Long-term success of colonic stent insertion is influenced by indication but not by length of stent or site of obstruction

Colon stenting as a bridge to surgery in obstructive colorectal cancer management

Colonic stent placement is a commonly used bridging strategy for surgery in patients with obstructive colorectal cancer. The procedure involves the placement of a self-expandable metallic stent (SEMS) across the obstructive lesion to restore intestinal patency and alleviate the symptoms of obstruction. By allowing patients to receive surgery in a planned and staged manner with time for preoperative optimization and bowel preparation, stent placement may reduce the need for emergency surgery, which is associated with higher complication rates and poorer outcomes. This review focuses on the role of colon stenting as a bridge to surgery in the management of obstructive colorectal cancer. SEMS as a bridge to surgery for left-sided colon cancer has been demonstrated to be particularly useful; however, further research is needed for its application in cases of right-sided colon cancer. Colon stent placement also has limitations and potential complications including stent migration, re-obstruction, and perforation. However, the timing of curative surgery after SEMS placement remains inconclusive. Considering the literature to date, performing surgery at an interval of approximately 2 weeks is considered appropriate. Therefore, colonic stent placement may be an effective strategy as a bridge to surgery in patients with obstructive colorectal cancer.

Short-term outcomes of stents in obstructive rectal cancer: A systematic review and meta-analysis

BACKGROUND

With acute obstruction due to rectal or recto-sigmoid cancer, the safety and success of deploying self-expandable metal stents has been controversial. The aim of this systematic review was to synthesize the existing evidence on the outcomes and complication rates of stent placement in these patients.

METHODS

We performed a literature search of PubMed by using appropriate keywords, and manual reference screening of included articles was done. The article screening, data extraction, and quality assessment was done by four independent reviewers. A meta analyses was performed for the main outcome measures: technical and clinical success and complication rates.

RESULTS

We identified 962 articles in the search. After applying inclusion and exclusion criteria, we included 32 articles in the meta-analysis. The pooled technical success rate across 26 studies that reported it was 97% [95% confidence interval (CI): 95%-99%] without evidence of significant heterogeneity (I² = 0.0%, P = 0.84), and the clinical success rate across 26 studies that reported it was 69% (95% CI: 58%-79%) with evidence of significant heterogeneity (I² = 81.7%, P < 0.001). The pooled overall complication rate across the 32 studies was 28% (95% CI: 20%-37%) with evidence of significant heterogeneity (I² = 79.3%, P < 0.001).

CONCLUSION

The use of rectal stents in obstructing rectal or recto-sigmoid tumors seems to be technically feasible. A high rate of technical success, however, does not always translate into clinical success. A considerable complication rate is associated with this approach. Randomized controlled trials are needed to compare the outcomes of rectal stent placement with those of surgery.

Colonic Stenting in the Emergency Setting

Nowadays, colorectal cancer (CRC) is the third most frequent cancer, and about a third of patients with CRC presents themselves with symptoms of large bowel obstruction. Historically, surgical resection was the treatment of choice for colonic obstruction, but this kind of approach is burdened by a high risk of postoperative morbidity and mortality. In recent times, the use of a colonic stent has been proposed to overcome the obstruction and transform an emergency surgical case into an elective one to avoid emergency surgery complications. Endoscopic stenting is the first-line treatment option in the palliative management of colonic obstruction, and there is sufficient scientific evidence to support this approach. However, endoscopic stent used as a bridge to surgery is not yet widely adopted because the concern was raised about the long-term survival and cancer safety of this approach. The recent scientific evidence has shown that this approach improves the short-term outcomes, such as postoperative complications and the stoma rate, without differences in long-term outcomes compared to emergency surgery. Therefore, the European Society for Gastrointestinal Endoscopy in 2020 has reconsidered stenting as a bridge to surgery as a valid alternative to emergency surgery.

Efficacy of uncovered colonic stents for extrinsic versus intrinsic malignant large bowel obstruction

BACKGROUND

Previous studies evaluating self-expandable metal stents (SEMS) for management of malignant extrinsic colon obstruction have yielded conflicting results. We evaluated the efficacy of uncovered SEMS for extrinsic colon malignancy (ECM) versus intrinsic colon malignancy (ICM).

METHODS

Retrospective review of all patients referred for colonic SEMS at a tertiary cancer center between 2007 and 2018 was performed. Primary outcome measures were technical success, clinical success, intervention rate, and overall survival.

