Colonic stenting: technique, technology, and outcomes for malignant and benign disease

Endometriosis as an Uncommon Cause of Intestinal Obstruction-A Comprehensive Literature Review

The prevalence of intestinal endometriosis has been estimated to be between 3% and 37% of all endometriosis cases. Cases of intestinal occlusion due to endometriosis foci on the small bowel and on the large bowel are even rarer, with a reported prevalence of 0.1-0.7%. The aim of this literature review was to summarize the available published evidence on the diagnosis, characteristics, and management of intestinal occlusion due to endometriosis. The search on PubMed retrieved 295 records, of which 158 were rejected following a review of the title and abstract. After reviewing the full text, 97 studies met the Population, Intervention, Comparator, Outcomes, and Study (PICOS) criteria and were included in the analysis. The total number of patients with bowel occlusion due to endometriosis included in the studies was 107. The occlusive endometrial foci were localized on the ileum in 38.3% of the cases, on the rectosigmoid in 34.5% of the cases, at the ileocecal junction and the appendix in 14.9% of the cases, and at the rectum in 10.2% of the cases. Only one case reported large bowel obstruction by endometriosis of the hepatic flexure of the colon extending to the transverse colon (0.9%), and in one case the obstruction was caused by an omental giant endometrioid cyst compressing the intestines. We identified six cases of postmenopausal females with acute bowel obstruction due to endometriosis. Malignant degeneration of endometriosis was also identified as a cause of intestinal occlusion. The mechanisms of obstruction include the presence of a mass in the lumen of the intestine or in the wall of the intestine, extrinsic compression, adhesions, or intussusception.

Efficacy of uncovered self-expandable metallic stent for colorectal obstruction by extracolonic malignancy

BACKGROUND

Self-expandable metallic stent (SEMS) is widely used for malignant colorectal obstruction. Recently, SEMS has been used for palliative option for colorectal obstruction caused by extracolonic malignancy (ECM).

AIM

To evaluate the efficacy of SEMS for colorectal obstruction caused by ECM, and to identify the factors associated with stent occlusion.

METHODS

Seventy-two patients who were treated with uncovered SEMS insertion for malignant colorectal obstructions caused by colorectal metastasis or peritoneal seeding of ECM at Samsung Medical Center between April 2012 to March 2016 were enrolled. We analyzed technical and clinical outcomes of stent insertion, the factors associated with stent occlusion and long term outcomes after stent insertion.

RESULTS

Technical success rate was determined as 90.3% with a clinical success rate of 87.7%. Stent occlusion developed in 28.1%, with a median duration of 51 d. Further, 81.3% with stent occlusion could be treated with secondary stent insertion. Clinical failure was observed to be related to the male sex (P = 0.020) and right colon obstruction (P = 0.017). Stent length ≤ 10 cm was found to be associated with stent occlusion (P = 0.003). Median survival time after stent insertion was 4.7 mo and 40.4% were able to receive their oncological treatments after stent insertion without surgery.

CONCLUSION

Uncovered SEMS is effective for the treatment of colorectal obstruction caused by ECM, considering life expectancy of patients with ECM.

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.

Endoscopic Management of Benign Colonic Obstruction and Pseudo-Obstruction

There are a variety of causes of intestinal obstruction, with the most common cause being malignant diseases; however, volvulus, inflammatory bowel disease or diverticulitis, radiation injury, ischemia, and pseudo-obstruction can also cause colonic obstruction. These are benign conditions; however, delayed diagnosis of acute intestinal obstruction owing to these causes can cause critical complications, such as perforation. Therefore, high levels of clinical suspicion and appropriate treatment are crucial. There are variable treatment options for colonic obstruction, and endoscopic treatment is known to be a less invasive and an effective option for such. In this article, the authors review the causes of benign colonic obstruction and pseudo-obstruction and the role of endoscopy in treating them.

Clinical effect of double coaxial self-expandable metallic stent in management of malignant colon obstruction

PURPOSE

We aimed to evaluate the clinical effectiveness and safety of double coaxial self-expandable metallic stent (DCSEMS) in management of malignant colonic obstruction as a bridge to surgery or palliation for inoperable patients.

