Preoperative colonoscopy after self-expandable metallic stent placement in patients with acute neoplastic colon obstruction

A predictive model for colorectal cancer complicated with intestinal obstruction based on specific inflammation score

PURPOSE

Inflammatory factors play an important role in the onset and progression of colorectal cancer (CRC). This study aimed to develop and validate a novel scoring system that utilizes specific inflammatory factor indicators to predict intestinal obstruction in CRC patients.

METHODS

This study conducted a retrospective analysis of 1,470 CRC patients who underwent surgical resection between January 2013 and July 2018. These patients were randomly allocated to the training group (n = 1060) and the validation group (n = 410). Univariate and multivariate logistic regression analyses were performed to identify independent predictive factors for intestinal obstruction. The CRC peculiar inflammation score (CPIS), comprising lymphocyte-to-monocyte ratio (LMR), prognostic nutrition index (PNI), and alanine transaminase-to-lymphocyte ratio index (ALRI) scores, was significantly associated with the occurrence of intestinal obstruction. A nomogram combining CPIS with other clinical features was developed to predict this occurrence. Model accuracy was assessed by determining the area under the receiver operating characteristic (ROC) curve (AUC).

RESULTS

The CPIS generated by multi-factor logistic regression was as follows: - 1.576 × LMR - 0.067 × PNI + 0.018 × ALRI. Using CPIS cutoff values of 50% (- 7.188) and 85% (- 6.144), three predictive groups were established. Patients with a high CPIS had a significantly higher risk of intestinal obstruction than those with a low CPIS (odds ratio [OR]: 10.0, confidence interval [CI]: 5.85-17.08, P < 0.001). The predictive nomogram demonstrated good calibration and discrimination abilities. The AUC of the ROC curve for the obstruction nomogram was 0.813 (95% CI: 0.777-0.850) in the training set and 0.806 (95% CI: 0.752-0.860) in the validation set. The calibration curve exhibited neither bias nor high credibility. Decision curve analysis indicated the utility of this predictive model.

CONCLUSION

CRC-associated intestinal obstruction is closely linked to inflammatory markers in patients. CPIS is a CRC-specific inflammatory predictive score based on a combination of inflammatory-related indicators. A high CPIS serves as a strong indicator of intestinal obstruction. Its integration with other clinical factors and preoperative inflammatory-specific indicators significantly enhances the diagnosis and treatment of CRC patients with intestinal obstruction.

Colon cancer: the 2023 Korean clinical practice guidelines for diagnosis and treatment

Colorectal cancer is the third most common cancer in Korea and the third leading cause of death from cancer. Treatment outcomes for colon cancer are steadily improving due to national health screening programs with advances in diagnostic methods, surgical techniques, and therapeutic agents.. The Korea Colon Cancer Multidisciplinary (KCCM) Committee intends to provide professionals who treat colon cancer with the most up-to-date, evidence-based practice guidelines to improve outcomes and help them make decisions that reflect their patients' values and preferences. These guidelines have been established by consensus reached by the KCCM Guideline Committee based on a systematic literature review and evidence synthesis and by considering the national health insurance system in real clinical practice settings. Each recommendation is presented with a recommendation strength and level of evidence based on the consensus of the committee.

The optimal surgery timing after stenting in colorectal cancer patients with malignant obstruction: additionally compared with emergency surgery

BACKGROUND

This study aimed to determine short-term and long-term outcomes according to time intervals after stenting and compared them with those of emergency surgery (ES) in colorectal cancer (CRC) with malignant obstruction.

METHODS

CRC with malignant obstructions was reviewed retrospectively between January 2008 and July 2018. Of a total of 539 patients who visited the emergency room and underwent ES, 133 were enrolled in the ES group. Of a total of 567 patients who initially received stenting and subsequently underwent elective surgery, 220 were enrolled in the SEMS group. The interval between SEMS placement and elective surgery was classified as < 11 days, 11-17 days, and > 17 days.

