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

Comparison of postoperative prognoses for resectable colorectal cancer with vs. without oncologic emergency using propensity score‑matched analyses: A single-center retrospective observational study

While oncological emergencies in colorectal cancer present distinct challenges, existing literature offers conflicting evidence regarding long-term outcomes. Therefore, the present study compared the postoperative prognoses between patients with and without oncological emergencies. A retrospective evaluation was conducted on patients who had undergone radical surgery for pathological stages II and III colorectal cancer at a single center between January 2012 and December 2020. Patients were classified into the non-emergency and oncological emergency groups. The status of oncologic emergency was divided into obstruction and perforation. The outcomes were compared using propensity score matching. The primary objective was to compare the postoperative prognoses between non-emergency and oncological emergency situations. The secondary objectives included comparing prognoses between obstruction and perforation, identifying the type of recurrence depending on the status of oncologic emergency, and assessing the effect of adjuvant chemotherapy for oncologic emergencies. This study included 524 patients. After propensity score matching, the prognoses of oncological emergencies were worse compared with those without any emergency, whereas those of obstruction and perforation did not significantly differ. Regarding the type of recurrence, peritoneal dissemination in obstruction and local recurrence in perforation was more common compared with that in non-emergency cases. Adjuvant chemotherapy improved the recurrence-free survival for cases with oncological emergencies. The prognoses in cases with oncological emergencies could be worse compared with those without any emergency, whereas obstruction and perforation outcomes can be comparable. The administration of adjuvant chemotherapy should be strongly considered for oncological emergencies.

Complete Obstruction, a Real Risk Factor: A Comprehensive Study on Obstruction in Stage IIA Colon Cancer With Propensity Score Matching Analysis

MICROABSTRACT

This study evaluates the prognostic significance of obstructions in stage IIA colon cancer, distinguishing between partial and complete obstructions. It employs a retrospective review of 1914 patients with propensity score matching to analyze oncologic outcomes. Findings reveal complete obstruction as a significant risk factor for poorer outcomes, emphasizing the necessity for further research to refine treatment strategies, particularly regarding the efficacy of adjuvant chemotherapy across obstruction types.

BACKGROUND

This study examined the prognostic impact of obstructions in stage IIA colon cancer. The analysis specifically differentiated partial and complete obstructions, analyzing their distinct influences of both on oncologic outcomes.

MATERIALS AND METHODS

A retrospective review was conducted of stage IIA colon cancer cases with the presence of an obstruction. Patients were stratified by whether it was partial or complete based on the severity of obstruction. Propensity score matching was employed to control for confounders.

RESULTS

Among 1914 consecutive patients diagnosed with stage IIA colon cancer, 758 patients (597 patients with partial obstruction, 161 patients with complete obstruction) exhibited obstruction, while 1156 patients had no obstruction. The median follow-up period was 126 months. Complete obstruction was associated with poorer disease-free survival (Hazard ratio (HR) = 1.785, P < .001) and overall survival (HR = 1.853, P = .001). This trend persisted after propensity score matching, patients with complete obstruction showing a worsened disease-free survival (HR = 1.666, P = .028) and overall survival (HR = 1.732, P = .041). Adjuvant chemotherapy showed improved outcomes overall, but its efficacy varied across obstruction types.

CONCLUSION

Differentiating between complete and partial obstructions in stage IIA colon cancer is an important clinical distinction, as our findings suggest that complete obstruction is a significant risk factor for poorer oncologic outcomes. While adjuvant chemotherapy generally improves prognosis in stage IIA colon cancer, the correlation of obstruction type with its efficacy remains uncertain, necessitating further research to refine treatment strategies.

Predictive modelling for high-risk stage II colon cancer using auto-artificial intelligence

BACKGROUND

Recently, stratification of high-risk stage II colon cancer (CC) and the need for adjuvant chemotherapy have been the focus of attention. The aim of this retrospective study was to define high-risk factors for recurrent stage II CC using Prediction One auto-artificial intelligence (AI) software and develop a new predictive model for high-risk stage II CC.

METHODS

The study included 259 consecutive pathological stage II CC patients undergoing curative resection at our institution between January 2000 and December 2016. Prediction One software with five-fold cross-validation was used to create a predictive model and receiver operating characteristic (ROC) curve. Predictive accuracy of AI was evaluated using the area under the ROC curve (AUC). We also evaluated the importance of variables (IOV) using a method based on permutation feature importance (IOV > 0.01 defined high-risk factors) to evaluate disease-free survival (DFS).

