Quasi-elective left colectomy after endoscopic colon stenting for obstructive cancer yields comparable oncologic outcome to full-elective operation

Oncologic oUTcomes of neoadjuvant chemotherapy for obSTructive colon cAncer after steNt decompression (OUTSTAND trial); A study protocol of multicenter non-inferiority randomized controlled trial

BACKGROUND

For obstructive colon cancer, many studies have been conducted on the use of self-expandable metallic stents (SEMS) as a bridge to surgery (BTS). However, there are currently no available prospective data on the impact of bridging period and there is a lack of research on the effects of neoadjuvant chemotherapy during the bridging period.

OBJECTIVES

Patients who undergo successful SEMS placement for obstructive left-sided colon adenocarcinoma without metastases will be eligible for this study.

DESIGN

This study is a multicenter, non-inferiority, randomized (1:1), open-label, controlled trial.

METHODS & ANALYSIS

The patients assigned to the control group will undergo curative surgery within two weeks after successful SEMS placement. The patients assigned to the experimental group will undergo three cycles of neoadjuvant FOLFOX chemotherapy within two weeks after successful SEMS placement. Curative surgery will be performed within four weeks of the last administration of neoadjuvant FOLFOX. Circulating tumor DNA (ctDNA) will be collected at specific time points.

DISCUSSION

The optimal time interval for SEMS placement as a BTS can significantly impact long-term oncologic outcomes. In this study, our goal is to identify the optimal time interval for SEMS placement as a BTS. Recently, there has been interest in applying neoadjuvant chemotherapy for locally advanced colon cancer. In the context of early treatment for tumor dissemination following SEMS placement, neoadjuvant chemotherapy may be beneficial for delayed surgery after SEMS placement as a BTS. The results of this trial will be an important reference for the application of neoadjuvant chemotherapy in locally advanced colon cancer. Additionally, researchers will investigate whether ctDNA can serve as a reliable indicator to guide decisions about the timing and type of subsequent treatment. Based on the results of this trial, a patient-tailored treatment strategy can be developed for obstructive colon cancer.

REGISTRATION

This study is registered on ClinicalTrials.gov Identifier: NCT04889820, registered on May 17, 2021 in clinicaltrials.gov; Protocol ID: XC21MIDI0004.

Colonic stenting in acute malignant large bowel obstruction: audit of efficacy and safety in a Singapore tertiary referral centre

Introduction

Acute malignant large bowel obstruction (MBO) occurs in 8%-15% of colorectal cancer patients. Self-expandable metal stents (SEMS) have progressed from a palliative modality to use as bridge to surgery (BTS). We aimed to assess the safety and efficacy of SEMS for MBO in our institution.

Methods

The data of patients undergoing SEMS insertion for MBO were reviewed. Technical success was defined as successful SEMS deployment across tumour without complications. Clinical success was defined as colonic decompression without requiring further surgical intervention. Rates of complications, median time to surgery, types of surgery and rates of recurrence were studied.

Results

Seventy-nine patients underwent emergent SEMS placement from September 2013 to February 2020. Their mean age was 68.8 ± 13.8 years and 43 (54%) patients were male. Mean tumour length was 4.2 cm ± 2.2 cm; 89.9% of malignant strictures were located distal to the splenic flexure. Technical and clinical success was 94.9% and 98.7%, respectively. Perforation occurred in 5.1% of patients, with none having stent migration or bleeding. Fifty (63.3%) patients underwent SEMS insertion as BTS. Median time to surgery was 20 (range 6-57) days. Most (82%) patients underwent minimally invasive surgery. Primary anastomosis rate was 98%. Thirty-nine patients had follow-up beyond 1-year posttreatment (median 34 months). Local recurrence and distant metastasis were observed in 4 (10.3%) and 5 (12.8%) patients, respectively.

Conclusion

Insertion of SEMS for acute MBO has high success rates and a good safety profile. Most patients in this audit underwent minimally invasive surgery and primary anastomosis after successful BTS.

