WallFlex colonic stent placement for management of malignant colonic obstruction: a prospective study at two centers

Short-Term Outcomes of Colorectal Stenting Using a Low Axial Force Self-Expandable Metal Stent for Malignant Colorectal Obstruction: A Japanese Multicenter Prospective Study

(1) Background: Endoscopic colorectal stenting with high technical success and safety is essential in discussing the oncological outcomes for the management of malignant colorectal obstruction. Mechanical properties of self-expandable metal stents are usually considered to affect clinical outcomes. (2) Methods: A multicenter, prospective study was conducted in Japan. A self-expandable metal stent with low axial force was inserted endoscopically. The primary endpoint was clinical success, defined as the resolution of symptoms and radiological findings within 24 h. Secondary endpoints were technical success and adverse events. Short-term outcomes of 7 days were evaluated in this study. (3) Results: Two hundred and five consecutive patients were enrolled. Three patients were excluded, and the remaining 202 patients were evaluated. The technical and clinical success rates were 97.5% and 96.0%, respectively. Major stent-related adverse events included stent migration (1.0%), insufficient stent expansion (0.5%), and stent occlusion (0.5%). No colonic perforation was observed. There were two fatal cases (1%) which were not related to stent placement. (4) Conclusions: The placement of self-expandable metal stents with low axial force is safe with no perforation and showed high technical and clinical success rates in short-term outcomes for the management of malignant colorectal obstruction.

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.

Biopsy sampling during self-expandable metallic stent placement in acute malignant colorectal obstruction: a narrative review

BACKGROUND

Histopathology is a crucial part of diagnosis and treatment guidance of colorectal cancer. In Denmark, it is not routine to biopsy during self-expandable metallic stent (SEMS) placement as a treatment option for acute colorectal obstruction of unknown etiology. This is due to lack of knowledge about the risks of hemorrhage, and thus the risk to aggravate the deteriorating overview conditions. Therefore, the aim of this study is to investigate whether there is evidence to avoid biopsy sampling during acute SEMS placement.

METHODS

The PubMed, Embase, and Cochrane Library databases were searched for relevant studies. Studies were included if they described biopsy sampling in relation to SEMS placement. Additionally, national and international guidelines were scrutinized on Google and by visiting the websites of national and international gastrointestinal societies.

RESULTS

In total, 43 studies were included in the review. Among these, one recommended biopsy during SEMS placement, three advised against biopsy, 23 just reported biopsy was performed during the procedure, and 16 reported biopsy before or after the procedure, or the timing was not specified. Among the 12 included guidelines, only two described biopsy during SEMS placement.

CONCLUSION

The literature on the subject is limited. In 24 of the 43 included studies, biopsy sampling was done during SEMS placement without reporting a decrease in the technical success rate. The included guidelines were characterized by a general lack of description of whether biopsy during SEMS placement should be performed or not. Prospective studies are needed in order to establish the real risk of hemorrhage, if any, when a biopsy is obtained.

Comparing the mechanical properties of a self-expandable metallic stent for colorectal obstruction: Proposed measurement method of axial force using a new measurement machine

OBJECTIVES

Colorectal stenting is widely performed using self-expandable metallic stents (SEMSs), but the mechanical properties have not been evaluated. Therefore, we conducted an in vitro study to evaluate the mechanical properties of colorectal SEMSs.

METHODS

Eighteen individual types and sizes of uncovered SEMSs were evaluated for their mechanical properties. Radial force was measured using a measurement machine. Axial force (AF) was measured by two methods: a conventional manual method and a new method using a measurement machine. The correlation of these two methods was evaluated. We also proposed an "AF zero border" that was defined as the angle at which the torque force disappeared.

RESULTS

Radial force versus diameter curves and AF versus angle curves were influenced by the structure and the size of each stent. There was excellent correlation of AFs measured by the new and conventional manual method (y = 21.434x, R = 0.881, P < 0.0001). Colorectal SEMSs could be categorized into five subgroups according to the mechanical properties. Most hook-wired SEMSs had the AF of zero border.

CONCLUSIONS

This is the first report to evaluate the mechanical properties of colorectal SEMSs, and these data may provide useful information for the clinical use and development of colorectal SEMS. Furthermore, the new measurement machine might standardize the measuring method of AF.

A Comparison of Open and Laparoscopic-assisted Colectomy for Obstructive Colon Cancer

BACKGROUND/AIM

We performed a retrospective multi-center cohort analysis to compare the outcomes of laparoscopic surgery vs. open surgery for obstructive colon cancer.

PATIENTS AND METHODS

A total of 455 patients with colon cancer with ileus underwent surgery at Yokohama City University Hospital and four related institutions from April 2000 to March 2016.

RESULTS

There were 414 cases in the open surgery group and 41 cases in the laparoscopic surgery group with no marked differences in the gender or age. The postoperative complication rate, according to the Clavien-Dindo classification, was lower in the laparoscopic group compared to the open surgery group. The postoperative hospital stay was 16 days in the open surgery group and 9 days in the laparoscopic surgery group (p=0.004). Among the various factors examined, the operation approach was identified as a statistically significant independent risk factor for postoperative complications (p=0.015).

CONCLUSION

Preoperative treatment for colon cancer with ileus and elective laparoscopic surgery are thought to be useful for achieving curative treatment, avoiding colostomy, and shortening the length of hospital stay.

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.

[Endoscopic treatment of benign gastrointestinal fistulas]

OBJECTIVE

To evaluate the possibility and safety of modified endoscopic stent in the treatment of benign intestinal fistulas.

MATERIAL AND METHODS

Analysis of the experience of Sklifosovsky Research Institute for Emergency Care and recent numerous foreign reports confirms that staged treatment followed by delayed radical surgery is the most perspective approach. Modified endoscopic treatment of intestinal fistulas successfully used in 10 patients is reported in the article.

RESULTS

Endoscopic stenting of various parts of gastrointestinal tract is a minimally invasive treatment of this pathology and not followed by complications and mortality. An important advantage is early closure of fistula that reduces duration of treatment and improves further social and labor rehabilitation of patients.

