Uncovered versus covered stent in management of large bowel obstruction due to colorectal malignancy: a systematic review and meta-analysis

Management of obstructed colorectal carcinoma in an emergency setting: An update

Colorectal carcinoma is common, particularly on the left side. In 20% of patients, obstruction and ileus may be the first clinical manifestations of a carcinoma that has advanced (stage II, III or even IV). Diagnosis is based on clinical presentation, plain abdominal radiogram, computed tomography (CT), CT colonography and positron emission tomography/CT. The best management strategy in terms of short-term operative or interventional and long-term oncological outcomes remains unknown. For the most common left-sided obstruction, the first choice should be either emergency surgery or endoscopic decompression by self-expendable metal stents or tubes. The operative plan should be either one-stage or two-stage resection. One-stage resection with on-table bowel decompression and irrigation can be accompanied or not accompanied by proximal defunctioning stoma (colostomy or ileostomy). Primary anastomosis is more convenient but has increased risks of anastomotic leakage and morbidity. Two-stage resection (Hartmann's procedure) is safer and the most widely used despite temporally affecting quality of life. Damage control surgery in high-risk frail patients is less frequently performed since it can be successfully substituted with endoscopic stenting or tubing. For the less common right-sided obstruction, one-stage surgical resection is more beneficial than endoscopic decompression. The role of minimally invasive surgery (laparoscopic or robotic) is a subject of debate. Emergency laparoscopic-assisted management is advantageous to some extent but requires much expertise due to inherent difficulties in dissecting the distended colon and the risk of rupture and subsequent septic complications. The decompressing stent as a bridge to elective surgery more substantially decreases the risks of morbidity and mortality than emergency surgery for decompression and has equivalent medium-term overall survival and disease-free survival rates. Its combination with neoadjuvant chemotherapy or radiation may have a positive effect on long-term oncological outcomes. Management plans are crucial and must be individualized to better fit each case.

Malignant Acute Colonic Obstruction: Multidisciplinary Approach for Endoscopic Management

Patients presenting with acute colonic obstruction are usually evaluated in the emergency department and multiple specialties are involved in the patients' management. Pre-treatment evaluation is essential in order to establish the correct endoscopic indication for stent implantation. Contrast-enhanced imaging could allow the exclusion of benign causes of colonic obstruction and evaluation of the length of malignant stricture. Endoscopic stenting is the gold standard of treatment for palliative indications whereas there are still concerns about its use as a bridge to surgery. Different meta-analyses showed that stenting as a bridge to surgery improves short-term surgical outcomes but has no role in improving long-term outcomes. Multidisciplinary evaluation is also essential in patients that may be started on or are currently receiving antiangiogenic agents because endoscopic stenting may increase the risk of perforation. Evidence in the literature is weak and based on retrospective data. Here we report on how to correctly evaluate a patient with acute colonic malignant obstruction in collaboration with other essential specialists including a radiologist, surgeon and oncologist, and how to optimize the technique of endoscopic stenting.

Best Practices in Esophageal, Gastroduodenal, and Colonic Stenting

Endoscopic stenting is an area of endoscopy that has witnessed noteworthy advancements over the last decade, resulting in evolving clinical practices among gastroenterologists around the world. Indications for endoscopic stenting have progressively expanded, becoming a frequent part of the management algorithm for various benign and malignant conditions of the gastrointestinal tract, from esophagus to rectum. In addition to expanded indications, continuous technological enhancements and development of novel endoscopic stents have resulted in an increased success of these approaches and, in some cases, allowed new applications. This review aimed to summarize best practices in esophageal, gastroduodenal, and colonic stenting.

Endoscopic stent placement with laparoscopic stent fixation in a patient with obstruction at a gastrojejunostomy anastomosis site

BACKGROUND

Palliative endoscopic stent placement may be considered in patients with malignant gastrointestinal obstruction. Stent migration is a potential complication, particularly for those placed at a surgical anastomosis or across a stricture caused by extra-alimentary tract factors. We report a patient with left renal pelvis cancer and gastrojejunostomy obstruction who underwent endoscopic stent placement and laparoscopic stent fixation.