METHODS

Between April 2006 and December 2012, 49 patients (27 males and 22 females; median age, 68 years; age range, 38-91 years) were selected to receive decompressive therapy for malignant colonic obstruction by implanting a DCSEMS. Application of DCSEMS was attempted in 49 patients under fluoroscopic guidance. The obstruction was located in the transverse colon (n=2), descending colon (n=7), sigmoid colon (n=24), rectosigmoid junction (n=6), and the rectum (n=10). The intended use of DCSEMS was as a bridge to elective surgery in 23 patients and palliation in 26 patients.

RESULTS

Clinical success, defined as >50% dilatation of the stent with subsequent symptomatic improvement, was achieved in 48 of 49 patients (98%). The stent was properly inserted in all patients. No immediate major procedure-related complications occurred. One patient in the bridge-to-surgery group had colon perforation three days after DCSEMS application. Four patients had late migrations of the double stent.

CONCLUSION

Application of DCSEMS is safe and effective in management of malignant colonic obstruction; it prevents stent migration and tumor ingrowth and lowers perforation rate during the stent application.

Stents for colorectal obstruction: Past, present, and future

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

A Novel Foam Contrast Agent Suitable for Fluoroscopic Interventional Procedure: Comparative Study of Physical Properties and Experimental Intervention in Animal Model

In fluoroscopic contrast study for interventional procedure, liquid contrast agent may be diluted in body fluid, losing its contrast effect. We developed a novel contrast agent of “foam state” to maintain contrast effect for enough time and performed a comparative study of physical properties and its usefulness in experimental intervention in animal model. The mean size of microbubble of foam contrast was 13.8 ± 3.6 µm. The viscosity was 201.0 ± 0.624 cP (centipoise) and the specific gravity was 0.616. The foam decayed slowly and it had 97.5 minutes of half-life. In terms of the sustainability in a slow flow environment, foam contrast washed out much more slowly than a conventional contrast. In experimental colonic stent placement, foam contrast revealed significantly better results than conventional contrast in procedure time, total amount of contrast usage, and the number of injections (p < 0.05). Our foam contrast has high viscosity and low specific gravity and maintains foam state for a sufficient time. Foam contrast with these properties was useful in experimental intervention in animal model. We anticipate that foam contrast may be applied to various kinds of interventional procedures.

Colorectal Stents: Current Status

A self-expandable metal stent (SEMS) is an effective and safe method for the decompression of colon obstruction. Based on recent evidence, colorectal SEMS is now recommended for the palliation of patients with colonic obstruction from incurable colorectal cancer or extracolonic malignancy and also as a bridge to surgery in those who are a high surgical risk. Prophylactic SEMS insertion in patients with no obstruction symptoms is not recommended. Most colorectal SEMS are inserted endoscopically under fluoroscopic guidance. The technical and clinical success rates of colorectal SEMS are high, and the complication rate is acceptable. Advances in this technology will make the insertion of colorectal SEMS better and may expand the indications of colorectal SEMS in the future.

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.

Oncological outcome of malignant colonic obstruction in the Dutch Stent-In 2 trial

BACKGROUND

The Stent-In 2 trial randomized patients with malignant colonic obstruction to emergency surgery or stent placement as a bridge to elective surgery. The aim of this study was to compare the oncological outcomes.

METHODS

Disease recurrence, and disease-free, disease-specific and overall survival were evaluated, including a subgroup analysis of patients with a stent- or guidewire-related perforation.

RESULTS

Of 98 patients included in the original Stent-In 2 trial, patients with benign (16) or incurable (23) disease were excluded from this study, along with a patient who had withdrawn from the trial. Of the remaining 58 patients, 32 were randomized to emergency surgery (31 resection, 1 stoma only) and 26 to stenting. Unsuccessful stenting required emergency surgery in six patients owing to wire or stent perforation. Locoregional or distant disease recurrence developed in nine of 32 patients in the emergency surgery group and 13 of 26 in the stent group. Disease-free survival was worse in the subgroup with stent- or guidewire-related perforation. Five of six patients in this subgroup developed a recurrence, compared with nine of 32 in the emergency surgery group and eight of 20 who had unperforated stenting.

