 2009, 71 consecutive patients had an emergency colectomy following strict and clear definition of obstruction in a single institution. We retrospectively analyzed pre, per, and postoperative data that were prospectively collected.

RESULTS

There were 31 and 40 patients in the right and left group, respectively. Patients aged over 80 were more frequent in the right group (p = 0.03). At operation, ileocecal valve was less often competent in the right group (p = 0.03). The one-stage strategy was more frequent in the right group (p = 0.008). Patients in the right group had a higher rate of nodes invasion (p = 0.04). One- and two-year mortality rate in the right group had a tendency to be higher.

CONCLUSIONS

Patients presenting with a right obstructive colonic cancer are older, have a more advanced locoregional disease, and are more often treated in a one-stage strategy than patients with a left obstructive tumor.

Long-term outcomes and prognostic factors of patients with obstructive colorectal cancer: A multicenter retrospective cohort study

AIM: To investigate the long-term oncologic outcomes and prognostic factors in patients with obstructive colorectal cancer (CRC) at multiple Japanese institutions.

METHODS: We identified 362 patients diagnosed with obstructive colorectal cancer from January 1, 2002 to December 31, 2012 in Yokohama Clinical Oncology Group’s department of gastroenterological surgery. Among them, 234 patients with stage II/III disease who had undergone surgical resection of their primary lesions were analyzed, retrospectively. We report the long-term outcomes, the risk factors for recurrence, and the prognostic factors.

RESULTS: The five-year disease free survival and cancer-specific survival were 50.6% and 80.3%, respectively. A multivariate analysis showed the ASA-PS (HR = 2.23, P = 0.026), serum Albumin ≤ 4.0 g/dL (HR = 2.96, P = 0.007), T4 tumor (HR = 2.73, P = 0.002) and R1 resection (HR = 6.56, P = 0.02) to be independent risk factors for recurrence. Furthermore, poorly differentiated cancers (HR = 6.28, P = 0.009), a T4 tumor (HR = 3.46, P = 0.011) and R1 resection (HR = 6.16, P = 0.006) were independent prognostic factors in patients with obstructive CRC.

CONCLUSION: The outcomes of patients with obstructive CRC was poor. T4 tumor and R1 resection were found to be independent prognostic factors for both recurrence and survival in patients with obstructive CRC.

Emergency resection versus bridge to surgery with stenting in patients with acute right-sided colonic obstruction: a systematic review focusing on mortality and morbidity rates

PURPOSE

No consensus exists on the optimal treatment of acute malignant right-sided colonic obstruction (RSCO). This systematic review aims to compare procedure-related mortality and morbidity rates between primary resection and stent placement as a bridge to surgery followed by elective resection for patients with acute RSCO.

METHODS

PubMed, Embase and Cochrane library were searched for all relevant literature. Primary endpoints were procedure-related mortality and morbidity. Methodological quality of the included studies was assessed using the MINORS criteria.

RESULTS

Fourteen cohort studies were eligible for analysis. A total of 2873 patients were included in the acute resection group and 155 patients in the stent group. Mean mortality rate for patients who underwent acute resection with primary anastomosis was 10.8% (8.1-18.5%). Overall mortality for patients initially treated with a colonic stent followed with elective resection was 0%. Major morbidity was 23.9% (9.3-35.6%) and 0.8% (0-4.8%), respectively. Both mortality and major morbidity were significantly different. In addition, stent placement shows lower rates of anastomotic leakages (0 vs 9.1%) and fewer permanent ileostomies (0 vs 1.0%).

CONCLUSION

Primary resection for patients with acute RSCO seems to be associated with higher mortality and major morbidity rates than stent placement and elective resection. In addition, stent placement resulted in fewer anastomotic leakages and permanent ileostomies. However, as no high-level studies are available on the optimal treatment of RSCO and proximal stenting is considered technically challenging, future comparative studies are warranted for the development of an evidence-based clinical decision guideline.

Risk of recurrence in patients with colon cancer stage II and III: a systematic review and meta-analysis of recent literature

BACKGROUND

Adjuvant chemotherapy is established routine therapy for colon cancer (CC) patients with radically resected stage III and 'high-risk' stage II disease. The decision on recommending adjuvant chemotherapy, however, is based on data from older patient cohorts not reflecting improvements in pre-operative staging, surgery, and pathological examination. The aim is to review the current risk of recurrence in stage II and III patients and second, to estimate the relative importance of routinely assessed clinico-pathological variables.