CASE PRESENTATION

A 60-year-old male with peritoneal dissemination of a left renal pelvis cancer was admitted for treatment of upper gastrointestinal obstruction. A laparoscopic gastrojejunostomy had been previously performed for cancer invasion of the duodenum. Imaging showed gastroduodenal dilation and impaired passage of contrast medium through the efferent loop of the gastrojejunostomy. Gastrojejunostomy anastomosis site obstruction due to dissemination of left renal pelvis cancer was diagnosed. Conservative treatment failed and endoscopic stent placement with laparoscopic stent fixation was performed. After surgery, the patient was able to tolerate oral intake and he was discharged without complications. The patient gained weight and was able to resume chemotherapy, indicating the procedure was effective.

CONCLUSIONS

Endoscopic stent placement with laparoscopic stent fixation for malignant upper gastrointestinal obstruction appears effective in patients with a high risk of stent migration.

Acute left-sided malignant colonic obstruction: Is there a role for endoscopic stenting?

The therapy of left-sided malignant colonic obstruction continues to be one of the largest problems in clinical practice. Numerous studies on colonic stenting for neoplastic colonic obstruction have been reported in the last decades. Thereby the role of self-expandable metal stents (SEMS) in the treatment of malignant colonic obstruction has become better defined. However, numerous prospective and retrospective investigations have highlighted serious concerns about a possible worse outcome after endoscopic colorectal stenting as a bridge to surgery, particularly in case of perforation. This review analyzes the most recent evidence in order to highlight pros and cons of SEMS placement in left-sided malignant colonic obstruction.

Oncologic safety of colonic stenting as a bridge to surgery in left-sided malignant colonic obstruction: Current evidence and prospects

Approximately 7%-29% of patients with colorectal cancer present with colonic obstruction. The concept of self-expandable metal stent (SEMS) insertion as a bridge to surgery (BTS) is appealing. However, concerns on colonic stenting possibly impairing oncologic outcomes have been raised. This study aimed to review current evidence on the short- and long-term oncologic outcomes of SEMS insertion as BTS for left-sided malignant colonic obstruction. For short-term outcomes, colonic stenting facilitates a laparoscopic approach, increases the likelihood of primary anastomosis without a stoma, and may decrease postoperative morbidity. However, SEMS-related perforation also increases local recurrence and impairs overall survival. Moreover, colonic stenting may cause negative oncologic outcomes even without perforation. SEMS can induce shear forces on the tumor, leading to increased circulating cancer cells and aggressive pathological characteristics, including perineural and lymphovascular invasion. The conflicting evidence has led to discordant guidelines. Well-designed collaborative studies that integrate both oncologic outcomes and data on basic research (e.g., alteration of circulating tumors) are needed to clarify the actual benefit of colonic stenting as BTS.

Are Thyroid Functions Affected in Multisystem Inflammatory Syndrome in Children?

OBJECTIVE

Multisystem inflammatory syndrome in children (MIS-C), associated with Coronavirus disease-2019, is defined as the presence of documented fever, inflammation, and at least two signs of multisystem involvement and lack of an alternative microbial diagnosis in children who have recent or current Severe acute respiratory syndrome-Coronavirus-2 infection or exposure. In this study, we evaluated thyroid function tests in pediatric cases with MIS-C in order to understand how the hypothalamus-pituitary-thyroid axis was affected and to examine the relationship between disease severity and thyroid function.

METHODS

This case-control study was conducted between January 2021 and September 2021. The patient group consisted of 36 MIS-C cases, the control group included 72 healthy children. Demographic features, clinical findings, inflammatory markers, thyroid function tests, and thyroid antibody levels in cases of MIS-C were recorded. Thyroid function tests were recorded in the healthy control group.

RESULTS

When MIS-C and healthy control groups were compared, free triiodothyronine (fT3) level was lower in MIS-C cases, while free thyroxine (fT4) level was found to be lower in the healthy group (p<0.001, p=0.001, respectively). Although the fT4 level was significantly lower in controls, no significant difference was found compared with the age-appropriate reference intervals (p=0.318). When MIS-C cases were stratified by intensive care requirement, fT3 levels were also lower in those admitted to intensive care and also in those who received steroid treatment (p=0.043, p<0.001, respectively).

CONCLUSION

Since the endocrine system critically coordinates and regulates important metabolic and biochemical pathways, investigation of endocrine function in MIS-C may be beneficial. These results show an association between low fT3 levels and both diagnosis of MIS-C and requirement for intensive care. Further studies are needed to predict the prognosis and develop a long-term follow-up management plan.