CONCLUSION

Stent placement for malignant colonic obstruction was associated with a risk of recurrence in this trial, but the numbers are small. There is not enough evidence to refute the approach strongly.

REGISTRATION NUMBER

ISRCTN46462267 ( http://www.controlled-trials.com).

Enteral stents for the management of malignant colorectal obstruction

Colorectal cancer (CRC) is the 3^rd most common cancer in the United States with more than 10000 new cases diagnosed annually. Approximately 20% of patients with CRC will have distant metastasis at time of diagnosis, making them poor candidates for primary surgical resection. Similarly, 8%-25% of patients with CRC will present with bowel obstruction and will require palliative therapy. Emergent surgical decompression has a high mortality and morbidity, and often leads to a colostomy which impairs the patient’s quality of life. In the last decade, there has been an increasing use of colonic stents for palliative therapy to relieve malignant colonic obstruction. Colonic stents have been shown to be effective and safe to treat obstruction from CRC, and are now the therapy of choice in this scenario. In the setting of an acute bowel obstruction in patients with potentially resectable colon cancer, stents may be used to delay surgery and thus allow for decompression, adequate bowel preparation, and optimization of the patient’s condition for curative surgical intervention. An overall complication rate (major and minor) of up to 25% has been associated with the procedure. Long term failure of stents may result from stent migration and tumor ingrowth. In the majority of cases, repeat stenting or surgical intervention can successfully overcome these adverse effects.

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.

Enterovesical fistulae: aetiology, imaging, and management

Background and Study Objectives. Enterovesical fistula (EVF) is a devastating complication of a variety of inflammatory and neoplastic diseases. Radiological imaging plays a vital role in the diagnosis of EVF and is indispensable to gastroenterologists and surgeons for choosing the correct therapeutic option. This paper provides an overview of the diagnosis of enterovesical fistulae. The treatment of fistulae is also briefly discussed. Material and Methods. We performed a literature review by searching the Medline database for articles published from its inception until September 2013 based on clinical relevance. Electronic searches were limited to the keywords: "enterovesical fistula," "colovesical fistula" (CVF), "pelvic fistula", and "urinary fistula". Results. EVF is a rare pathology. Diverticulitis is the commonest aetiology. Over two-thirds of affected patients describe pathognomonic features of pneumaturia, fecaluria, and recurrent urinary tract infections. Computed tomography is the modality of choice for the diagnosis of enterovesical fistulae as not only does it detect a fistula, but it also provides information about the surrounding anatomical structures. Conclusions. In the vast majority of cases, this condition is diagnosed because of unremitting urinary symptoms after gastroenterologist follow-up procedures for a diverticulitis or bowel inflammatory disease. Computed tomography is the most sensitive test for enterovesical fistula.

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.

Preoperative colonoscopy for detection of synchronous neoplasms after insertion of self-expandable metal stents in occlusive colorectal cancer: comparison of covered and uncovered stents

Background/Aims

In patients with occlusive colorectal cancers, a complete preoperative evaluation of the colon proximal to the obstruction is often impossible. We aimed to evaluate the feasibility of preoperative colonoscopy after stent placement and to determine whether the success rate of colonoscopy differs between covered and uncovered stents.

Methods

Seventy-three patients with malignant colorectal obstruction were enrolled prospectively. In patients with a resectable cancer, a preoperative colonoscopy was performed after insertion of a self-expandable metal stent (SEMS). The success rate of complete preoperative colonoscopy was compared between covered and uncovered stents.

Results

Forty-five of 73 patients who underwent stent placement had a resectable cancer (61.6%). A complete preoperative colonoscopy was possible in 40 of 45 patients (88.9%). The success rate of complete preoperative colonoscopy was significantly lower in the covered-stent group when the obstructing mass lesion was located in the sigmoid colon (p=0.024). Synchronous cancer was detected in one patient (2.2%). Stent migration was observed in four patients with a covered stent.

Conclusions

A preoperative complete colonoscopy after SEMS placement was feasible and safe in most patients with malignant colorectal obstruction. Uncovered stents seem to have more advantages than covered stents in preoperative colonoscopy proximal to the obstruction.