RESULTS

138 patients with ECM and 119 patients with ICM underwent attempted stent placement. The rectum and/or sigmoid colon was the most common stricture site. Technical success was lower in the ECM group [86% vs 96% (p = .009)]. Clinical success was lower in the ECM group both at 7 days [82% vs 95% (p = .004)] and at 90 days [60% vs 86% (p < .001)]. Subsequent intervention was required more frequently [44% vs 35%; p = .23] and earlier [median 9 vs 132 days; p < .001] in the ECM group. Median overall survival in the ECM group was 92 vs 167 days. Among predictive variables analyzed, the ECM group had a higher frequency of peritoneal metastasis (87% vs 32%; p < .001), multifocal strictures with requirement for multiple stents (20% vs 6%; p = .002), sharp angulated strictures (39% vs 25%; p = .04) , and radiation therapy (21% vs 10%; p = .02).

CONCLUSIONS

Colonic SEMS for ECM is associated with lower technical and clinical success with earlier intervention rates compared with ICM. Our findings can be used to better inform patients and referring providers as well as guide new stent design to enhance efficacy in this population.

Endoscopic Management of Malignant Colonic Obstruction

Advanced colorectal cancer can cause acute colonic obstruction, which is a life-threatening condition that requires emergency bowel decompression. Malignant colonic obstruction has traditionally been treated using emergency surgery, including primary resection or stoma formation. However, relatively high rates of complications, such as anastomosis site leakage, have been considered as major concerns for emergency surgery. Endoscopic management of malignant colonic obstruction using a self-expandable metal stent (SEMS) was introduced 20 years ago and it has been used as a first-line palliative treatment. However, endoscopic treatment of malignant colonic obstruction using SEMSs as a bridge to surgery remains controversial owing to short-term complications and longterm oncological outcomes. In this review, the current status of and recommendations for endoscopic management using SEMSs for malignant colonic obstruction will be discussed.

Endoscopic stenting of malignant, benign and iatrogenic colorectal disorders: a primer for radiologists

In recent years, endoscopic placement of intraluminal stents is increasingly used to manage a widening range of colorectal disorders. Self-expanding metal stents represent an established alternative to surgery for the palliation of unresectable carcinomas and currently allow a "bridge-to-surgery" strategy to relieve large bowel obstruction and optimise the patients' clinical conditions before elective oncologic resection. Additionally, intraluminal stents represent an appealing option to manage obstructing extracolonic tumours and selected patients with benign conditions such as refractory anastomotic strictures and post-surgical leaks.This educational paper reviews the technical features and current indications of colorectal stenting and presents the expected and abnormal radiographic, CT and MRI appearances observed during the endoscopic management of malignant, benign and iatrogenic colonic disorders with stents. The aim is to provide radiologists with a thorough familiarity with stent-related issues, which is crucial for appropriate reconstruction of focused CT images, correct interpretation of early post-procedural studies and elucidation of stent-related complications such as misplacement, haemorrhage, perforation, migration and re-obstruction.

Self-Expanding Metallic Stents for the Management of Emergency Malignant Large Bowel Obstruction: a Systematic Review

OBJECTIVES

This paper evaluates the safety and effectiveness of self-expanding metallic stents (SEMS) for the management of emergency malignant colorectal obstruction in patients otherwise requiring multi-stage surgery. No systematic review has been conducted comparing SEMS to only multi-stage surgery.

METHODS

Bibliographic databases, including Cochrane, PubMed, EMBASE, and CINAHL, were searched in September 2011 and repeated in November 2013. A pre-determined protocol outlined the study inclusion and appraisal.

RESULTS

Forty articles were included, seven compared SEMS to multi-stage surgery. Included studies were of low to moderate quality. Bowel perforation was the most severe stent-related complication, while tumor- and stent-related events occurred most frequently. No significant differences in rates of obstruction relief were reported between treatments, and results regarding relative quality of life were inconclusive. SEMS recipients progressed to elective surgery sooner and required shorter post-procedural hospital stays, but commonly required re-intervention. SEMS provided enduring palliative relief of obstruction, with comparable survival longevity between treatments. Conclusion: SEMS placement is a viable alternative to multi-stage surgery, providing patients with benefits as a bridge-to-surgery and relief of obstruction in a palliative context, with minimal differences in clinical success and safety compared to multi-stage surgery.