Perioperative and oncologic outcomes of interval colectomy performed by acute care surgeons after stenting as a bridge to surgery for left-sided malignant colonic obstruction are non-inferior to the outcomes of colorectal surgeons in the elective setting: single center experience

PURPOSE

To analyze if perioperative and oncologic outcomes with stenting as a bridge to surgery (SEMS-BS) and interval colectomy performed by acute care surgeons for left-sided occlusive colonic neoplasms (LSCON) are non-inferior to those obtained by colorectal surgeons for non-occlusive tumors of the same location in the full-elective context.

METHODS

From January 2011 to January 2021, patients with LSCON at University Regional Hospital in Málaga (Spain) were directed to a SEMS-BS strategy with an interval colectomy performed by acute care surgeons and included in the study group (SEMS-BS). The control group was formed with patients from the Colorectal Division elective surgical activity dataset, matching by ASA, stage, location and year of surgery on a ratio 1:2. Stages IV or palliative stenting were excluded. Software SPSS 23.0 was used to analyze perioperative and oncologic (defined by overall -OS- and disease free -DFS-survival) outcomes.

RESULTS

SEMS-BS and control group included 56 and 98 patients, respectively. In SEMS-BS group, rates of technical/clinical failure and perforation were 5.35% (3/56), 3.57% (2/56) and 3.57% (2/56). Surgery was performed with a median interval time of 11 days (9-16). No differences between groups were observed in perioperative outcomes (laparoscopic approach, primary anastomosis rate, morbidity or mortality). As well, no statistically significant differences were observed in OS and DFS between groups, both compared globally (OS:p < 0.94; DFS:p < 0.67, respectively) or by stages I-II (OS:p < 0.78; DFS:p < 0.17) and III (OS:p < 0.86; DFS:p < 0.70).

CONCLUSION

Perioperative and oncologic outcomes of a strategy with SEMS-BS for LSCON are non-inferior to those obtained in the elective setting for non-occlusive neoplasms in the same location. Technical and oncologic safety of interval colectomy performed on a semi-scheduled situation by acute care surgeons is absolutely warranted.

Endoscopic Decompression in Colonic Distension

Background

Acute colonic distension is a medical emergency with high morbidity and mortality. Clinically important causes of colonic distension are acute colonic pseudo-obstruction, colonic volvulus, and malignant obstruction. Endoscopic decompression is one established therapeutic strategy.

Summary

This therapeutic review will give an overview of possible therapeutic strategies based on the recently published literature, focusing on endoscopic decompression and summarizing the other therapeutic possibilities. The review discusses separately the therapeutic options of acute colonic pseudo-obstruction, colonic volvulus, and malignant obstruction, providing an evidence-based orientation for clinical use.

Key Messages

Endoscopic decompression of colonic distension is an established therapy with high clinical success. The technique and its position in the therapy sequence differ depending on the medical condition, the trigger of the colonic distension, and the local expertise.

Does preoperative stent positioning in obstructive left sided colon cancer increase the risk of perineural invasion?

Colonic stenting as a bridge to surgery has been shown to be a safe and effective treatment for left-sided malignant colonic obstruction depending on local expertise. However, concerns still exist regarding its oncological safety. In particular, several reports showed an increased prevalence of perineural tumor invasion following stent placement. Since perineural invasion negatively affects oncological outcomes, the present study sought to evaluate this controversial association. We retrospectively reviewed 114 patients presenting with left-side obstructing colon cancer over a 10-year period. The relationship between perineural invasion and colonic stenting was analyzed using univariate and multivariate analyses. Perineural invasion was found to be strongly associated with pathological features, including TNM stage, (p < 0.001), poor differentiation (p = 0.002), vascular invasion (p < 0.001), lymphatic invasion (p < 0.001), whereas no significant association with preoperative stenting was observed (p = 0.918) after performing univariate analysis. In the multivariate model, only TNM stage III-IV (OR: 6.810, 95% CI 1.972-23.518, p = 0.002) and venous invasion (OR: 5.325, 95% CI 1.911-14.840, p = 0.001) were independently associated with perineural invasion. The results of this study suggest no association between preoperative colonic stenting and perineural invasion.