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.

Endoprosthetic management of refractory ileocolonic anastomotic strictures after resection for Crohn's disease: report of nine-year follow-up and review of the literature

BACKGROUND

The role of endoluminal stenting in benign obstruction, especially for Crohn's disease (CD), is controversial, with limited data and widely disparate outcomes. The purpose of this study was to determine the long-term efficacy and safety of this technology in the treatment of fibrostenotic CD and to review the existing literature on this topic.

METHODS

We undertook a retrospective review of all patients undergoing endoluminal stenting for CD strictures at our institution from 2001 to 2010. Outcome measures included technical success, clinical improvement, duration of stent and luminal patency, and need for re-intervention.

RESULTS

Five patients underwent this procedure with a 100% rate of technical and an 80% rate of clinical success. Mean follow-up was 28 months (range 3 weeks to 109 months) and mean long-term luminal patency was 34.8 months (range 4.5-109 months). There was one complication involving reobstruction which required surgical intervention and no mortalities.

CONCLUSIONS

Endoluminal stenting of CD strictures is a safe and effective alternative to surgery which can provide lasting benefit in select patients. Further studies are necessary to clarify the full impact of this technology on long-term management of this complex disease.

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.

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.

Review article: palliative care in gynecologic oncology

Patients with advanced gynecologic malignancies have a multitude of symptoms; pain, nausea, and vomiting, constipation, anorexia, diarrhea, dyspnea, as well as symptoms resulting from intestinal obstruction, hypercalcemia, ascites, and/or ureteral obstruction. Pain is best addressed through a multimodal approach. The optimum palliative management of end-stage malignant intestinal obstruction remains controversial, with no clear guidelines governing the choice of surgical versus medical management. Patient selection for palliative surgery, therefore, should be highly individualized because only carefully selected candidates may derive real benefit from such surgeries. There remains a real need for more emphasis on palliative care education in training programs.

[Two cases of colonic obstruction after acute pancreatitis]

Several forms of colonic complications are rarely observed during the clinical course of acute pancreatitis, and potentially fatal in some cases. Colonic lesions associated with acute pancreatitis can be divided into several groups from a pathogenic point of view. Possible pathogenesis includes: 1) spread of pancreatic enzymes through the retroperitoneum to mesocolon, causing pericolitis, 2) external inflammatory compression by mesocolic mass secondary to necrosis of fatty tissue, and 3) hypotension due to shock, and thrombosis of mesenteric arteries. These might lead to colonic infarction, fistula formation, perforation, and obstruction during follow-up. We report two cases of colonic obstruction following acute pancreatitis with possible different mechanisms and review Korean cases. One patient developed colonic obstruction due to severe necrotizing pancreatitis, possibly as a result of pericolitis, and the other developed stenosis as a result of ischemic colitis induced by acute pancreatitis.

Oncologic outcomes of self-expanding metallic stent insertion as a bridge to surgery in the management of left-sided colon cancer obstruction: comparison with nonobstructing elective surgery

BACKGROUND

Self-expanding metallic stents (SEMS) have been used as a bridge to surgery in patients with obstruction by colorectal cancer, but the oncologic safety of this technique has not yet been established. The aim of the present study was to compare the outcomes of bridge to surgery after SEMS insertion and nonobstructing elective surgery.

METHODS

Between October 1999 and July 2007, 35 patients who had left-sided colon malignancy obstruction and underwent surgical resection after SEMS insertion (group A) were matched to 350 patients who underwent elective surgery for nonobstructing left-sided colon cancer based on stage II, III, and IV malignancies according to the 2001 American Joint Committee on Cancer (group B). Group B was randomly extracted from the colorectal database of our institute. The two groups were compared for clinicopathologic variables, complications, and survival rate.

RESULTS

There were no significant differences in clinicopathologic variables between group A and group B. However, the stoma formation rate was statistically different between the two groups (p = 0.003). Self-expanding metallic stent insertion had an adverse effect on the 5-year overall survival rate (A vs. B, 38.4% vs. 65.6%, respectively; p = 0.025) and the 5-year disease-free survival rate (A vs. B, 48.3% vs. 75.5%, respectively; p = 0.024).