Endoscopic stenting in colorectal cancer

Acute malignant large bowel obstruction presents as one of the few emergencies of colorectal cancer (CRC). Management of this condition can either be by (I) upfront surgery or (II) the use of self-expanding metallic stent (SEMS) as a bridge to elective surgery. For patients with metastasis, the use of SEMS is reported to enable earlier commencement of chemotherapy. Although the use of SEMS in patients with acute malignant large bowel obstruction looks promising, it is plagued by its own set of complications and divided opinion over its long-term outcomes. Conflicting data are present, and definitive indication requires further evaluation and debate. This article will describe the typical presentation of patients with acute malignant large bowel obstruction. An introduction to the SEMS insertion procedural steps will be undertaken. Following which the article aims to review the safety profile of SEMS and the short- and long-term outcomes of SEMS in both the curative and palliative setting.

[Effectiveness of various approaches for acute malignant colonic obstruction]

AIM

To determine optimal treatment strategy for acute malignant colonic obstruction.

MATERIAL AND METHODS

349 patients with acute malignant colonic obstruction were retrospectively analyzed for the period 2005-2017. All patients were divided into two groups depending on surgical approach. Surgical group comprised 259 patients, endoscopic group - 90 patients. Both groups were comparable by gender, age, level of intestinal obstruction and duration of the disease. However, morbidity and mortality rate were significantly different.

RESULTS

In surgical group incidence of complications was 63.3%, mortality - 19.7%. In group of endoscopic stenting the same values were 8.9% and 6.7%, respectively. Significant differences of morbidity and mortality were observed between groups (p<0.05).

CONCLUSION

Endoscopic stenting should be preferred over surgery to eliminate colonic obstruction in patients with acute malignant ileus.

2017 WSES guidelines on colon and rectal cancer emergencies: obstruction and perforation

ᅟ

Obstruction and perforation due to colorectal cancer represent challenging matters in terms of diagnosis, life-saving strategies, obstruction resolution and oncologic challenge. The aims of the current paper are to update the previous WSES guidelines for the management of large bowel perforation and obstructive left colon carcinoma (OLCC) and to develop new guidelines on obstructive right colon carcinoma (ORCC).

Methods

The literature was extensively queried for focused publication until December 2017. Precise analysis and grading of the literature has been performed by a working group formed by a pool of experts: the statements and literature review were presented, discussed and voted at the Consensus Conference of the 4th Congress of the World Society of Emergency Surgery (WSES) held in Campinas in May 2017.

Results

CT scan is the best imaging technique to evaluate large bowel obstruction and perforation. For OLCC, self-expandable metallic stent (SEMS), when available, offers interesting advantages as compared to emergency surgery; however, the positioning of SEMS for surgically treatable causes carries some long-term oncologic disadvantages, which are still under analysis. In the context of emergency surgery, resection and primary anastomosis (RPA) is preferable to Hartmann’s procedure, whenever the characteristics of the patient and the surgeon are permissive. Right-sided loop colostomy is preferable in rectal cancer, when preoperative therapies are predicted.

With regards to the treatment of ORCC, right colectomy represents the procedure of choice; alternatives, such as internal bypass and loop ileostomy, are of limited value.

Clinical scenarios in the case of perforation might be dramatic, especially in case of free faecal peritonitis. The importance of an appropriate balance between life-saving surgical procedures and respect of oncologic caveats must be stressed. In selected cases, a damage control approach may be required.

Medical treatments including appropriate fluid resuscitation, early antibiotic treatment and management of co-existing medical conditions according to international guidelines must be delivered to all patients at presentation.

Conclusions

The current guidelines offer an extensive overview of available evidence and a qualitative consensus regarding management of large bowel obstruction and perforation due to colorectal cancer.

Long-term outcomes of palliative colonic stenting versus emergency surgery for acute proximal malignant colonic obstruction: a multicenter trial

Background and study aims Long-term data are limited regarding clinical outcomes of self-expanding metal stents as an alternative for surgery in the treatment of acute proximal MBO. The aim of this study was to compare the long-term outcomes of stenting to surgery for palliation in patients with incurable obstructive CRC for lesions proximal to the splenic flexure. Patients and methods Retrospective multicenter cohort study of obstructing proximal CRC patients with who underwent insertion of a SEMS (n = 69) or surgery (n = 36) from 1999 to 2014. The primary endpoint was relief of obstruction. Secondary endpoints included technical success, duration of hospital stay, early and late adverse events (AEs) and survival. Results Technical success was achieved in 62/69 (89.8 %) patients in the SEMS group and in 36 /36 (100 %) patients who underwent surgery (P = 0.09). In the SEMS group, 10 patients underwent stenting as a bridge to surgery and 59 underwent stent placement for palliation. Clinical relief was achieved in 78 % of patients with stenting and in 100 % of patients who underwent surgery (P < 0.001). Patients with SEMS had significantly less acute AEs compared to the surgery group (7.2 % vs. 30.5 %, P = 0.003). Hospital mortality for the SEMS group was 0 % compared to 5.6 % in the surgery group (P = 0.11). Patients in the SEMS group had a significantly shorter median hospital stay (4 days) as compared to the surgery group (8 days) (P < 0.01). Maintenance of decompression without the recurrence of bowel obstruction until death or last follow-up was lower in the SEMS group (73.9 %) than the surgery group (97.3 %; P = 0.003). SEMS placement was associated with higher long-term complication rates compared to surgery (21 % and 11 % P = 0.27). Late SEMS AEs included occlusion (10 %), migration (5 %), and colonic ulcer (6 %). At 120 weeks, survival in the SEMS group was 5.6 % vs. 0 % in the surgery group (P = 0.8). Conclusions Technical and clinical success associated with proximal colonic obstruction are higher with surgery when compared to SEMS, but surgery is associated with longer hospital stays and more early AEs. SEMS should be considered the initial mode of therapy in patients with acute proximal MBO and surgery should be reserved for SEMS failure, as surgery involves a high morbidity and mortality.

Safety and efficacy of palliative systemic chemotherapy combined with colorectal self-expandable metallic stents in advanced colorectal cancer: A multicenter study

PURPOSE

Self-expandable metallic stent (SEMS) placement is an accepted palliative therapy for management of acute malignant bowel obstruction in advanced colorectal cancer. Nevertheless, data are lacking on the effects of systemic chemotherapy combined with colorectal SEMS. The aim of this study was to investigate the safety and efficacy of palliative chemotherapy for advanced colorectal cancer combined with colorectal SEMS placement.