RESULTS

For those who received SEMS (n = 220), those with a time interval of 11-17 days (n = 97) had fewer hospital days than those with a time interval of < 11 days (n = 68) (8 days vs. 15 days) and less stoma formation than those with a time interval of > 17 days (n = 55) (1.0% vs. 14.6%). Multivariable analysis revealed a decreased risk of death for the group with a time interval of 11-17 days (20.6%) compared to the ES group (31.6%) (hazard ratio: 0.48; 95% confidence interval: 0.24-0.97). Disease-free survival was comparable between the SEMS and ES groups regardless of the time interval (log-rank p = 0.52).

CONCLUSIONS

The time interval of 11-17 days after stenting to elective surgery appeared to be associated with the most favorable outcomes.

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

INTRODUCTION

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

AREA COVERED

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

EXPERT OPINION

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

Preoperative diagnosis of obstructive colitis in colorectal cancer patients who underwent self-expandable metallic stent insertion as a bridge to surgery

PURPOSE

Obstructive colitis (OC) is a risk factor of anastomotic leakage in colorectal cancer resection. We aimed to clarify the relationship between the severity of OC and clinicopathological findings and to detect predictive factors of OC.

METHODS

We retrospectively reviewed 43 cases of colectomy after self-expandable metallic stent placement for left-sided colorectal cancer. Preoperative diagnosis of OC was made by multiple modalities (initial computed tomography (CT), presurgical CT, and colonoscopy). We classified OC macroscopically in resected specimens into five groups (Grade 0: none, 1: mild [mild edema], 2: moderate [severe edema, redness, erosion], 3: severe [ulceration, bleeding], 4: very severe [necrosis, perforation]), and investigated the relationship between the preoperative assessment, surgical findings and the severity of OC.

RESULTS

OC of Grade 2 or more (53.5%) was significantly correlated with severe edema in initial CT. There was no significant correlation between OC and anastomosis rate. The creation of covering stoma was significantly higher in the Grade 2 or more OC group. No leakage was observed in either group.

CONCLUSIONS

Initial CT may be most useful for prediction of OC. It is important to make a preoperative diagnosis of OC by combining multiple modalities, which enables to determine the appropriate location for resection, anastomosis, and construction of a covering stoma.

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.

The Value of Haematological Parameters and Tumour Markers in the Prediction of Intestinal Obstruction in 1474 Chinese Colorectal Cancer Patients

Intestinal obstruction, a life-threatening problem, often occurs in patients with advanced colorectal cancer (CRC). However, the cause of obstruction is still unknown. Very few prediction models for intestinal obstruction in CRC exist, and their results are unreliable. Therefore, we investigated whether preoperative serum tumour markers (STMs) combined with haematological and biochemical markers could be used as predictors. We retrospectively analysed 1474 patients with CRC who underwent radical resection after admission. Several clinical features, STMs, and serum biochemical and haematological indicators were analysed. Predictors of intestinal obstruction were analysed with univariate and multivariate logistic regression. The accuracy of the multivariate predictors of obstruction was measured by the area under the receiver operating characteristic (ROC) curve (AUC). The Kaplan-Meier method was used to create survival curves. Obstruction was found more in males (62.18%), never-smokers (73.95%), the left colon (54.20%), the tumour diameter > 4.5 cm (55.88%), high differentiation (89.50%), and negative nerve invasion (70.17%). The serum tumour markers (STMs) and peripheral blood routine indexes (PBRI) were significantly associated with obstructive status (p < 0.05). Multivariate analysis demonstrated that the neutrophil and lymphocyte counts, carcinoembryonic antigen, carbohydrate antigen 19-9, carbohydrate antigen 125, albumin, alkaline phosphatase, gamma-glutamyl transpeptidase, total protein, and neutrophil-to-lymphocyte ratio were predictors of intestinal obstruction (p < 0.05). The AUC for the curve with all the eight factors was 0.715 (95% confidence interval: 0.673-0.758). The STMs and PBRI were related to the obstruction status of the patients, and they could be used in combination with other clinical factors to significantly improve diagnosis and management of intestinal obstruction in CRC 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.