RESULTS

The median observation period was 6.1 (range = 0.3-15.8) years. Thirty-seven patients had recurrence (14.3%); the AUC of the AI model was 0.775. Preoperative carcinoembryonic antigen > 5.0 ng/mL (IOV = 0.047), venous invasion (IOV = 0.014), and obstruction (IOV = 0.012) were high-risk factors contributing to cancer recurrence. Patients with 2-3 high-risk factors had lower 5-year DFS than those with 0-1 factor (87.4% vs 62.7%, p < 0.001).

CONCLUSIONS

We developed a new predictive model that could predict recurrent high-risk stage II CC with high probability using auto-AI Prediction One software. Patients with ≥ 2 of the aforementioned factors are considered to have high risks for recurrent stage II CC and may benefit from adjuvant chemotherapy.

Can clinicopathologic high-risk features in T3N0 colon cancer be reliable prognostic factors?

Purpose

The purpose of this study was to assess the reliability and prognostic significance of the high-risk feature (HRF) in patients with T3N0 colon cancer.

Methods

We included 1,205 patients with pT3N0 colon cancer treated with curative radical resection between 2012 and 2016. HRF was defined as lymphovascular invasion, perineural invasion, poorly/undifferentiated histology, margin involvement, and preoperative obstruction. We investigated the relationships between the number and type of HRF and recurrence-free survival (RFS) and overall survival (OS), as well as the effect of adjuvant treatment.

Results

A total of 751 of the patients (62.3%) had more than 1 HRF and 515 of the patients (42.7%) underwent adjuvant treatment. Patients who had more than 2 HRFs had a significantly worse 5-year RFS and OS compared to patients who had neither HRF nor even one HRF. According to the findings of the multivariate analysis, the presence of multiple HRFs was a risk factor for a lower RFS and OS. When the quantity and type of HRF were taken into consideration in the multivariate analysis, adjuvant chemotherapy was not found to be linked with RFS or OS in patients with pT3N0 colon cancer.

Conclusion

In the present study, adjuvant treatment based on the current guideline of treatment indication was unable to enhance the prognosis of patients with pT3N0 colon cancer. The role of adjuvant treatment in T3N0 colon cancer must be examined with the HRF count in mind.

Prognostic Implications of Endoscopic Obstruction in Patients with Pathological Stage II Colon Cancers: a Single-Center Retrospective Cohort Study

BACKGROUND

The prognostic effect of endoscopic obstruction (eOB) on the survival of stage II colon cancer patients and the role of eOB in guiding postoperative adjuvant chemotherapy of stage II colon cancer are little known.

METHODS

In this retrospective, single-center cohort study, patients who had undergone curative surgery and preoperative colonoscope for stage II colon carcinoma were included. The eOB was defined as severe luminal colon obstruction that prevented the standard colonoscope from passing beyond the tumor. The association between eOB and stage II colon cancer survival and the predictive role of eOB for adjuvant chemotherapy were evaluated using multivariate Cox regression analysis.

RESULTS

Of 1102 included patients, 616 (55.9%) had eOB and 486 (44.1%) had no eOB. The median follow-up was 49 months (interquartile range, 38-68 months). Kaplan-Meier curves showed that patients with eOB had poor 5-year overall survival (OS; 85.3% vs. 95.3%, p < 0.001) compared to patients without eOB. Five-year disease-free survival (DFS; 78.5% vs. 87.6%, p = 0.004) was also poor in these patients. Multivariate analysis demonstrated eOB was a significant prognostic factor for poor OS (hazard ratio [HR] = 2.531, p < 0.001), but not for DFS (p = 0.081). Even when patients with clinical colonic obstruction were excluded from the population with eOB, the worse OS (HR = 2.262, p = 0.001) was observed. The OS and DFS of eOB patients improved slightly after adjuvant chemotherapy, but there was no statistical significance.

CONCLUSIONS

Stage II colon cancer patients with eOB have a poor prognosis. However, whether eOB can guide adjuvant chemotherapy still needs further study.