Clinical outcomes of palliative self-expandable metal stent placement in right- and left-sided malignant colon obstruction: A Honam Association for the Study of Intestinal Disease (HASID) multicenter study

Self-expandable metal stent (SEMS) placement is commonly used for palliation of left-sided malignant colorectal obstruction (MCO). However, right-sided MCO is usually treated surgically. Recent studies that compared palliative SEMS insertion and emergency surgery in right-sided MCOs have reported conflicting results. This study aimed to compare the effectiveness of palliative SEMS placement in left-sided MCOs and right-sided MCOs and to investigate the predictive factors for clinical success and risk factors for complications. Data from 469 patients who underwent palliative SEMS placement for MCO at 6 hospitals in the Honam province of South Korea between 2009 and 2018 were reviewed. Among them, 69 patients with right-sided MCO and 400 patients with left-sided MCO who underwent SEMS placement for palliative purposes were enrolled. Clinical success, overall survival, complications, and predictive factors for clinical success and risk factors for complications were included as the main outcome measures. The clinical success rates were 97.1% (65/67) in right-sided MCO patients and 88.2% (353/400) in left-sided MCO patients. Complications including stent migration, tumor ingrowth, outgrowth, perforation, bacteremia/fever, and bleeding occurred in 10.1% (7/69) of right-sided MCO patients and 19.9% (79/400) of left-sided MCO patients. The mean overall survival of right-sided MCO was 28.02 months and 18.23 months for left-sided MCO. In multivariate logistic regression analysis, T3 stage tumors and the use of uncovered stents were significant factors for the clinical success of SEMS. The use of covered stents and performance status score of 0 to 2 were independent significant risk factors for complications. Palliative SEMS placement in right-sided MCO showed better clinical success rates than left-sided MCO. The use of uncovered stents is recommended for higher clinical success rates and lower complication rates.

Intestinal stents: Structure, functionalization and advanced engineering innovation

Intestinal stents are a palliative treatment option that solves many shortcomings of traditional surgeries for cancer-induced intestinal obstructions. The present review provides an overview of the incidence, clinical manifestations and limitations in the treatment of intestinal cancers. The paper also discusses material property requirements, indications, complications and the future of stent-assisted therapy. The advantages and disadvantages of different materials and processing techniques for intestinal stents are reviewed along with new stent treatment combinations for colorectal cancer. Challenges that require further cooperative studies are also detailed. The future development of intestinal stents will depend on innovation in material designs as well as the utilization of multi-functional strategies and innovative engineering solutions.

Detection methods of synchronous colorectal lesions in proximal colon for patients with obstructive colorectal cancer: a literature review

INTRODUCTION

Colorectal cancer holds a high morbidity and mortality rate. As a common method for colorectal cancer detection, colonoscopy has difficulty in passing through the malignant stenosis in patients with obstructive colorectal cancer, which results in incomplete detection and missed diagnosis. The missed synchronous lesions increase the risk of metachronous cancer. Therefore, detecting proximal synchronous lesions in patients with obstructive colorectal cancer should be appreciated before operation.

AREA COVERED

This review evaluates related literature, aiming at providing clinicians with more ideas and attention for detecting proximal synchronous lesions in patients with obstructive colorectal cancer.

EXPERT OPINION

In patients with obstructive colorectal cancer, missed diagnosis of lesions proximal to the obstruction may lead to metachronous colorectal cancer. Except for preoperative colonoscopy which is difficult to pass through malignant stenosis, other methods that can evaluate proximal colon segment are critical. This article introduced several preoperative, intraoperative and postoperative measures for synchronous lesions detection. The choice of methods should base on patients' conditions, aiming at a high diagnostic yield and low risk. Early detection and resection of synchronous lesions in the proximal section of malignant obstruction are expected to minimize the risk of metachronous colorectal cancer and even effect follow-up treatment strategy, which deserves the attention of clinicians.

Recent Updates in Gastrointestinal Stent Placement from the Esophagus to the Colon: A Radiological Perspective

Fluoroscopic-guided stent placement has become an advantageous treatment option for diverse gastrointestinal disorders. In addition to palliative stent placement in patients with inoperable cancers, stenting has gradually expanded to other conditions, including as a bridge to surgery, as well as in patients' benign lesions and anastomotic strictures or leaks. This narrative review describes the indications, efficacy and safety of stent placement from the esophagus to the colon, including current recommendations, recent updates, and novel stents.