CONCLUSIONS

These data show that insertion of SEMS as a bridge to surgery in the management of left-sided colon cancer obstruction is possibly associated with adverse oncologic outcomes compared with nonobstructing elective surgery, but it is unclear what magnitude of this effect is related to the underlying obstruction rather than to the SEMS.

Dual-design expandable colorectal stent for malignant colorectal obstruction: comparison of flared ends and bent ends

OBJECTIVE

The purpose of this study was to compare, focusing on colonic perforation and stent migration, the clinical safety and efficacy of dual-design expandable colorectal stents with flared ends with those of stents with bent ends in the treatment of patients with malignant colorectal obstruction.

SUBJECTS AND METHODS

A total of 122 patients with malignant colorectal obstruction underwent implantation of dual-design stents with flared (n = 69) or bent (n = 53) ends.

RESULTS

Stent placement was technically successful in 116 of 122 patients (95.1%), 65 of 69 patients (94.2%) with flared-end stents and 51 of 53 patients (96.2%) with bent-end stents (p > 0.05). Clinical success was achieved within 2 days in 61 of 65 patients (93.8%) with bent-end stents and in 46 of 51 patients (90.2%) with flared-end stents (p > 0.05). Complications included seven cases of colonic perforation (6%), seven cases of stent migration (6%), three cases of tumor overgrowth (2.6%), four cases of severe rectal pain (3.4%), and four cases of bleeding (3.4%). There were no significant differences between the rates of colonic perforation and stent migration in the two groups (6.2% vs 5.9%), and the overall complication rates were similar (p > 0.05).

CONCLUSION

Dual-design expandable colorectal stents with flared ends and those with bent ends are equally safe and effective, having similar perforation and migration rates.

Effectiveness of stent placement for palliative treatment in malignant colorectal obstruction and predictive factors for stent occlusion

BACKGROUND

Self-expandable metallic stent (SEMS) for malignant colorectal obstruction is widely used in palliative treatment and as an alternative to surgery. The aims of this study are to evaluate the effectiveness of stent placement for palliative treatment and to identify the predictive factors associated with stent occlusion.

METHODS

A retrospective analysis was performed in 55 patients who had undergone placement of an uncovered SEMS from February 2004 to April 2007 for palliative treatment of malignant colorectal obstruction with metastatic or locally advanced cancer that was surgically unresectable. We analyzed the technical and clinical outcomes of stent placement, complications related to the procedure, stent patency rate, and predictive factors associated with stent occlusion.

RESULTS

The causes of colorectal obstruction before stent placement were primary colorectal cancer in 42 patients and noncolorectal extrinsic cancer in 13 patients. The initial technical success rate was 98.2%, and the clinical success rate was 94.4%. Complications occurred in 17 patients (30.9%). These included stent occlusion (n = 8), migration (n = 6), bowel perforation (n = 1), stent distortion (n = 1), and fistula formation (n = 1). The mean and median stent patency periods were 184 days [95% confidence interval (CI), 137-230 days] and 141 days (95% CI, 69-213 days), respectively. The degree of expansion 48 h after stent placement was significantly better in the nonocclusion group than in the stent occlusion group. In the multivariate Cox proportional hazard model, insufficient stent expansion (<70%) 48 h after stent placement was significantly associated with an increase in stent occlusion during the follow-up period (odds ratio, 12.55; p = 0.002).

CONCLUSIONS

Uncovered SEMS placement is an effective palliative treatment for malignant colorectal obstruction. The degree of stent expansion 48 h after stent placement is significantly associated with the maintenance of stent patency and is a predictive factor for stent occlusion.

Clinical outcomes and patency of self-expanding metal stents in patients with malignant colorectal obstruction: a prospective single center study

BACKGROUNDS AND AIMS

Self-expanding metal stents (SEMS) have been used as a palliative treatment for malignant colorectal obstruction. However, the reports about primary stent patency rate and associated factors have been limited. This study was performed to evaluate clinical outcomes and factors associated with long-term complications and patency of SEMS in patients with malignant colorectal obstruction.

