Colorectal stenting as a bridge to surgery reduces morbidity and mortality in left-sided malignant obstruction: a predictive risk score-based comparative study

Management of left-sided malignant colorectal obstructions with curative intent: a network meta-analysis

BACKGROUND

Several management options exist for colonic decompression in the setting of malignant large bowel obstruction, including oncologic resection, surgical diversion, and SEMS as a bridge-to-surgery. Consensus has yet to be reached on optimal treatment pathways. The aim of the present study was to perform a network meta-analysis comparing short-term postoperative morbidity and long-term oncologic outcomes between oncologic resection, surgical diversion, and self-expanding metal stents (SEMS) in left-sided malignant colorectal obstruction with curative intent.

METHODS

Medline, Embase, and CENTRAL were systematically searched. Articles were included if they compared two or more of the following in patients presenting with curative left-sided malignant colorectal obstruction: (1) emergent oncologic resection; (2) surgical diversion; and/or (3) SEMS. The primary outcome was overall 90-day postoperative morbidity. Pairwise meta-analyses were performed with inverse variance random effects. Random-effect Bayesian network meta-analysis was performed.

RESULTS

From 1277 citations, 53 studies with 9493 patients undergoing urgent oncologic resection, 1273 patients undergoing surgical diversion, and 2548 patients undergoing SEMS were included. Network meta-analysis demonstrated a significant improvement in 90-day postoperative morbidity in patients undergoing SEMS compared to urgent oncologic resection (OR0.34, 95%CrI0.01-0.98). Insufficient RCT data pertaining to overall survival (OS) precluded network meta-analysis. Pairwise meta-analysis demonstrated decreased five-year OS for patients undergoing urgent oncologic resection compared to surgical diversion (OR0.44, 95%CI0.28-0.71, p < 0.01).

CONCLUSIONS

Bridge-to-surgery interventions may offer short- and long-term benefits compared to urgent oncologic resection for malignant colorectal obstruction and should be increasingly considered in this patient population. Further prospective study comparing surgical diversion and SEMS is needed.

Definition of large bowel obstruction by primary colorectal cancer: A systematic review

AIM

Controversies on therapeutic strategy for large bowel obstruction by primary colorectal cancer mainly concern acute conditions, being essentially different from subacute obstruction. Clearly defining acute obstruction is important for design and interpretation of studies as well as for guidelines and daily practice. This systematic review aimed to evaluate definitions of obstruction by colorectal cancer in prospective studies.

METHOD

A systematic search was performed in PubMed, Embase and the Cochrane Library. Eligibility criteria included randomized or prospective observational design, publication between 2000 and 2019, and the inclusion of patients with an obstruction caused by colorectal cancer. Provided definitions of obstruction were extracted with assessment of common elements.

RESULTS

A total of 16 randomized controlled trials (RCTs) and 99 prospective observational studies were included. Obstruction was specified as acute in 28 studies, complete/emergency in five, (sub)acute or similar terms in four and unspecified in 78. Five of 16 RCTs (31%) and 37 of 99 cohort studies (37%) provided a definition. The definitions included any combination of clinical symptoms, physical signs, endoscopic features and radiological imaging findings in 25 studies. The definition was only based on clinical symptoms in 11 and radiological imaging in six studies. Definitions included a radiological component in 100% of evaluable RCTs (5/5) vs. 54% of prospective observational studies (20/37, P = 0.07).

CONCLUSION

In this systematic review, the majority of prospective studies did not define obstruction by colorectal cancer and its urgency, whereas provided definitions varied hugely. Radiological confirmation seems to be an essential component in defining acute obstruction.

Bowel obstruction: a narrative review for all physicians

Small and large bowel obstructions are responsible for approximately 15% of hospital admissions for acute abdominal pain in the USA and ~ 20% of cases needing acute surgical care. Starting from the analysis of a common clinical problem, we want to guide primary care physicians in the initial management of a patient presenting with acute abdominal pain associated with intestinal obstruction.

Long-Term Oncological Outcomes of Endoscopic Stenting as a Bridge to Surgery Versus Emergency Surgery for Malignant Colorectal Obstruction: A Comparative Study

AIM

With consideration of the theoretical link between the stent insertion and the increased risk of tumor cells spillaged, which may lead to distant metastases, there is a concern about long-term clinical outcomes after the usage of self-expanding metallic stents (SEMS) as a "bridge to surgery" in the malignant colorectal obstruction (MCO) treatment. This cohort study aimed to compare the long-term oncological outcomes of SEMS as a bridge to surgery (SEMS group) with those of emergency surgery (ES group) for MCO.

METHODS

Twenty-seven patients who underwent semielective curative resection after endoscopic SEMS insertion were included from October 2007 to December 2012 in the SEMS group were compared with 33 patients who underwent emergency curative surgery for MCO during the same period in the ES group. The clinical pathologic characteristics and the overall survival (OS) rate were compared between the two groups.