Long-term tumour outcomes of self-expanding metal stents as 'bridge to surgery' for the treatment of colorectal cancer with malignant obstruction: a systematic review and meta-analysis

PURPOSE

To explore the long-term oncological results of self-expanding metal stents (SEMS) as a surgical transition compared with those of simple emergency surgery.

METHODS

A systematic review of studies involving long-term tumour outcomes comparing SEMS with emergency surgery was conducted. All studies included information on 3-year and 5-year survival rates, 3-year and 5-year disease-free survival (DFS) rates, and local and overall recurrence rates; the results were expressed as odds ratios.

RESULTS

Overall, 24 articles and 2508 patients were included, including 5 randomised controlled trials, 3 prospective studies, and 16 retrospective studies. The 3-year survival rate (odds ratio (OR) = 0.88, 95% confidence interval (CI) 0.69-1.12, P = 0.05), 5-year survival rate (OR = 0.91, 95% CI 0.70-1.17, P = 0.67), 3-year DFS rate (OR = 1.14, 95% CI 0.91-1.42, P = 0.65), 5-year DFS rate (OR = 1.35, 95% CI 0.91-2.02, P = 0.17), overall recurrence rate (OR 1.04, 95% CI 0.77-1.41, P = 0.14), and local recurrence rate (OR 1.37, 95% CI 0.84-2.23, P = 0.92) were determined. There was no significant difference between the randomised and observational studies in the subgroup analysis, and the 5-year survival rate was higher in studies with a stent placement success rate of ≥ 95%.

CONCLUSION

SEMS implantation was a viable alternative in malignant left colon obstruction as a transition to surgery; its long-term survival results, including 5-year DFS and overall survival, were equivalent to those of emergent surgery.

Successful single-stage laparoscopic surgery using a preoperative self-expanding metallic stent in patients with obstructive colorectal cancer

INTRODUCTION

Although a self-expanding metallic stent (SEMS) or a transnasal or transanal decompression tube is sometimes used as a bridge to surgery in patients with obstructive colorectal cancer, the optimal decompression procedure to achieve successful laparoscopic surgery remains unclear.

METHODS

Forty-two patients with obstructive colorectal cancer who were preoperatively decompressed by using SEMS (the SEMS group, n = 20) or a decompression tube (the DT group, n = 22) between January 2010 and February 2017 were included in this retrospective study.

RESULTS

In the SEMS group, 20 patients (100%) were able to eat and 17 patients (85%) were able to undergo total colonoscopy preoperatively, but no patients could do so in the DT group (P < 0.01 and P < 0.01, respectively). The serum albumin level increased in the time between admission and just before surgery in five patients in the SEMS groups (25%), whereas it decreased in all patients in the DT group (P = 0.037). Laparoscopic surgery was performed more frequently in the SEMS groups (19 patients, 95%) than in the DT group (13 patients, 59.1%) (P = 0.018). Primary anastomosis without stoma was also achieved more frequently in the SEMS groups (19 patients, 95%) than in the DT group (15 patients, 68.2%) (P = 0.047). Anastomotic leakage did not occur in the SEMS group, but it did occur in one patient in the DT group. The recurrence-free survival rate did not differ between the groups (median follow-up period: 21 months).

CONCLUSION

In patients with obstructive colorectal cancer, SEMS appears to be more effective than a decompression tube as a preoperative treatment to achieve successful laparoscopic resection without stoma.