MATERIALS AND METHODS

Patients who underwent palliative endoscopic placement with uncovered SEMS for a malignant colorectal obstruction were prospectively enrolled at Seoul National University Hospital between April 2005 and August 2007.

RESULTS

Forty-nine patients underwent 51 SEMS placements. Obstruction sites were rectum in 15 patients (30.6%), descending or sigmoid colon in 25 (51.0%), and transverse colon in nine (18.4%), respectively. The causes of obstruction were colorectal cancer in 36 patients (73.5%), direct invasion of gastric cancer in seven (14.3%) and others in six (12.2%). Technical success was achieved in 100% and clinical success in 86%, and there was one procedure-related perforation. Re-obstruction and migration occurred in 16% and 6%, respectively, during mean follow-up period of 331 days. Median stent patency duration was 204 days, and patency rates at 30, 90, and 180 days were 91.2%, 81.0%, and 53.3%, respectively, which was not associated with patient demographics, site of obstruction, or palliative chemotherapy.

CONCLUSION

Endoscopic SEMS placement is a safe and effective palliative treatment for malignant colorectal obstruction, and overall long-term complication and patency were favorable irrespective of the palliative chemotherapy.

Endoscopic stenting-Where are we now and where can we go?

Self expanding metal stents (SEMS) play an important role in the management of malignant obstructing lesions in the gastrointestinal tract. Traditionally, they have been used for palliation in malignant gastric outlet and colonic obstruction and esophageal malignancy. The development of the polyflex stent, which is a removable self expanding plastic stent, allows temporary stent insertion for benign esophageal disease and possibly for patients undergoing neoadjuvant chemotherapy prior to esophagectomy. Potential complications of SEMS insertion include perforation, tumour overgrowth or ingrowth, and stent migration. Newer stents are being developed with the aim of increasing technical and clinical success rates, while reducing complication rates. Other areas of development include biodegradable stents for benign disease and radioactive or drug-eluting stents for malignant disease. It is hoped that, in the future, newer stents will improve our management of these difficult conditions and, possibly, provide prognostic as well as symptomatic benefit in the setting of malignant obstruction.

Clinical outcomes and patency of self-expanding metal stents in patients with malignant upper gastrointestinal obstruction

This study was performed to evaluate clinical outcomes and factors associated with patency of self-expanding metal stents (SEMS) in patients with malignant upper gastrointestinal (UGI) obstruction. In 83 patients with malignant UGI obstruction, 118 SEMS placements were performed. Obstruction sites were esophagus/gastro-esophageal junction (GEJ) and gastric outlet (GO) in 41 and 42 patients, respectively. Technical success was achieved in 99.2% and clinical success in 90.5%, with no procedure-related complications. Re-obstruction and migration occurred in 38.1% during a mean follow-up of 137 days; both occurred significantly more often with GO than esophageal/GEJ obstruction (49.2% vs 23.9%). Patency rates of esophageal/GEJ obstruction were 93.5, 78.1 and 67.0% at 30, 90 and 180 days, respectively, and were significantly higher than those of GO obstruction-71.7, 51.8 and 32.5%. Palliative chemotherapy or radiation therapy was not associated with stent patency. Endoscopic SEMS placement is a safe and effective palliative treatment for malignant UGI obstruction, and complications or stent patency differed according to obstruction site.

Expandable metal stent placement for benign colorectal obstruction: outcomes for 23 cases

BACKGROUND

Self-expanding metal stents (SEMS) are an established treatment for palliation of malignant colorectal strictures and as a bridge to surgery for acute malignant colonic obstruction. Patients with benign colonic strictures may benefit from stent placement, but little data exist for this indication.

METHODS

All cases of colonic stent placement identified from a prospectively collected gastrointestinal database from April 1999 to August 2006 were reviewed. During the study period, 23 patients with benign obstructive disease underwent endoscopic SEMS placement. The etiologies of the stricture were diverticular/inflammatory (n = 16), postsurgical anastomotic (n = 3), radiation-induced (n = 3), and Crohn's (n = 1) disease. All strictures were located in the left colon. Five patients had an associated colonic fistula. Uncovered Enteral Wallstents or Ultraflex Precision Colonic stents (Boston Scientific) were endoscopically placed in all but one patient.