RESULTS

There were no significant differences in demographics, tumor stage, location, and histology between the SEMS and ES groups. The median OS times were 37 months for the SEMS group and 23 months for the ES group. The proportions of patients who received postoperative adjuvant chemotherapy were comparable (SEMS group versus ES group, 70.4% versus 45.5%; P = .138). There were no significant differences in terms of the long-term oncological outcome between two groups in the 3-year OS rate (55.6% versus 39.4%; P = .2119) and the 5-year OS rate (48.1% versus 36.4%; P = .3570).

CONCLUSIONS

Long-term oncological outcomes of the SEMS group were comparable to those of the ES group.

Outcome of bridge to surgery stenting for obstructive left colon cancer

BACKGROUND

The aim of our study was to compare short- and long-term outcomes of stent insertion followed by surgery with those of emergency surgery for left colon malignant obstructions.

METHODS

The medical records of patients who received curative resection due to obstructive primary left colon cancer and who were diagnosed with stage II or III from January 2004 to December 2010 in six hospitals affiliated with The Catholic University of Korea were reviewed. One hundred and twelve patients in self-expandable metallic stent (SEMS) group were matched to 56 patients in the emergency surgery (ES) group using propensity score matching method. Overall survival (OS) and disease-free survival (DFS) were compared between the groups. Perioperative outcomes and pathologic results were also compared.

RESULTS

Baseline characteristics were comparable between the two groups after matching. The analysis of perioperative outcomes showed short-term advantages of stent insertion. Patients in the SEMS group were more likely (87.5 versus 75.0%, P = 0.049) to have a distal resection margin >5 cm. Harvesting ≥12 lymph nodes were more frequent (89.3 versus 71.4%, P = 0.007) in the SEMS group. Five-year DFS was 69.5% in the SEMS group and 73.1% in the ES group (P = 0.464). Five-year OS was not different between the groups (79.7 versus 77.7%, P = 0.989).

CONCLUSIONS

SEMS can be a reasonable therapeutic option for malignant obstruction in patients with left colon cancer until definitive conclusion about the long-term survival effect of SEMS is made from further large-scale prospective randomized trials.

Comparative study of postoperative complications in patients with and without an obstruction who had left-sided colorectal cancer and underwent a single-stage operation after mechanical bowel preparation

Purpose

The purpose of this study is to compare postoperative complications for single-stage surgery after mechanical bowel preparation in patients who experienced obstruction and those who did not.

Methods

From 2000 to 2011, 1,224 patients underwent a single-stage operation for left colorectal cancer after bowel preparation. Nonobstruction (NOB) and obstruction (OB) colorectal cancer patients were 1,053 (86.0%) and 171 (14.0%), respectively. Postoperative morbidity and mortality were compared between groups.

Results

The OB group had poor preoperative conditions (age, white blood cell, hemoglobin, albumin level, and advanced tumor stage) compared with the NOB group (P < 0.05). Mean on-table lavage time for the OB group was 17.5 minutes (range, 14-60 minutes). Mean operation time for the OB group was statistically longer than that of the NOB group (OB: 210 minutes; range, 120-480 minutes vs. NOB: 180 minutes; range, 60-420 minutes; P < 0.001). Overall morbidity was similar between groups (NOB: 19.7% vs. OB: 23.4%, P = 0.259). Major morbidity was more common in the OB group than in the NOB group, but the difference was without significance (OB: 11.7% vs. NOB: 7.6%, P = 0.070). Postoperative death occurred in 16 patients (1.3%), and death in the OB group (n = 7) was significantly higher than it was in the NOB group (n = 9) (4.1% vs. 0.9%, P = 0.001). Twelve patients had surgical complications, which were the leading cause of postoperative death: postoperative bleeding in five patients and leakage in seven patients.

Conclusion

Postoperative morbidity for a single-stage operation for obstructive left colorectal cancer is comparable to that for NOB, regardless of poor conditions of the patient.

Colorectal stenting: An advanced approach to malignant colorectal obstruction

Some colorectal cancer (CRC) patients present symptoms of bowel obstruction, which is considered a surgical emergency. Because of poor medical condition and high incidence of post-surgical complications, there has been increasing use of self-expanding metal stents (SEMS) for the purpose of palliation or as a bridge to surgery with some benefits, including shorter hospital stays, lower rates of adverse events, and one-stage surgery. However, with increasing survival of CRC patients, there have been controversial data on clinical outcomes and complications, compared between SEMS use and surgery for treatment of malignant bowel obstruction. We review recent clinical data on clinical outcomes of SEMS use compared to surgery, including complications.

Perforation in colorectal stenting: a meta-analysis and a search for risk factors

BACKGROUND

Recent studies suggest that there is a substantial risk of perforation after colorectal stent placement.

OBJECTIVE

To identify risk factors for perforation from colonic stenting.

DESIGN

A meta-analysis of 86 studies published between 2005 and 2011.

SETTING

Multicenter review.

PATIENTS

All patients who underwent colorectal stent placement.

INTERVENTION

Colorectal stent placement.

MAIN OUTCOME MEASUREMENTS

The occurrence of perforation with subgroup analyses for stent design, stricture etiology, stricture dilation, and concomitant chemotherapy, including the use of bevacizumab.