PATIENTS AND METHODS

This multicentre retrospective study included all consecutive advanced colorectal cancer patients who received first-line palliative chemotherapy combined with endoscopic stenting for colorectal cancer with obstruction. We analyzed the number of cycles and the type of combination used. The primary endpoint was overall survival. Secondary endpoints included progression-free survival, response rate, grade 3-4 toxicity and the outcomes of SEMS for malignant colorectal obstruction.

RESULTS

A total of 38 patients were included. Among them, 25 patients received oxaliplatin and 5-fluorouracil combination chemotherapy. Objective response and stabilization occurred in 38 and 24% of patients, respectively. The median overall survival and progression-free survival from the start of chemotherapy were 18 and 5months, respectively. The objective response rate and overall disease control rate were 38 and 62%, respectively. Toxicity was generally acceptable. Major complications related to stenting included perforation (8%), stent migration (5%), and reobstruction secondary to tumor ingrowths (13%).

CONCLUSIONS

Chemotherapy combined with colonic stenting as a first-line treatment seems to be a valid option in advanced colorectal cancer patients with malignant colorectal obstruction.

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.

Role of self-expanding metal stents in patients with malignant colorectal obstruction: A systematic review and meta-analysis

AIM: To assess the safety and efficacy of self-expandable metal stents (SEMSs) for malignant colorectal obstruction.

METHODS: Data regarding technical success, clinical success, and procedure related complications were collected from included studies. DerSimonian-Laird random effects model was used to generate the overall outcome. Thirty international studies with a total of 2058 patients with malignant colorectal obstruction were included.

RESULTS: The technical and clinical success rates for SEMS placement were 94% (95%CI: 92-96) and 91% (95%CI: 88-93), respectively. Overall complication rate for SEMS was 23% (95%CI: 18-29). Stent migration 8% (95%CI: 6-10) and stent obstruction 8% (95%CI: 6-11) were the most common complications, followed by perforation 5% (95%CI: 4%-7%). Surgical or endoscopic re-interventions were needed in 14% (95%CI: 10-18) of patients. Endoscopic repeat stent placement was required in 8% (95%CI: 6-10), while surgical intervention was needed in 6% (95%CI: 4-8).

CONCLUSION: SEMS are effective when used as palliation or bridge to surgery for malignant colorectal obstruction with high technical and clinical success. About 14% of patients require repeat endoscopic or surgical intervention for stent failure or to manage stent related complications.

A Japanese prospective multicenter study of self-expandable metal stent placement for malignant colorectal obstruction: short-term safety and efficacy within 7 days of stent procedure in 513 cases

BACKGROUND

Endoscopic self-expandable metal stent placement has been used as an alternative to surgery for malignant colorectal obstruction; however, factors affecting its clinical outcome are unclear.

OBJECTIVE

To clarify the short-term safety and efficacy of endoscopic self-expandable metal stent placement for malignant colorectal obstruction and to identify factors associated with its clinical and technical failure.

DESIGN

Prospective clinical cohort study.

SETTING

Fourteen academic centers and 32 community hospitals.

PATIENTS

A total of 513 consecutive patients with malignant colorectal obstruction.

INTERVENTION

Endoscopic self-expandable metal stent placement, sharing of stent placement methods among participating facilities.

MAIN OUTCOME MEASUREMENTS

The primary endpoint was clinical success, defined as symptom and radiological finding resolution within 24 hours. Secondary endpoints were technical success and adverse events. The follow-up period was 7 days.

RESULTS

The clinical and technical success rates were 95.5% and 97.9%, respectively. Major adverse events included perforation (2.1%), stent migration (1.0%), and stent occlusion (0.8%). The main causes of perforation were the procedure itself (0.8%) and comorbidities (obstructive colitis and impending perforation) not apparent before stent placement (0.6%). Extrinsic tumor origin was independently associated with the clinical failure after stent placement (odds ratio 4.23; 95% confidence interval, 1.21-14.79; P = .02). Stricture marking trended toward a negative association with technical failure (P = .09).

LIMITATIONS

Noncomparative study.

CONCLUSION

Strict inclusion criteria and stricture marking may improve the technical and clinical success of stent placement.

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.

Efficacy and complications in the use of self-expanding colonic stents: an analysis of 15 years' experience

OBJECTIVE

To analyze the efficacy and safety of the procedure for placing self-expanding stents in the colon. To evaluate the factors associated with complications. To analyze the dose of radiation delivered in the procedure.

MATERIAL AND METHODS

This was a retrospective descriptive study of 478 procedures done at a single center to place self-expanding metallic stents in the colon. A total of 423 nitinol stents and 79 stainless steel stents were placed. We included all colonic obstructions, of which 446 had malignant causes and 8 had benign causes. We excluded patients with intestinal perforation, severe colonic bleeding, short life expectancy, or lesions located less than 5 cm from the anus. We collected the dosimetric data and analyzed the technical success, clinical success, and complications during follow-up.

RESULTS

The procedure was a technical success in 92.26% of cases (n=441) and a clinical success in 78.45% (n=375); complications occurred during follow-up in 18.5% of cases. Complications occurred more frequently with the stainless steel stents than with the nitinol stents (OR: 3.2; 95% CI: 1.8-5.7). The mean value of the dose area product was 35 Gy*cm(2). When instead of being done by the interventional radiologist working together with an endoscopist the procedure was done exclusively by the interventional radiologist, the time under fluoroscopy (p=0.001), dose area product (p=0.029), and kinetic energy released per unit mass (p=0.001) were greater.

CONCLUSION

The procedure for placing self-expanding colonic stents is efficacious and safe with an acceptable rate of complications. The doses of radiation delivered were low, and the radiation doses and time under fluoroscopy were lower when the procedure was done together with an endoscopist.

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.

Influence of K-ras status and anti-tumour treatments on complications due to colorectal self-expandable metallic stents: a retrospective multicentre study

BACKGROUND

This study aimed to explore the relationship between K-ras status, anti-tumour treatments, and the complications of colorectal self-expandable metallic stenting in colorectal cancer.