METHODS

The PubMed/MEDLINE and the Cochrane databases were systematically searched for randomized controlled studies and observational studies published after 1 January 2005 with patients included after January 1995 on prognosis in surgically treated stage II and III CC patients.

RESULTS

Of 2596 studies identified, 37 met the inclusion criteria and 25 provided data for meta-analysis. The total patient sample size in the 25 studies reporting either disease-free (DFS) or recurrence-free survival was 15 559 in stage II and 18 425 in stage III. Five-year DFS for stage II patients operated without subsequent adjuvant chemotherapy was 81.4% [95% confidence interval (CI) 75.4-87.4; in studies with good/very good quality of reporting 82.7%, (95% CI 80.8-84.6)]. For stage II patients treated with adjuvant chemotherapy, the five-year DFS was 79.3% (95% CI 75.6-83.1). For stage III patients without chemotherapy, five-year DFS was 49.0% (95% CI 23.2-74.8) and for those treated with adjuvant chemotherapy, 63.6% (95% CI 59.3-67.9). The prognostic impact of commonly investigated clinico-pathological parameters, (pT-stage, pN-stage, differentiation, number of lymph nodes studied, MMR-status, and emergency surgery) were confirmed.

CONCLUSIONS

In this meta-analysis, studies with good quality of reporting show a five-year DFS of 82.7% for stage II CC without adjuvant chemotherapy, whereas the five-year DFS is 63.8% for stage III CC with adjuvant chemotherapy. Due to insufficient reporting on treatment quality the presented DFS is likely an under-estimation of what is achieved at high-quality centers today.

A systematic review of outcome reporting in colorectal cancer surgery

AIM

Evaluation of surgery for colorectal cancer (CRC) is necessary to inform clinical decision-making and healthcare policy. The standards of outcome reporting after CRC surgery have not previously been considered.

METHOD

Systematic literature searches identified randomized and nonrandomized prospective studies reporting clinical outcomes of CRC surgery. Outcomes were listed verbatim, categorized into broad groups (outcome domains) and examined for a definition (an appropriate textual explanation or a supporting citation). Outcome reporting was considered inconsistent if results of the outcome specified in the methods were not reported. Outcome reporting was compared between randomized and nonrandomized studies.

RESULTS

Of 5644 abstracts, 194 articles (34 randomized and 160 nonrandomized studies) were included reporting 766 different clinical outcomes, categorized into seven domains. A mean of 14 ± 8 individual outcomes were reported per study. 'Anastomotic leak', 'overall survival' and 'wound infection' were the three most frequently reported outcomes in 72, 60 and 44 (37.1%, 30.9% and 22.7%) studies, respectively, and no single outcome was reported in every publication. Outcome definitions were significantly more often provided in randomized studies than in nonrandomized studies (19.0% vs 14.9%, P = 0.015). One-hundred and twenty-seven (65.5%) papers reported results of all outcomes specified in the methods (randomized studies, n = 21, 61.5%; nonrandomized studies, n = 106, 66.2%; P = 0.617).

CONCLUSION

Outcome reporting in CRC surgery lacks consistency and method. Improved standards of outcome measurement are recommended to permit data synthesis and transparent cross-study comparisons.

Colonization of the human gut by E. coli and colorectal cancer risk

PURPOSE

The intestinal microbiota is potentially involved in the development of colorectal carcinoma via various mechanisms. Escherichia coli are commensal bacteria of the human gut microbiota, but some pathogenic strains have acquired the ability to induce chronic inflammation and/or produce toxins, such as cyclomodulin, which could participate in the carcinogenesis process. Here, we analyzed the E. coli population associated with mucosa of patients with colon cancer in relation to clinicopathologic characteristics. We assessed carcinogenic properties of a colon cancer-associated E. coli strain in multiple intestinal neoplasia (Min) mice.

EXPERIMENTAL DESIGN

Mucosa-associated or internalized E. coli were quantified and characterized from tumors and mucosa of patients with colon cancer and the healthy mucosa of diverticulosis controls. Min mice were inoculated with a colon cancer-associated E. coli strain (11G5). The number of colonic polyps was evaluated at 7 weeks after infection.

RESULTS

An increased level of mucosa-associated and internalized E. coli was observed in the tumors compared with normal tissue. A relationship between poor prognostic factors for colon cancer (tumor-node-metastasis stage) and colonization of mucosa by E. coli was observed. Pathogenic cyclomodulin-positive E. coli strains were more prevalent on mucosa of patients with stages III/IV than those with stage I colon cancer. Proliferative index and E. coli colonization level of the mucosa distant from the tumor significantly correlated. Min mice infected with the E. coli strain 11G5 displayed a marked increase in the number of visible colonic polyps compared with controls.