Adjuvant Therapy for Stage II Colon Cancer: ASCO Guideline Update

PURPOSE

To develop recommendations for adjuvant therapy for patients with resected stage II colon cancer.

METHODS

ASCO convened an Expert Panel to conduct a systematic review of relevant studies and develop recommendations for clinical practice.

RESULTS

Twenty-one observational studies and six randomized controlled trials met the systematic review inclusion criteria.

RECOMMENDATIONS

Adjuvant chemotherapy (ACT) is not routinely recommended for patients with stage II colon cancer who are not in a high-risk subgroup. Patients with T4 tumors are at higher risk of recurrence and should be offered ACT, whereas patients with other high-risk factors, including sampling of fewer than 12 lymph nodes in the surgical specimen, perineural or lymphatic invasion, poorly or undifferentiated tumor grade, intestinal obstruction, tumor perforation, or grade BD3 tumor budding, may be offered ACT. The addition of oxaliplatin to fluoropyrimidine-based ACT is not routinely recommended, but may be offered as a result of shared decision making. Patients with mismatch repair deficiency/microsatellite instability tumors should not be routinely offered ACT; if the combination of mismatch repair deficiency/microsatellite instability and high-risk factors results in a decision to offer ACT, oxaliplatin-containing chemotherapy is recommended. Duration of oxaliplatin-containing chemotherapy is also addressed, with recommendations for 3 or 6 months of treatment with capecitabine and oxaliplatin or fluorouracil, leucovorin, and oxaliplatin, with decision making informed by key evidence of 5-year disease-free survival in each treatment subgroup and the rate of adverse events, including peripheral neuropathy.Additional information is available at www.asco.org/gastrointestinal-cancer-guidelines.

Emergency surgery for obstructive splenic flexure colon cancer: results of a multicentric study of the French Surgical Association (AFC)

Management of malignant left-sided colonic obstruction remains challenging and requires a stoma in 40-65% of patients. In those with obstructive splenic flexure colon cancer (OSFCC), a debate still exists regarding the most appropriate surgery. The aim of this muticenter study was to report and compare the different surgical procedures in OSFCC patients with a special focus on operative and histological characteristics and survival outcomes including 12-month stoma-free survival. Between 2000 and 2015, 2325 patients were treated for obstructive colon cancer in centers members of the French National Surgical Association (AFC). Among them, 198 underwent surgery for OSFCC and were retrospectively analyzed. Patients with OSFCC and proximal colonic ischemia or perforation were excluded. Four procedures were performed: decompressing stoma (DS, 39%), splenic flexure colectomy (SFC, 39%), subtotal colectomy (STC, 17%,) and left hemicolectomy (LHC, 5%). All patients treated with LHC underwent a Hartmann's procedure. There was no significant difference between groups for postoperative mortality and morbidity. Hospital stay was significantly longer after DS. The length of the specimen, longitudinal resection margins and number of harvested lymph nodes were significantly higher in the STC group. There was no difference for overall and disease-free survival. Stoma-free survival was significantly lower after LHC (62%) in comparison with the other groups (p < 0.0001). At the end of follow-up, 50% of patients who underwent LHC had a permanent stoma. In OSFCC patients without proximal colonic ischemia or peritonitis, LHC should no longer be recommended due to a high risk of permanent stoma.

Assessment of indocyanine green tracer-guided lymphadenectomy in laparoscopic gastrectomy after neoadjuvant chemotherapy for locally advanced gastric cancer: results from a multicenter analysis based on propensity matching

BACKGROUND

This study evaluated the safety, effectiveness, and feasibility of indocyanine green (ICG) tracing in guiding lymph-node (LN) dissection during laparoscopic D2 radical gastrectomy in patients with advanced gastric cancer (AGC) after neoadjuvant chemotherapy (NAC).

METHOD

We retrospectively analyzed data on 313 patients with clinical stage of cT1-4N0-3M0 who underwent laparoscopic radical gastrectomy after NAC between February 2010 and October 2020 from two hospitals in China. Grouped according to whether ICG was injected. For the ICG group (n = 102) and non-ICG group (n = 211), 1:1 propensity matching analysis was used.