METHODS

This is a retrospective, multicentre study of 91 patients with obstructive advanced colorectal cancer palliated with enteral stents between 2007 and 2011.

RESULTS

K-ras wild-type tumours were diagnosed in 44 patients (48.4%); 82 (90.1%) received chemotherapy and 45 (49.4%) had additional biological therapy (34 bevacizumab, 11 cetuximab). Twenty-one (23.1%) experienced stent-related complications: 11 (52.4%) occurred in the K-ras mutant group (P=0.9). K-ras wild-type patients were not less likely to develop adverse events than K-ras mutant patients (OR, 0.99; 95% CI: 0.4-2.7). Overall mean time to complication was 167.6 days (range 4-720 days), with no difference between the two groups (141 vs. 197 days; P=0.5). Chemotherapy did not influence the risk of complications (OR, 0.56; 95% CI: 0.14-2.9), and there was no evidence that patients treated with chemotherapy and cetuximab were more likely to experience stent-related complications than patients treated with chemotherapy alone, or untreated (OR, 1.2; 95% CI: 0.2-5.9). Although perforation rates were higher with bevacizumab-based treatment (11.8% vs. 7%), this result was not statistically significant (P=0.69).

CONCLUSIONS

K-ras mutation status, chemotherapy, and biological treatments should not influence colorectal stent-related complication rates.

Self-expandable metal stents for malignant colonic obstruction: data from a retrospective regional SIED-AIGO study

BACKGROUND

Self-expandable metal stents are a non-surgical option for the treatment of symptomatic malignant colorectal obstruction as palliative treatment or as a bridge to surgery.

AIMS

To report data from a regional study on self-expandable metal stent (SEMS) placement for malignant colorectal obstruction.

METHODS

Two hundred and four patients (male 54.9%, mean age of 69.5 ± 14.2) were retrospectively evaluated and data on technical and clinical success, and complications, were analyzed.

RESULTS

Technical and clinical success rates were 99% and 94.6% respectively, with 36.7% treated on an emergency basis and 63.3% electively. Palliative treatment was administered to 70.1%, and as a bridge to surgery for 29.9%. Complications were 17 neoplastic ingrowths, 10 stent migrations, and 4 perforations. Palliative treatment was associated with a higher risk of stent ingrowth (p=0.003), and chemotherapy with a lower risk of stent ingrowth (p=0.009).

CONCLUSION

This regional study, although it has certain limitations, confirms the positive role of self-expandable metal stents in the treatment of symptomatic malignant colorectal obstruction, and that chemotherapy decreases the risk of ingrowth.

Status and literature review of self-expandable metallic stents for malignant colorectal obstruction

Use of colorectal stents has increased dramatically over the last decades. Colorectal stents offer an alternative way to relieve fatal intestinal obstruction and can take place of emergency surgery, which associated with significant morbidity and mortality and a high incidence of stoma creation, to elective resection. Although there remain a few concerns regarding the use of stents as a bridge to surgical resection, use of self-expandable metallic stents for palliation in patients with unresectable disease has come to be generally accepted. Advantages of colorectal stents include acute restoration of luminal patency and allowance of time for proper staging and surgical optimization, and the well-known disadvantages are procedure-related complications including perforation, migration, and stent failure. General indications, procedures, and clinical outcomes as well as recent evidences regarding the use of colorectal stents will be discussed in this review.

Mmp-9 expression after metallic stent placement in patients with colorectal cancer: association with in-stent restenosis

PURPOSE

To verify the expression of matrix metalloproteinase (MMP)-9 in stent-induced hyperplastic tissue from patients with colorectal cancer who received colorectal stents as a bridge to surgery.

MATERIALS AND METHODS

This prospective study was institutional review board-approved, and informed consent was obtained from all patients. Eleven patients (nine men, two women; mean age, 67 years; age range, 53-82 years) with malignant colorectal obstructions who received a colorectal stent between May and December 2010 were included. Tissue specimens were analyzed for MMP-9 and MMP-2 expression. After resection, the tissue was segmented into three parts: tumor tissue, stent-induced tissue hyperplasia, and normal colon tissue. MMP-9 and MMP-2 expression were determined by using zymography, Western blot analysis, and real-time reverse-transcription (qRT) polymerase chain reaction (PCR). Significance of differences between groups was evaluated with Friedman analysis of variance test. Signed-rank test was used to determine differences between malignant tumor tissue and stent-induced hyperplastic tissue groups.

RESULTS

Stent placement was technically successful in all 11 patients. Stent-induced hyperplastic tissues were found in all patients. Zymography (P = .003) and Western blot analysis (P = .008) showed that expression of MMP-9 was higher in malignant tumor tissue and stent-induced hyperplastic tissue groups compared with normal colorectal tissue group, demonstrating significant differences between groups but no significant differences between malignant tumor and stent-induced hyperplastic tissues. As for results of qRT PCR analysis, the stent-induced hyperplastic tissue group showed increases in messenger RNA expression level of MMP-9 compared with the malignant tumor tissue group (50.42-fold ± 66.30 higher).

CONCLUSION

High expression of MMP-9 is closely associated with stent-induced colorectal tissue hyperplasia in patients with colorectal cancer.

The new nitinol conformable self-expandable metal stents for malignant colonic obstruction: a pilot experience as bridge to surgery treatment

Introduction. Self-expandable metal stents (SEMS) are a nonsurgical option for treatment of malignant colorectal obstruction also as a bridge to surgery approach. The new nitinol conformable stent has improved clinical outcomes in these kinds of patients. We report a pilot experience with nitinol conformable SEMS placement as bridge to surgery treatment in patients with colorectal obstruction. Materials and Methods. Between April and August 2012, we collected data on colonic nitinol conformable SEMS placement in a cohort of consecutive symptomatic patients, with malignant colorectal obstruction, who were treated as a bridge to surgery. Technical success, clinical success, and adverse events were recorded. Results. Ten patients (7 male (70%)), with a mean age of 69.2 ± 10.1, were evaluated. The mean length of the stenosis was 3.6 ± 0.6 cm. Five patients (50%) were treated on an emergency basis. The median time from stent placement to surgery was 16 days (interquartile range 7–21). Technical and clinical success was achieved in all patients with a significant early improvement of symptoms. No adverse events due to the SEMS placement were observed. Conclusion. This pilot study confirmed the important role of nitinol conformable SEMS as a bridge to surgery option in the treatment of symptomatic malignant colorectal obstruction.