RESULTS

Stent placement was technically successful for all 23 patients, and obstruction was relieved for 22 patients (95%). Major complications occurred in 38% of the patients including migration (n = 2), reobstruction (n = 4), and perforation (n = 2). Of these major complications, 87% occurred after 7 days. Four patients did not undergo an operation. Of the 19 patients who underwent planned surgical resection, 16 were successfully decompressed and converted from an emergent operation to an elective one with a median time to surgical resection of 12 days (range, 2 days to 18 months). Surgery was delayed more than 30 days after stent placement for six of these patients. Of the 19 patients who underwent a colectomy, 8 (42%) did not need a stoma after stent insertion.

CONCLUSIONS

SEMS can effectively decompress high-grade, benign colonic obstruction, thereby allowing elective surgery. The use of SEMS can offer medium-term symptom relief for benign colorectal strictures, but this approach is associated with a high rate of delayed complications. Thus, if elective surgery is planned, data from this small study suggest that it should be performed within 7 days of stent placement.

Comparison of Wallstent and Ultraflex stents for palliation of malignant left-sided colon obstruction: a retrospective, case-matched analysis

BACKGROUND

Self-expandable metal stents (SEMSs) are accepted palliation for malignant colon obstruction. Outcomes of different stent types is unknown.

OBJECTIVE

Our purpose was to compare outcomes after palliative placement of the Enteral Wallstent (EW) and the Precision Colonic Ultraflex (PCU) stent.

DESIGN

Retrospective study of all SEMS placement during a 7-year period.

SETTING

Tertiary care academic medical center.

PATIENTS

Malignant left-sided colon obstruction in which through-the-scope (TTS) or non-TTS stent placement was possible.

MAIN OUTCOME MEASUREMENTS

Technical and clinical success rates, stent-related complications, reintervention.

RESULTS

Demographics, degree, site, and cause of obstruction were comparable. Technical difficulties were more frequent with EW than PCU (16% vs 9%, P not significant), insufficient stent expansion and stent misplacement being most common. Relief of obstruction occurred in all patients when placement was technically successful. Mean follow-up was 93 days (range 7-691 days). Early (<7 days) stent occlusion (6% vs 0%, P not significant) and migration (4% vs 0%, P not significant) occurred more frequently in the EW group. Self-limited hematochezia was more common with PCU (20% vs 2%, P = .002). Delayed complications (perforation, stent occlusion, migration, and erosion) occurred significantly more often in the EW group (38% vs 20%). Reintervention was needed more frequently for EW, endoscopic (40% vs 17%, P = .01) and operative (46% vs 26%, P = .03).

CONCLUSIONS

Enteral Wallstents and Precision Ultraflex Colonic stents adequately relieve colonic obstruction. Stent dysfunction, stent-related complications, and need for reintervention are higher after EW placement. Precision Colonic Ultraflex stents appear better suited for palliation of left-sided malignant colon obstruction.

Palliation of colorectal cancer

Patients with advanced incurable colorectal cancer (CRC) face a grim prognosis. The goal of palliative intervention is directed at alleviating disease-related symptoms and improving quality of life. The provision of optimal palliative care for these patients is a compound and demanding process. This dilemma becomes more challenging when patients with advanced metastatic colorectal disease present with an incurable and asymptomatic primary lesion. Treatment options are numerous and include a variety of surgical and nonsurgical interventions. Most data regarding the role of surgery in palliation of CRC are from retrospective, nonrandomized case series. Surgical resection may provide good palliation of symptoms and prevent future tumor-related complications. Metal stents are also able to provide good palliative relief of obstruction and should be used when appropriate. The best palliative care will often require a multidisciplinary approach that involves input from surgical and nonsurgical teams, where treatment plans will be made in accordance with the wishes of the patient and family with a goal of decreasing morbidity and a focus on quality of life.