Localized Photothermal Ablation Therapy of Obstructive Rectal Cancer Using a Nanofunctionalized Stent in a Mouse Model

The self-expanding metal stent (SEMS) is a versatile, palliative treatment method for unresectable, malignant, non-vascular strictures. Colorectal cancer (CRC) is one of the candidates for the application of the SEMS, in combination with the photothermal ablation (PTA) technique that enhances its therapeutic efficacy. The objective of this study was to investigate the efficacy of stent-mediated PTA therapy in an endoscopy-guided, orthotopic rectal cancer model. A total of 30 of 40 mice with the tumor size of grade 4 were included and were divided into three groups of 10 mice each. Group A underwent a gold nanoparticle (AuNP)-coated SEMS but no near-infrared (NIR) irradiation, group B received an uncoated control SEMS with NIR irradiation, and group C received a AuNP-coated SEMS and NIR irradiation together. Colonoscopy and in vivo imaging, immunohistochemical analysis, and quantitative reverse-transcription polymerase chain reaction of major tumor markers were performed. Stent placement and PTA were technically successful using colonoscopy. The tumor grade reduction after PTA is significant in group C, compared with groups A or B (p < 0.001). Molecular analysis validated this observation with a significantly reduced Mapk1 proliferation marker or increased Jnk expression. Histological analysis confirmed the localized PTA therapy using AuNP-coated SEMS profoundly ablated tumor outgrowth through the stent. Our results indicate that this novel strategy of localized PTA therapy could be a promising option for palliative treatment of CRC and to support prolonged stent patency with a decreased tumor volume.

AGA Clinical Practice Update on the Optimal Management of the Malignant Alimentary Tract Obstruction: Expert Review

BACKGROUND & AIMS

The purpose of this expert review is to describe the current methodologies available to manage malignant alimentary tract obstructions as well the evidence behind the various methods (including their efficacy and safety), indications, and appropriate timing of interventions.

METHODS

This is not a formal systematic review but is based on a review of the literature to provide best practice advice statements. No formal rating of the quality of evidence or strength of recommendation is carried out. BEST PRACTICE ADVICE 1: For all patients with alimentary tract obstruction, the decision about specific interventions should be made in a multidisciplinary setting including oncologists, surgeons, and endoscopists and take into account the characteristics of the obstruction, patient's expectations, prognosis, expected subsequent therapies, and functional status. BEST PRACTICE ADVICE 2: For patients who present with esophageal obstruction from esophageal cancer and who are potential candidates for resection or chemoradiation, clinicians should not routinely insert a self-expanding metal stent (SEMS) without multidisciplinary review because of high rates of stent migration, higher morbidity and mortality, and potentially lower R0 (microscopically negative margins) resection rates. BEST PRACTICE ADVICE 3: For patients who present with esophageal obstruction from esophageal cancer who are potential candidates for resection and who have concerns of malnutrition, clinicians may consider the use of enteral feeding tubes (via nasogastric or percutaneous route). Clinicians should be aware of the potential risk of abdominal wall tumor seeding as well as making subsequent gastric conduit formation difficult with percutaneous endoscopic gastrostomy placement. BEST PRACTICE ADVICE 4: For patients who present with esophageal obstruction from esophageal cancer who are not candidates for resection, clinicians should consider either SEMS insertion or brachytherapy as sole therapy or in combination. Clinicians should not consider the use of laser therapy or photodynamic therapy because of the lack of evidence of better outcomes and superior alternatives. BEST PRACTICE ADVICE 5: For patients with malignant esophageal obstruction who are undergoing SEMS placement, clinicians should use a fully covered or partially covered SEMS and not an uncovered SEMS, with consideration of a stent-anchoring/fixation method. BEST PRACTICE ADVICE 6: For patients with gastric outlet obstruction who have a life expectancy greater than 2 months, have good functional status, and who are surgically fit, surgical gastrojejunostomy should be considered. BEST PRACTICE ADVICE 7: For patients with gastric outlet obstruction who are undergoing surgical gastrojejunostomy, a laparoscopic approach is favored over an open approach because of lower blood loss and shorter hospital stay. BEST PRACTICE ADVICE 8: For patients with gastric outlet obstruction who are not candidates for gastrojejunostomy (surgical or endoscopic ultrasound-guided), clinicians should consider the insertion of an enteral stent. BEST PRACTICE ADVICE 9: Enteral stents should not be used in patients with multiple luminal obstructions or severely impaired gastric motility because of the limited benefit in these scenarios. Clinicians can consider placement of a venting gastrostomy in these patients. BEST PRACTICE ADVICE 10: Depending on the experience of the endoscopist, endoscopic ultrasound-guided gastrojejunostomy is an acceptable alternative to surgical gastrojejunostomy and enteral stent placement. Clinicians should be aware that there are currently no dedicated Food and Drug Administration-approved devices for endoscopic ultrasound-guided gastrojejunostomy. BEST PRACTICE ADVICE 11: For patients with malignant colonic obstruction who are candidates for resection, insertion of SEMS is a reasonable choice as a "bridge to surgery" to allow for one-stage, elective resection. BEST PRACTICE ADVICE 12: For patients with malignant colonic obstruction who are not candidates for resection, either SEMS placement or a diverting colostomy are reasonable choices depending on the patient's goals and functional status. BEST PRACTICE ADVICE 13: SEMS is a reasonable option for patients with proximal (or right-sided) malignant obstructions, both as a "bridge to surgery" and in the palliative setting. BEST PRACTICE ADVICE 14: SEMS placement is a reasonable alternative for patients with extracolonic malignancy who are not candidates for surgery, although their placement is more technically challenging, clinical success rates are more variable, and complications (including stent migration) are more frequent.