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.

Colonic stenting: a practical update

Colonic stenting is part of the UK service provision guidelines for colorectal cancer. However, there are issues about availability and expertise within the UK, and controversies remain regarding various clinical and technical aspects of the technique. Based on the current evidence, this article will provide a practical update on the indications, the clinical and technical considerations and the remaining unanswered questions regarding colonic stenting.

Meta-analysis of randomized trials comparing endoscopic stenting and surgical decompression for colorectal cancer obstruction

PURPOSE

Surgical decompression is the traditional treatment for acute colorectal cancer obstruction. In recent years, colorectal stenting has been used to relieve the obstruction. This study used meta-analytic techniques to compare colonic stenting versus surgical decompression for colorectal cancer obstruction.

METHODS

A comprehensive search of several databases was conducted. The search identified 321 potential abstracts and titles of which eight randomized trials involving 353 patients were retrieved in full text. A meta-analysis of the studies included was carried out to identify the differences in outcomes between the two procedures.

RESULTS

The pooled analysis showed no significant differences for mortality (odds ratio (OR) 0.91) and morbidity (OR 2.05) rates between the two strategies while the permanent stoma creation rate was significantly higher in the surgical group as compared to the stent group (OR 3.12). By comparing surgery and colonic stenting in studies which analyzed the use of stenting as a "bridge to surgery," the pooled analysis showed that primary anastomosis was more frequent in the stent group as compared to the surgical group (OR 0.42), and the stoma creation was more frequent in the surgical group as compared to the stent group (OR 2.36).

CONCLUSION

Our study suggested that, in patients with acute colorectal cancer obstruction, stent placement improved several outcomes, such as primary anastomosis, stoma formation, and permanent stoma, while it failed to show an improvement in mortality and morbidity risk.

Feasibility of a new self-expandable metallic stent for patients with malignant colorectal obstruction

AIM

Stent migration due to peristalsis of the colon is one of the unresolved complications of colonic self-expandable metallic stent (SEMS) placement. Axial force (AF), a recovery force of the stent to a straight position after bending, has been considered a factor influencing the conformability of the digestive tract. An uncovered SEMS (Niti-S Enteral Colonic Uncovered Stent, D-type; Taewoong, Inc., Gimpo, South Korea) with improved conformability is considered to decrease migration.

METHODS

Thirty three consecutive patients with symptomatic colorectal obstruction between March 2006 and December 2011 underwent endoscopic stent placement for palliation to estimate the efficacy and safety of Niti-S stents prospectively in four tertiary referral centers.

RESULTS

Technical and clinical success rates were 100% and 97%, respectively. Seventeen patients had the following complications: ingrowth (n = 6), overgrowth (n = 1), collapse of the SEMS (n = 1), stool impaction (n = 2), migration (n = 1), bleeding (n = 3), and tenesmus (n = 3). The patient with migration had no recurrent symptoms until death. Of these 17 patients, 10 required re-interventions. Seven patients underwent an additional SEMS implantation. One patient underwent surgery for stoma creation. Two patients had stool impaction, and they underwent endoscopic cleaning. The median duration of patency was 347.0 ± 65.5 days. The mean survival time after stent insertion was 240.1 ± 39.9 days.

CONCLUSION

The new SEMS effectively relieves malignant colorectal obstruction. Good conformability, according to the very low AF, may contribute to the low incidence of migration.

A temporary self-expanding metallic stent for malignant colorectal obstruction

AIM: To investigate the clinical safety and efficacy of a temporary self-expanding metallic stent (SEMS) for malignant colorectal obstruction.

METHODS: From September 2007 to June 2012, 33 patients with malignant colorectal obstruction were treated with a temporary SEMS. The stent had a tubular configuration with a retrieval lasso attached inside the proximal end of the stent to facilitate its removal. The SEMS was removed one week after placement. Clinical examination, abdominal X-ray and a contrast study were prospectively performed and both initial and follow-up data before and at 1 d, 1 wk, and 1 mo, 3 mo, 6 mo and 12 mo after stent placement were obtained. Data collected on the technical and clinical success of the procedures, complications, need for reinsertion and survival were analyzed.

RESULTS: Stent placement and removal were technically successful in all patients with no procedure-related complications. Post-procedural complications included stent migration (n = 2) and anal pain (n = 2). Clinical success was achieved in 31 (93.9%) of 33 patients with resolution of bowel obstruction within 3 d of stent removal. Eleven of the 33 patients died 73.81 ± 23.66 d (range 42-121 d) after removal of the stent without colonic re-obstruction. Clinical success was achieved in another 8 patients without symptoms of obstruction during the follow-up period. Reinsertion of the stent was performed in the remaining 12 patients with re-obstruction after 84.33 ± 51.80 d of follow-up. The mean and median periods of relief of obstructive symptoms were 97.25 ± 9.56 d and 105 ± 17.43 d, respectively, using Kaplan-Meier analysis.

CONCLUSION: Temporary SEMS is a safe and effective approach in patients with malignant colorectal obstruction due to low complication rates and good medium-term outcomes.

Favorable long-term clinical outcome of uncovered D-weave stent placement as definitive palliative treatment for malignant colorectal obstruction

BACKGROUND

Most self-expandable metallic stents for colorectal placement are uncovered because of the high migration rate of covered stents. However, the optimal stent design for colorectal use remains unclear.

OBJECTIVE

The purpose of this study was to evaluate the efficacy and safety of a double-wire woven uncovered stent for definitive palliative treatment of malignant colorectal obstruction.

DESIGN

This study was a prospective, single-arm, observational clinical study of patients enrolled between December 2005 and September 2010.

SETTINGS

This study was conducted at a referral hospital in Japan.

PATIENTS

Twenty-four consecutive patients with malignant colorectal obstruction were included in the study.