Stents for colorectal obstruction: Past, present, and future

Since the development of uncovered self-expanding metal stents (SEMS) in the 1990s, endoscopic stents have evolved dramatically. Application of new materials and new designs has expanded the indications for enteral SEMS. At present, enteral stents are considered the first-line modality for palliative care, and numerous types of enteral stents are under development for extended clinical usage, beyond a merely palliative purpose. Herein, we will discuss the current status and the future development of lower enteral stents.

A novel anchoring system for colonic stents: a pilot in vivo study in a porcine model

BACKGROUND

Colorectal stents have a proven role in colorectal cancer as palliative care or a bridge to surgery. However, their efficacy and anchoring to the tissue varies according to stent design with stent migration rates up to 50 %. We present preliminary in vivo results of a new end-luminal anchoring system for stent fixation to the rectal canal. The aim was to assess the efficacy and safety of the stent using the anchoring system while subjecting the device to daily abdominal pressures related to daily activities in a porcine animal model.

METHODS

Ex vivo anatomical and physical studies were performed to improve the system's structure and safety. Four female pigs were followed for the acute and chronic (16 weeks) period. Two animals were euthanized and underwent en-bloc pelvic visceral excision and histopathological examination. Device fixation time, animal behavior, device patency, anoscopic examination and histopathological features were assessed.

RESULTS

Mean anchoring time was 13.83 weeks (standard error ± 1.38 weeks). One of the animals experienced early device expulsion with no complications. No obstruction was noted in any of the animals. Macroscopic examination revealed mild focal submucosal scarring in one animal and a normal examination in the other. Hematoxylin and eosin staining revealed mucosal ulceration and mixed inflammatory cell infiltrate, with no signs of granulomata, foreign body giant cell reaction or microabscess formation.

CONCLUSIONS

A novel fixation device designed for long-term intrarectal implantation was well tolerated and maintained anal canal patency without migration. Larger studies are needed before its implementation in humans.

Evidence-based recommendations on colorectal stenting: a report from the stent study group of the korean society of gastrointestinal endoscopy

Recently, placement of self-expandable metallic stents has been used for the treatment of colorectal obstruction. As domestic awareness of colorectal cancer has increased, the number of colorectal stenting procedures performed has also increased. We aimed to provide evidence-based recommendations for colorectal stenting to aid gastroenterologists in making informed decisions regarding the management of patients who present with colorectal obstruction. The working group consisted of eight gastroenterologists who actively practice and conduct research in the field of colorectal stenting and are the members of the Stent Study Group of the Korean Society of Gastrointestinal Endoscopy. A literature search was conducted using the PubMed, Embase, KoreaMed, and the Cochrane Library databases to identify relevant articles published between January 2001 and June 2012. Based on the modified Delphi process, 10 recommendation statements regarding indications, usefulness, methodology and complications of colorectal stenting, and alternative treatments for malignant colorectal obstruction were determined. The contents will be widely distributed, and periodically revised to reflect the latest knowledge. These evidence-based recommendations for colorectal stenting will provide gastroenterologists and patients with appropriate and balanced information, and will improve the quality of care.

Principles of surgical oncology in the elderly

Elderly patients constitute the largest group in oncologic medical practice, despite the fact that in solid cancers treated operatively, many patients are denied standard therapies and where such decision making is based solely on age. The “natural” assumptions that we have are often misleading; namely, that the elderly cannot tolerate complex or difficult procedures, chemotherapy, or radiation schedules; that their overall predictable medical health determines survival (and not the malignancy); or that older patients typically have less aggressive tumors. Clearly, patient selection and a comprehensive geriatric assessment is key where well-selected cases have the same cancer-specific survival as younger cohorts in a range of tumors as outlined including upper and lower gastrointestinal malignancy, head and neck cancer, and breast cancer. The assessment of patient fitness for surgery and adjuvant therapies is therefore critical to outcomes, where studies have clearly shown that fit older patients experience the same benefits and toxicities of chemotherapy as do younger patients and that when normalized for preexisting medical conditions,that older patients tolerate major operative procedures designed with curative oncological intent. At present, our problem is the lack of true evidence-based medicine specifically designed with age in mind, which effectively limits surgical decision making in disease-based strategies. This can only be achieved by the utilization of more standardized, comprehensive geriatric assessments to identify vulnerable older patients, aggressive pre-habilitation with amelioration of vulnerability causation, improvement of patient-centered longitudinal outcomes, and an improved surgical and medical understanding of relatively subtle decreases in organ functioning, social support mechanisms and impairments of health-related quality of life as a feature specifically of advanced age.