[Palliative endoscopy]

Endoscopy is the leading method in the diagnostics of gastrointestinal malignancies. With the increasing incidences of various tumor entities, a palliative treatment situation is already present in many patients despite an increasing number of screening strategies. Palliative endoscopy can make an essential contribution to alleviation of tumor-related symptoms, such as dysphagia, malnutrition, cholestasis, ileus and pain. Various approaches can be offered to safeguard the nutrition, e.g. percutaneous endoscopic gastrostomy (PEG) and percutaneous endoscopic jejunostomy (PEJ), for maintenance of the gastrointestinal passage (stents) and secretion drainage or to drain congested hollow organs. Furthermore, in cases of inaccessibility or impassability of stenoses due to tumors, endosonographically assisted punctures offer the possibility to guarantee new drainage options or continuities by stent placement. In all interventions possible contraindications and complications must be taken into account.

Comparison of different types of covered self-expandable metal stents for malignant colorectal obstruction

BACKGROUND

Stent migration is one of the main drawbacks of covered self-expandable metal stent (SEMSs), occurring in up to 40% of malignant colorectal obstruction management cases. Various types of covered SEMSs have been developed to reduce this risk. We aimed to compare the effectiveness and complication rates of the flare-type covered SEMS (Flare) with those of the double-layered covered SEMS (ComVi).

METHODS

We performed a prospective, randomized study in four tertiary referral centers between July 2016 and April 2018. Patients with malignant colorectal obstruction were eligible for the study. The primary outcome was migration rate as observed within the first month. Rates of technical success, clinical success, and complications within the first month were also assessed.

RESULTS

A total of 60 patients were included (mean age, 70.5 ± 12.5 years; male, 31 [51.7%]). Flare and ComVi stents were applied in 30 patients each. The Flare and ComVi groups showed comparable technical success rates (90% [27/30] vs. 96.7% [29/30], p = 0.605) and clinical success rates (85.2% [23/27] vs. 75.9% [22/29], p = 0.589). Migration occurred in three (11.1%) and four (13.8%) cases in the Flare and ComVi groups, respectively, without significant difference (p = 0.99), and the risk of other complications, including perforation and re-obstruction, did not differ between the two groups.

CONCLUSIONS

Our study indicates that both flare-shape and double-layered covered SEMSs are equally effective options for the management of malignant colorectal obstruction with low migration rates when compared with previously reported migration risk of covered SEMS.

Colonic stents for malignant bowel obstruction: current status and future prospects

Introduction: Although more than two decades are already passed from the first description of this technique, the debate remains open on the role of self-expanding metal stents (SEMS) placement in the management of malignant bowel obstruction (MBO). According to most recent data, SEMS placement is considered a safe and effective alternative treatment as a bridge to surgery(BTS). In addition, stent placement should be considered as primary option for palliative treatment of obstructing cancer.Areas covered: Current status, indication, technique, oncological outcomes, advantages, and risks of SEMS placement in MBO were reviewed.Expert commentary: The placement of colonic SEMS for palliation and for BTS in patients with MBO has been increasingly reported and it seems to have several advantages over emergency surgery. Substantial concerns of tumor seeding following SEMS placement, especially in case of perforation, have been raised in numerous studies. Actually, no significant differences are reported in oncologic long-term survival between patients undergoing stent placement as a BTS and those undergoing emergency surgery. Considering all the mentioned factors, indication for colorectal stenting should be evaluated only in highly specialized centers, in the context of multidisciplinary approach where risks and benefits of stenting are carefully weighed, especially in the BTS setting.