INTERVENTIONS

A double-wire woven uncovered stent was placed by use of a standard through-the-scope endoscopic placement technique.

MAIN OUTCOME MEASURES

Technical, initial clinical, and long-term clinical success were measured. Long-term clinical success was defined as sustained relief of obstructive symptoms without reintervention until the patient's death.

RESULTS

The Karnofsky performance status score before stent placement was 60 (median, interquartile range, 42.5-67.5). Twenty of 24 patients had primary colorectal cancer, and 4 had extracolorectal malignancies. The site of obstruction was the ascending colon in 10 patients, descending colon in 4 patients, sigmoid colon in 7 patients, and rectum in 3 patients. Technical, initial, and long-term clinical success rates were 100%, 100%, and 83%. Median stent patency time was 149 days (interquartile range, 45-198 days). Median survival time after stent placement was 155 days (interquartile range, 68-231 days). Four patients (17%) had negative outcomes including stent occlusion by tumor ingrowth (8%) and stent migration (8%). The highest Karnofsky performance status score after stent placement was 70 (median; interquartile range, 50-70). The Karnofsky performance status score improved after stent placement (p = 0.002).

LIMITATIONS

This study was limited because it was a single-arm, single-center study, and it had a small sample size.

CONCLUSIONS

Endoscopic placement of double-wire woven uncovered stents is effective and safe as definitive palliative treatment for patients with malignant colorectal obstruction.

Colorectal Stents Orient Specimens and Induce Artifacts That Mimic Crohn Disease

Colorectal malignancies may be stented to alleviate obstruction. The stent is a polarized and braided network of metallic wires. Pathology associated with colorectal stents is yet to be described. The authors reviewed 7 cases involving stented colorectal segments from patients lacking clinical suspicion of Crohn disease. In 4 cases, orientation of the specimens and stents matched the corresponding anatomic landmarks. In 3 cases, the specimens lacked helpful anatomic landmarks, and orientation was possible only after correlating with the intrinsic polarity of the stents. Stented areas showed artifacts resembling Crohn disease, including rounded cobblestones, pseudopolyps, and simple fissures, as well as unique artifacts including rhomboid cobblestones, complex fissures, oblique fissures with remarkably straight edges, and conical fragments of tissue that appeared to float. Crohn disease was misdiagnosed in 1 case in which the stent was removed intraoperatively and was never received. Colorectal stents help orient ambiguous specimens and induce patterned injury that can be confused with Crohn disease.

Duodenal and colonic stent placement with 0.025″ and 0.035″ guidewires is equally safe and effective

BACKGROUND

The overwhelming majority of reported duodenal and colonic SEMS placements in the literature have used the 0.035″ guidewire almost to the exclusion of guidewires of other diameters.

AIMS

The purpose of this study was to compare technical and clinical outcomes in patients undergoing duodenal or colonic SEMS placement with 0.025″ or 0.035″ guidewires.

METHODS

This was a retrospective study to compare technical and clinical outcomes and complications of patients receiving duodenal or colonic SEMS placement with a 0.035″ guidewire to those undergoing placement with a 0.025″ guidewire.

RESULTS

A total of 34 duodenal and 30 colonic stent placement procedures were performed in 59 patients. Technical success was achieved in all duodenal stent placement procedures. The difference in mean GOOSS score increase after stent placement was not statistically significant between the 0.035″ and 0.025″ guidewire groups (P = 0.49). Complications were not statistically significantly different between the two groups undergoing gastroduodenal stenting. Technical and clinical success was achieved in all colonic stent placement procedures. There were no statistically significant differences in complication rates between the two groups undergoing colonic stenting. Procedure times were not significantly different using either wire type.

CONCLUSIONS

Our study shows that both 0.035″ and 0.025″ guidewires were equally effective with regards to technical success, clinical success, and with regards to the development of complications.

Dual-design expandable colorectal stent for a malignant colorectal obstruction: preliminary prospective study using new 20-mm diameter stents

Objective

To evaluate the safety and effectiveness of a 20-mm diameter dual-design expandable colorectal stent for malignant colorectal obstruction.

Materials and Methods

The study series included 34 patients with malignant colorectal obstruction who underwent implantation of a 20-mm dual-design expandable colorectal stent in our department between March 2009 and June 2010. The 20-mm dual-design expandable colorectal stent was placed by using a 3.8-mm delivery system that had 28-mm diameter proximal and distal ends. Among the 34 patients, stent placement for palliation was performed in 20 patients, while stent placement for bridge to surgery was performed in 14 patients.

Results

A 97% (33 of 34) success rate was achieved for the stent placement. The perforation rate in the bridge to surgery group was 7% (1 of 14), compared to 0% (0 of 19) in palliative group. Migration occurred in one of 33 patients (3%) at 30 days after stent placement.

Conclusion

The placement of a 20-mm diameter dual-design stent appears to be clinically safe and effective for the management of colorectal obstruction, with low perforation and migration rates.

Colonic stenting as a bridge to surgery in malignant large-bowel obstruction: a report from two large multinational registries

OBJECTIVES

To date, this is the largest prospective series in patients with malignant colorectal obstruction to evaluate the effectiveness and safety of colonic self-expanding metal stents (SEMSs) as an alternative to emergency surgery. SEMSs allow restoration of bowel transit and careful tumor staging in preparation for elective surgery, hence avoiding the high morbidity and mortality associated with emergency surgery and stoma creation.

METHODS

This report is on the SEMS bridge-to-surgery subset enrolled in two multicenter international registries. Patients were treated per standard of practice, with documentation of clinical and procedural success, safety, and surgical outcomes.

RESULTS

A total of 182 patients were enrolled with obstructive tumor in the left colon (85%), rectum (11%), or splenic flexure (4%). Of these patients, 86% had localized colorectal cancer without metastasis. Procedural success was 98% (177/181). Clinical success was 94% (141/150). Elective surgery was performed in 150 patients (9 stomas) and emergency surgery in 7 patients for treatment of a complication (3 stomas). The overall complication rate was 7.8% (13/167), including perforation in 3% (5/167), stent migration in 1.2% (2/167), bleeding in 0.6% (1/167), persistent colonic obstruction in 1.8% (3/167), and stent occlusion due to fecal impaction in 1.2% (2/167). One patient died from complications related to surgical management of a perforation.