RESULTS

After matching, there was no significant difference in the general clinical pathological data between the two groups (ICG vs. non-ICG: 94 vs. 94). The average number of total LN dissections was significantly higher in the ICG group and lower LN non-compliance rate than in the non-ICG group. Subgroup analysis showed that among patients with LN and tumor did not shrink after NAC, the number of LN dissections was significantly more and LN non-compliance rate was lower in the ICG group than in the non-ICG group. Intraoperative blood loss was significantly lesser in the ICG group than in the non-ICG group, while the recovery and complications of the two groups were similar.

CONCLUSION

For patients with poor NAC outcomes, ICG tracing can increase the number of LN dissections during laparoscopic radical gastrectomy, reduce the rate of LN non-compliance, and reduce intraoperative bleeding. Patients with AGC should routinely undergo ICG-guided laparoscopic radical gastrectomy.

Impact of laparoscopy on oncological outcomes after colectomy for stage III colon cancer: A post-hoc multivariate analysis from PETACC8 European randomized clinical trial

BACKGROUND

In colon cancer (CC), surgery remains the mainstay of treatment with curative intent. Despite several clinical trials comparing open and laparoscopic approaches, data on long-term outcomes for stage III CC are lacking.

METHODS

This post-hoc analysis of the European PETACC8 randomized phase 3 trial included patients from 340 sites between December 2005 and November 2009, with long follow-up (median 7.56 years). Patients were randomly assigned to FOLFOX or FOLFOX+cetuximab after colonic resection. The surgical approach was left to the referring surgeon's discretion.

RESULTS

Among 2555 patients included, 1796 (70.29%) were operated on by open surgery and 759 (29.71%) by laparoscopy. The 5-year OS rate was better after laparoscopic resection (85.4%, 95%CI 82.5-87.7) than after open surgery (80.2%, 95%CI 78.2-82.0; p = 0.002). The 5-year DFS rate was also better after laparoscopy (p = 0.016). However, in multivariate analysis using a propensity matching, the surgical approach was not found to be an independent prognostic factor for OS or DFS. OS (p = 0.0243) and DFS (p = 0.035) were increased after laparoscopic surgery in KRAS/BRAF WT sub-group CONCLUSION: We showed that laparoscopic resection has comparable long-term outcomes to open surgery in patients with stage III CC. For those with RAS and BRAF WT CC, laparoscopic colectomy may favorably impact survival.

Does neoadjuvant FOLFOX chemotherapy improve the prognosis of high-risk Stage II and III colon cancers? Three years' follow-up results of the PRODIGE 22 phase II randomized multicentre trial

AIM

Neoadjuvant chemotherapy has proven valuable in locally advanced resectable colon cancer (CC) but its effect on oncological outcomes is uncertain. The aim of the present paper was to report 3-year oncological outcomes, representing the secondary endpoints of the PRODIGE 22 trial.

METHOD

PRODIGE 22 was a randomized multicentre phase II trial in high-risk T3, T4 and/or N2 CC patients on CT scan. Patients were randomized between 6 months of adjuvant FOLFOX (upfront surgery) or perioperative FOLFOX (four cycles before surgery and eight cycles after; FOLFOX perioperative). In wild-type RAS patients, a third arm testing perioperative FOLFOX-cetuximab was added. The primary endpoint was the tumour regression grade. Secondary endpoints were 3-year overall survival (OS), disease-free survival (DFS), recurrence-free survival (RFS) and time to recurrence (TTR).

RESULTS

Overall, 120 patients were enrolled. At interim analysis, the FOLFOX-cetuximab arm was stopped for futility. The remaining 104 patients represented our intention-to-treat population. In the perioperative group, 96% received the scheduled four neoadjuvant cycles and all but one had adjuvant FOLFOX for eight cycles. In the control arm, 38 (73%) patients received adjuvant FOLFOX. The median follow-up was 54.3 months. Three-year OS was 90.4% in both arms [hazard ratio (HR) = 0.85], 3-year DFS, RFS and TTR were, respectively, 76.8% and 69.2% (HR=0.94), 73% and 69.2% (HR = 0.86) and 82% and 72% (HR = 0.67) in the perioperative and control arms, respectively. Forest plots did not show any subgroup with significant difference for survival outcomes. No benefit from adding cetuximab was observed.

CONCLUSION

Perioperative FOLFOX has no detrimental effect on long-term oncological outcomes and may be an option for some patients with locally advanced CC.