RESULTS

A total of 4086 patients underwent colorectal stent placement; perforation occurred in 207. Meta-analysis revealed an overall perforation rate of 7.4%. Of the 9 most frequently used stent types, the WallFlex, the Comvi, and the Niti-S D-type had a higher perforation rate (>10%). A lower perforation rate (<5%) was found for the Hanarostent and the Niti-S covered stent. Stenting benign strictures was associated with a significantly increased perforation rate of 18.4% compared with 7.5% for malignant strictures. Dilation did not increase the risk of perforation: 8.5% versus 8.5% without dilation. The subgroup of post-stent placement dilation had a significantly increased perforation risk of 20.4%. With a perforation rate of 12.5%, bevacizumab-based therapy was identified as a risk factor for perforation, whereas the risk for chemotherapy without bevacizumab was 7.0% and not increased compared with the group without concomitant therapies during stent therapy (9.0%).

LIMITATIONS

Heterogeneity; a considerable proportion of data is unavailable for subgroup analysis.

CONCLUSIONS

The perforation rate of colonic stenting is 7.4%. Stent design, benign etiology, and bevacizumab were identified as risk factors for perforation. Intraprocedural stricture dilation and concomitant chemotherapy were not associated with an increased risk of perforation.

Surgical emergencies in oncology

An oncologic emergency is defined as an acute, potentially life threatening condition in a cancer patient that has developed as a result of the malignant disease or its treatment. Many oncologic emergencies are signs of advanced, end-stage malignant disease. Oncologic emergencies can be divided into medical or surgical. The literature was reviewed to construct a summary of potential surgical emergencies in oncology that any surgeon can be confronted with in daily practice, and to offer insight into the current approach for these wide ranged emergencies. Cancer patients can experience symptoms of obstruction of different structures and various causes. Obstruction of the gastrointestinal tract is the most frequent condition seen in surgical practice. Further surgical emergencies include infections due to immune deficiency, perforation of the gastrointestinal tract, bleeding events, and pathological fractures. For the institution of the appropriate treatment for any emergency, it is important to determine the underlying cause, since emergencies can be either benign or malignant of origin. Some emergencies are well managed with conservative or non-invasive treatment, whereas others require emergency surgery. The patient's performance status, cancer stage and prognosis, type and severity of the emergency, and the patient's wishes regarding invasiveness of treatment are essential during the decision making process for optimal management.

Long-term oncologic outcomes of endoscopic stenting as a bridge to surgery for malignant colonic obstruction: comparison with emergency surgery

BACKGROUND

Self-expandable metallic stents (SEMS) are now regarded as an effective and safe intervention for malignant colorectal obstruction (MCO). However, manipulation of the tumor might lead to the spillage of tumor cells and result in distant metastases. We aimed to compare the long-term oncologic outcomes of SEMS as a bridge to surgery with those of emergency surgery for MCO.

METHODS

Between June 2005 and December 2011, 60 patients who underwent elective curative resection after endoscopic SEMS insertion were included in the "SEMS group". The SEMS group was matched to 180 patients who underwent emergency curative surgery for MCO during the same period ["Emergency surgery (ES) group"]. The clinicopathologic characteristics, recurrence-free survival (RFS), and overall survival (OS) were compared between the two groups.

RESULTS

There were no significant differences in demographics, tumor stage, location, and histology between the SEMS group and the ES group. The median follow-up times were 41.4 months (IQR, 22.2-60.0 months) for the SEMS group and 45.0 months (IQR, 20.9-68.1 months) for the ES group. The proportions of patients who received postoperative adjuvant chemotherapy were comparable (SEMS group vs. ES group, 68.3 % vs. 77.8 %; P = 0.210). The long-term prognosis did not significantly differ between two groups in either the 5-year RFS rate (79.6 % vs. 70.2 %; P = 0.218) or the 5-year OS rate (97.8 % vs. 94.3 %; P = 0.469).

CONCLUSIONS

Long-term oncologic outcomes of SEMS insertion as a bridge to surgery were comparable to those of primary curative surgery.

A meta-analysis of endoscopic stenting as bridge to surgery versus emergency surgery for left-sided colorectal cancer obstruction

The best approach to resolve colonic obstruction in patients with left-sided colon cancer is not established. In this meta-analysis the efficacy of stenting as bridge-to-surgery was compared to emergency surgery for the management of left-sided colonic obstruction. Fourteen studies (randomized and non controlled studies) were identified, including 405 patients in the stent group and 471 in the emergency group. The difference between proportions was evaluated as effect size (ESi). There was large heterogeneity among the studies. Stenting offered advantages over emergency surgery in terms of increase in primary anastomosis (ES=25.1%, p<0.001), successful primary anastomosis (ES=23.7%, p<0.001), reduction of stoma creation (ES=-27.1%, p=0.03), infections (ES=-7.9%, p=0.006) and other morbidities (ES=-13.4%, p<0.001). The interventions were similar in regards to length of hospitalization, preoperative mortality and long-term survival.