CONCLUSIONS

SEMSs provide an effective bridge to surgery treatment with an acceptable complication rate in patients with acute malignant colonic obstruction, restoring luminal patency and allowing elective surgery with primary anastomosis in most patients.

Self-expandable metal stents for relieving malignant colorectal obstruction: short-term safety and efficacy within 30 days of stent procedure in 447 patients

BACKGROUND

The self-expandable metal stent (SEMS) can alleviate malignant colonic obstruction and avoid emergency decompressive surgery.

OBJECTIVE

To document performance, safety, and effectiveness of colorectal stents used per local standards of practice in patients with malignant large-bowel obstruction to avoid palliative stoma surgery in incurable patients (PAL) and facilitate bowel decompression as a bridge to surgery for curable patients (BTS).

DESIGN

Prospective clinical cohort study.

SETTING

Two global registries with 39 academic and community centers.

PATIENTS

This study involved 447 patients with malignant colonic obstruction who received stents (255 PAL, 182 BTS, 10 no indication specified).

INTERVENTION

Colorectal through-the-scope SEMS placement.

MAIN OUTCOME MEASUREMENTS

The primary endpoint was clinical success at 30 days, defined as the patient's ability to maintain bowel function without adverse events related to the procedure or stent. Secondary endpoints were procedural success, defined as successful stent placement in the correct position, symptoms of persistent or recurrent colonic obstruction, and complications.

RESULTS

The procedural success rate was 94.8% (439/463), and the clinical success rates were 90.5% (313/346) as assessed on a per protocol basis and 71.6% (313/437) as assessed on an intent-to-treat basis. Complications included 15 (3.9%) perforations, 3 resulting in death, 7 (1.8%) migrations, 7 (1.8%) cases of pain, and 2 (0.5%) cases of bleeding.

LIMITATIONS

No control group. No primary endpoint analysis data for 25% of patients.

CONCLUSION

This largest multicenter, prospective study of colonic SEMS placement demonstrates that colonic SEMSs are safe and highly effective for the short-term treatment of malignant colorectal obstruction, allowing most curable patients to have 1-step resection without stoma and providing most incurable patients minimally invasive palliation instead of surgery. The risk of complications, including perforation, was low.

Clinical outcomes and risk factors for technical and clinical failures of self-expandable metal stent insertion for malignant colorectal obstruction

BACKGROUND

Although self-expandable metal stent (SEMS) insertion is widely used for relief of malignant colorectal obstructions, the immediate technical and clinical failure rates of SEMSs and the associated risk factors remain largely unknown.

OBJECTIVE

To identify rates and factors predictive of technical and clinical failure of SEMSs when their use is attempted for the decompression of malignant colorectal obstruction.

DESIGN

Retrospective chart review.

SETTING

A tertiary-care academic medical center in South Korea.

PATIENTS

This study involved a total of 412 patients with malignant colorectal obstruction in whom SEMS insertion was attempted.

INTERVENTION

Placement of colonic SEMSs.

MAIN OUTCOME MEASUREMENTS

Technical success and immediate and long-term clinical success rates.

RESULTS

Technical and clinical failures were found in 36 of 276 patients (13.0%) and 39 of 240 patients (16.3%) in the palliative group, respectively, and in 3 of 136 patients (2.2%) and 7 of 133 patients (5.3%) in the preoperative group, respectively. Factors associated with technical failure were extracolonic origin of tumor, the presence of carcinomatosis, and a proximal obstruction site. Factors associated with long-term clinical failure in the palliative group were combined dilation procedure, no additional chemotherapy, and extracolonic origin of the tumor. In the preoperative group, only older patients had both higher technical failure and clinical failure rates.

LIMITATIONS

This was a single-institution, retrospective analysis.

CONCLUSION

Although colorectal SEMS placement is generally safe and effective, it is associated with clinically important technical and clinical failure rates. The identification of risk factors for the failure of colorectal SEMSs found in this study might help physicians decide between surgical decompression and endoscopic stenting in patients with malignant colorectal obstruction.

Enteral stents

The American Society for Gastrointestinal Endoscopy (ASGE) Technology Committee provides reviews of existing, new, or emerging endoscopic technologies that have an impact on the practice of GI endoscopy. Evidence-based methodology is used, with a MEDLINE literature search to identify pertinent clinical studies on the topic and a MAUDE (U.S. Food and Drug Administration Center for Devices and Radiological Health) database search to identify the reported complications of a given technology. Both are supplemented by accessing the "related articles" feature of PubMed and by scrutinizing pertinent references cited by the identified studies. Controlled clinical trials are emphasized, but in many cases, data from randomized, controlled trials are lacking. In such cases, large case series, preliminary clinical studies, and expert opinions are used. Technical data are gathered from traditional and Web-based publications, proprietary publications, and informal communications with pertinent vendors. Technology Status Evaluation Reports are drafted by 1 or 2 members of the ASGE Technology Committee, reviewed and edited by the committee as a whole, and approved by the Governing Board of the ASGE. When financial guidance is indicated, the most recent coding data and list prices at the time of publication are provided. For this review, the MEDLINE database was searched through August 2010 for articles related to enteral, esophageal, duodenal, and colonic stents. Technology Status Evaluation Reports are scientific reviews provided solely for educational and informational purposes. Technology Status Evaluation Reports are not rules and should not be construed as establishing a legal standard of care or as encouraging, advocating, requiring, or discouraging any particular treatment or payment for such treatment.

Outcomes of secondary stent-in-stent self-expandable metal stent insertion for malignant colorectal obstruction

BACKGROUND

Although self-expandable metal stents (SEMSs) are widely used for the treatment of malignant colorectal obstruction, they often become occluded by tumor ingrowth.

OBJECTIVES

To determine the therapeutic effectiveness of secondary stent-in-stent SEMS insertion for the management of occluded SEMS in patients with malignant colorectal obstruction and to identify predictive factors associated with clinical outcomes in terms of immediate clinical success, stent patency, and complications.

DESIGN

Retrospective case series.

SETTING

A tertiary-care academic medical center in South Korea.