CONCLUSION

These findings support that pathogenic E. coli could be a cofactor in pathogenesis of colorectal cancer.

Identification of high-risk factors as indicators for adjuvant therapy in stage II colon cancer patients treated at a single institution

Although post-operative adjuvant chemotherapy (ACT) is only recommended for patients with stage II colon cancer who are at a high risk of recurrence, the definition of high risk remains unclear. The present study aimed to identify the risk factors for recurrence, which may also be indicators for adjuvant therapy, using a retrospective analysis of clinicopathological data obtained from stage II colon cancer patients who had undergone a curative resection. The present study also investigated the effects of ACT in patients who displayed the risk factors for recurrence. Univariate and multivariate analyses of the data collected from 377 stage II colon cancer patients, treated at Kurume University Hospital (Fukuoka, Japan) between 1982 and 2005, was conducted in order to determine and compare the risk factors for recurrence between the 163 patients who had undergone adjuvant therapy and the 214 patients who had not undergone adjuvant therapy. The risk factors for recurrence in patients who had not undergone adjuvant therapy were a serum carcinoembryonic antigen (CEA) level that was twice the cut-off value and pre-operative bowel obstruction. Adjuvant therapy provided no benefit to patients who presented with neither risk factor, but significantly decreased the recurrence rate in patients presenting with one or both risk factors. Based on these findings, serum CEA levels of twice the cut-off value and pre-operative bowel obstruction were proposed as indicators in the assessment for adjuvant chemotherapy following a curative resection for stage II colon cancer. These results warrant further clinical study of ACT in patients with one or both risk factors.

Iron-deficiency anemia: a predictor of diminished disease-free survival of T3N0M0 stage colon cancer

PURPOSE

The aim of this study was to determine whether iron-deficiency anemia (IDA) predicts long-term oncologic outcomes in patients with TNM stage II colon cancer.

METHODS

Clinical and follow-up data were extracted from a prospective colon cancer database. Univariate and multivariate analyses were performed to identify IDA and other predictors of long-term oncologic outcomes.

RESULTS

Among 644 patients, 147 (22.8%) patients presented with IDA. The data were stratified by T3N0M0 and T4N0M0. The distribution difference of IDA between the two subsets was not significant (P = 0.340). But in the T4N0M0 subset, the incidence of IDA increased with the depth of tumor penetration (75.9% and 18.2% for the patients with and without adjacent organ involvement, respectively, P = 0.011). IDA predicted a worse disease-free survival among patients with T3N0M0 cancer (472 patients; log-rank test, P = 0.016; Cox regression, P = 0.009), but it was not a predictor in T4N0M0 cancer patients (172 patients; log-rank test, P = 0.016; Cox regression, P > 0.05).

CONCLUSIONS

IDA was an independent predictor of long-term outcome in T3N0M0 stage, but not in T4N0M0 colon cancer. T3N0M0 stage colon cancer patients with IDA could be included in future trials of adjuvant therapies.

Differences between proximal and distal obstructing colonic cancer after curative surgery

AIM

To study any possible differences in morbidity, mortality and overall survival rate after curative surgery for obstructive colon cancer according to tumour location.

METHOD

From January 1994 to December 2006, patients with colonic cancer presenting as obstruction were analysed. The two groups were defined as proximal and distal according to the tumour location with respect to the splenic flexure. In relation to the surgeon specialization, patients were operated on by a colorectal surgeon and by a general surgeon. Postoperative morbidity and mortality and cancer-related survival at 3 years were analysed.

RESULTS

Of the 377 patients included in the study, there were 173 patients (45.9%) in the proximal group and 204 patients (54.1%) in the distal group. The global morbidity was 54.9% without differences in postoperative morbidity except for anastomotic leakage, which was higher in the proximal group (P < 0.014). No differences in postoperative mortality were observed. After patients were stratified by the tumour node metastasis system, the differences between the groups, with respect to 3-year overall survival, cancer-related survival and probability of being free from recurrence, did not reach statistical significance. The overall survival after radical surgery for colonic obstruction was 57.6%.

CONCLUSION

Mortality and morbidity after emergency surgery for obstructing colon cancer are high. Specialization in colorectal surgery influences postoperative results in terms of lower anastomotic dehiscence rate after emergency proximal colon resection. After radical surgery, tumour location does not appear to influence the prognosis of obstructive colon cancer.