Current management strategies for ovarian cancer

Epithelial ovarian cancer originates in the layer of cells that covers the surface of the ovaries. The disease spreads readily throughout the peritoneal cavity and to the lymphatics, often before causing symptoms. Of the cancers unique to women, ovarian cancer has the highest mortality rate. Most women are diagnosed as having advanced stage disease, and efforts to develop new screening approaches for ovarian cancer are a high priority. Optimal treatment of ovarian cancer begins with optimal cytoreductive surgery followed by combination chemotherapy. Ovarian cancer, even in advanced stages, is sensitive to a variety of chemotherapeutics. Although improved chemotherapy has increased 5-year survival rates, overall survival gains have been limited because of our inability to eradicate all disease. Technologic advances that allow us to examine the molecular machinery that drives ovarian cancer cells have helped to identify numerous therapeutic targets within these cells. In this review, we provide an overview of ovarian cancer with particular emphasis on recent advances in operative management and systemic therapies.

Metal stents for malignant colorectal obstruction

Malignant obstruction of the colon occurs in 7-25% of patients with colorectal cancer. As emergency laparotomy is reported to have relatively high morbidity and mortality rate, there is a need for alternative procedures with reduced complication rates. Over the last decade colorectal stenting has been reported as an alternative endoscopic method to relieve acute colonic obstruction. With the availability of more sophisticated stents and stent delivery systems, this approach has been used as a palliative method and as a pre-operative bridge to facilitate one-stage surgical resection of primary colonic tumors. Technical and clinical successes have been reported in 80-100% of treated patients. Distal lesions are more common and theoretically easier to stent although lesions within the ascending colon have been successfully managed. Minor complications include transient anorectal pain, tenesmus and rectal bleeding. However, stent migration and colonic perforation are also well recognized. Despite the fact that no randomized controlled studies have yet been performed, literature data show that colonic stenting is a safe and effective procedure and can reduce costs, avoiding the need for colostomy and improving the quality of life of patients with advanced disease.

Acute colonic obstruction

Acute colonic obstruction is a medical emergency because of the potential for bowel ischemia, perforation, and sepsis with peritonitis if not rapidly and appropriately treated. There are numerous causes of acute colonic obstruction, which must be differentiated from colonic pseudo-obstruction, which also is considered a medical emergency. Management options include medical therapy, surgical therapy, endoscopic therapy, and interventional radiologic therapy. Self-expandable metal stents (SEMS) have gained acceptance for alleviating acute malignant colonic obstruction and in some situations for preoperative relief of acute benign colonic obstruction. This article reviews the approach to the patient who has acute colonic obstruction.

Minimizing endoscopic complications: endoluminal stents

Almost all endoluminal stents used by gastroenterologists in the United States are self-expandable metal stents, and they are placed most commonly for relief of malignant luminal obstruction. Recently, a plastic self-expandable stent was approved for treating refractory benign esophageal strictures. Endoluminal stent placement is associated with myriad of complications. Some of these complications can be avoided or minimized by the endoscopist, whereas others are beyond the endoscopist's control. This article covers the various complications that can occur following self-expandable stent placement and provides recommendations on how to minimize these complications.

Advances in gastrointestinal endoscopic techniques

An increasing number of techniques for endoscopic diagnosis and treatment is being described. Endoscopic surgeons should be familiar with these techniques. Although many of the diagnostic techniques, other than marking, do not have widespread clinical application, the therapeutic techniques that were described in this article are being used successfully in increasing numbers of appropriately selected patients. Additional experience and technologic advances will refine the endoscopic therapy that is available to patients with colorectal diseases.

Effects of 5-fluorouracil adjuvant treatment of colon cancer

Since the late 1980s and early 1990s, 5-fluorouracil-based chemotherapy has been the standard adjuvant treatment for Stage III colon cancer. After the initial introduction of 5-fluorouracil in standard treatment protocols, several changes have been made based on results of randomized studies on various treatment regimens, including new cytotoxic agents. In Stage II patients, the role of adjuvant chemotherapy is debatable. However, there might be a role for adjuvant treatment in certain high-risk patients. Following a search of the Medline database, the results of randomized studies on 5-fluorouracil-based adjuvant therapy are reviewed, and future therapeutic options are discussed.