PATIENTS

Between November 2005 and July 2010, among a total of 309 patients who underwent SEMS insertion for unresectable malignant colorectal obstruction at Severance Hospital, 87 underwent secondary SEMS insertion. Of these, 36 patients underwent secondary SEMS placement as stent-in-stent.

INTERVENTIONS

Placement of secondary colorectal stent-in-stent SEMSs.

MAIN OUTCOME MEASUREMENTS

Immediate and long-term clinical success and complications.

RESULTS

Immediate clinical success was achieved in 27 of 36 patients (75%), and the median duration of stent patency was 170 days. Factors associated with immediate clinical success included a long duration between the previous stent and stent-in-stent insertion. Moreover, the absence of carcinomatosis was associated with long-term clinical success.

LIMITATIONS

This was a retrospective, nonrandomized, single-center study.

CONCLUSIONS

Secondary stent-in-stent SEMS placement led to good outcomes in patients with malignant colorectal obstruction, despite a slightly lower success rate compared with primary SEMS placement. Patency duration of the primary SEMS and carcinomatosis were important factors predictive of immediate and long-term clinical success of stent-in-stent insertion, respectively.

Expandable metal stents for malignant colorectal strictures

The surgical management of malignant colorectal obstruction is still controversial and has higher associated mortality and complication rates compared with elective surgery. Placement of self-expanding metallic stents (SEMS) has been proposed as an alternative therapeutic approach for colonic decompression of patients with acute malignant obstruction. SEMS placement may be used both as a bridge to surgery in patients who are good candidates for curative resection and for palliation of those patients presenting with advanced stage disease or with severe comorbid medical illnesses.

Through-the-scope large diameter self-expanding metal stent placement as a safe and effective technique for palliation of malignant colorectal obstruction: a single center experience with a long-term follow-up

OBJECTIVE

The aim of this study was to evaluate the outcomes of through-the-scope (TTS) large diameter self-expanding metal stent (SEMS) placement for palliation of malignant colorectal obstruction.

MATERIAL AND METHODS

Between January 2005 and December 2009, all patients who underwent endoscopic SEMS placement for palliation of malignant colorectal obstruction were prospectively enrolled.

RESULTS

Thirty-nine patients (17M and 22F; mean age 75.9 ± 10.6 years, range 50-91) were enrolled. The most frequent location was the sigmoid colon (13 cases). The causes of obstruction were colorectal malignancy in 32 patients and extracolonic malignancy in 7. Technical success was achieved in 36/39 patients (92.3%) and clinical success in 35/39 patients (89.7%). Technical failure was related to female sex (p = 0.04) and the extracolonic etiology of the stricture (p < 0.001). There were three early complications: two procedure-related perforations successfully managed conservatively and one hemorrhage treated with APC. Early complications were related to the location of strictures at the recto-sigmoid junction (p < 0.001). Late complications occurred in 10 patients: 8 of these patients experienced occlusive symptoms (attributable to tumor ingrowth in 5 cases and stool impaction in 3 cases); the remaining 2 were one case of tumor ingrowth with sub-occlusive symptoms and hemorrhage, and one case of distal migration. There was no procedure-related mortality and all complications were managed without surgical intervention. SEMS patency duration was 236 ± 128 days (range 31-497) and mean survival of the patients was 259 ± 121 days (range, 32-511).

CONCLUSIONS

In our experience, TTS large-diameter SEMS placement is a safe and effective treatment for palliation of malignant colorectal obstruction.

Severity of initial stent angulation predicts reintervention after successful palliative enteral stenting for malignant luminal obstruction

BACKGROUND AND AIM

Recurrent stent obstruction necessitating reintervention is problematic and incompletely understood. The aim of the present study was to identify factor(s) predisposing to reintervention.

METHODS

Retrospective review of patients (n = 117) referred to a single major endoscopic referral centre for palliative enteral stenting from 1999 to 2006. Twelve were excluded due to inadequate follow-up data (n = 7) or initial radiographic documentation (n = 5). A total of 105 patients (gastroduodenal n = 57, colonic n = 48) were therefore analyzed. The primary outcome of interest was recurrent obstruction necessitating reintervention. Kaplan-Meier analysis of potential factors predisposing to reintervention, including stent angulation (mild [<15°], moderate [15°-90°], severe [>90°]) was completed for 98 patients (technically successful enteral stenting).

RESULTS

Technical and clinical success were achieved in 98 of 105 (93.3%) and 92 of 98 (93.9%) cases, respectively. Post-stenting median survival was 97.5 days (range 3-1054). Eighteen patients (18.4%) required reintervention for stent obstruction at a median time to reintervention of 85 days (range 7-481). Increased stent angulation (severe vs mild hazard ratio 6.73 (95% confidence interval 1.59-27.59), P = 0.009) was the only statistically significant factor in multivariate analysis predicting reintervention.

CONCLUSIONS

Despite its limitation as a retrospective review, this study found that reintervention for stent obstruction is necessary in almost one in five cases, and increasing severity of stent angulation is the most important risk factor.

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

INTRODUCTION

Stent insertion plays an important part in the management of acute colonic obstruction. There are limited data on factors influencing short- and long-term success.

AIMS AND METHODS

We investigated indications, technical and clinical success rates, complication rates and the factors influencing them. Patients were identified from our prospective colonic stent database (2000-2008).

RESULTS

One hundred and four stents were attempted in 96 patients (technical success rate, 83.3%). Clinical short-term success was observed in 74 (77.1%) patients. Follow-up data available for 57 patients showed clinical long-term success in 77% (44/57). Multiple logistic regression analysis showed a significant decline in technical success over the study period (p = 0.041). Patients with colonic malignancy had significantly higher long-term success rates (81%), compared to those with extra-colonic malignancies (43%) (p = 0.049). Length of stent and site of obstruction were not significant factors. Early complications occurred in 10%, and late complications, in 26.3% of cases.

CONCLUSION

Colonic stent insertion provides symptom relief in over 70% when used as a long-term solution. Complication rates are high, and a significant minority of patients requires re-intervention. Obstruction caused by extra-colonic malignancy is far less likely to be permanently palliated by a stent, in comparison to colonic malignancy.