Efficacy of 18-fluoro deoxy glucose-positron emission tomography computed tomography for the detection of colonic neoplasia proximal to obstructing colorectal cancer

Identification of secondary colonic neoplasia proximal to obstructing colorectal cancer is essential for determining the range of colorectal resection.We examined the accuracy of 18-fluoro deoxy glucose-positron emission tomography (FDG-PET) for detection of colonic neoplasia.We recruited patients with obstructing colorectal cancer from our registry. Preoperative FDG-PET was performed, and the detection rate for colonic neoplasia was estimated. Preoperative colonoscopy or postoperative colonoscopy within a year after operation was employed as the indexed standard.Ninety-three patients were included in this study. Colonic neoplasia proximal to obstruction was confirmed in 83 cases. The sensitivity and positive predictive value of FDG-PET were 25.3% and 77.8%, respectively. The sensitivity was higher in larger lesions (3.2% for <5 mm, 29.4% for 6-10 mm, 45.5% for 11-20 mm, and 71.4% for >21 mm) and in higher pathological grade lesions (14.6% for low-grade adenoma, 38.5% for high-grade adenoma, 66.7% for carcinoma in situ, and 100% for invasive carcinoma). The round shape in PET images was a predictor for neoplasia, with an area under the curve of 0.75293 at an aspect ratio of 1.70.FDG-PET should be used as a screening modality for invasive colorectal cancer (CRC) proximal to obstructing colorectal cancer.

Using stents in the management of malignant bowel obstruction: the current situation and future progress

The use of self-expanding metal stents (SEMS) has been considered an effective and safe alternative to emergency surgery as bridge to surgery or for palliation in advanced colorectal cancer even though more recent data have raised concerns on both early and long-term outcomes when patients are treated with bridge to surgery indications. Areas covered: A comprehensive literature review of articles on endoscopic management of malignant bowel obstruction was performed. Indication, technique, outcomes, benefits and risks of these treatments in acute malignant colonic obstruction were reviewed. The clinical effectiveness and safety of SEMS in obstructive colorectal cancer, as bridge to surgery or for palliation compared to surgery, is discussed. Expert commentary: SEMS placement, when performed in tertiary level center with appropriate expertise in colorectal stenting, may have several advantages over surgery avoiding the potential for surgical morbidity in a typically frail group of patients even though these advantages are to be carefully balanced over the risk of life-threatening, stent-related complications.

Elective Surgery After Endoscopic Self-Expandable Metallic Stent Placement for Patients With Obstructive Colon Cancer: Preoperative Systemic Evaluation and Management

One-stage curative surgical resection for obstructive colon cancer is challenging. Self-expandable metallic stents (SEMSs) are known as an alternative treatment used to avoid emergency operation. We aimed to evaluate the significance of SEMS placement as a bridge to surgery and the surgical outcomes of the elective operation. A consecutive 20 patients with obstructive colon cancer undergoing SEMS placement between June 2014 and February 2016 were included. The technical outcomes of the SEMS placement, surgical procedures, and surgical outcomes were evaluated retrospectively. Among them, 2 patients were treated with a SEMS palliatively, and the others were treated with a SEMS as a bridge to surgery. All SEMS were placed successfully at the first attempt, and there was no SEMS-related complication. Before surgery, all patients could be diagnosed histologically, and they were evaluated systemically including proximal colon or distant metastasis. The median time to operation after SEMS placement was 14 days (range 9–20 days). Seven of the 18 patients underwent a laparoscopic colectomy without conversion to laparotomy. All patients with stage II or III colon cancer underwent curative surgery, and 2 patients with stage IV colon cancer underwent a one-stage resection of the primary colon cancer and simultaneous liver metastasis after the evaluation of hepatic functional reserve. There was no mortality or SEMS-related complication in the perioperative period. SEMS placement as a bridge to surgery for patients with obstructive colon cancer is safe and effective to provide an adequate amount of time for a preoperative systemic management and evaluation.

Three cases of endoscopic resection for synchronous early colon cancers after self-expandable metallic stent placement for obstructive colon cancer

The feasibility of endoscopic resection for synchronous early colon cancer after placement of self-expandable metallic stents (SEMS) for malignant colorectal obstruction is unknown. Herein we evaluated 3 cases of endoscopic resection for synchronous early colorectal cancers after SEMS placement. Patient 1 was an 82-year-old man with obstructive sigmoid colon cancer. We curatively treated the synchronous descending colon cancer with endoscopic submucosal dissection (ESD) and the rectal cancer with endoscopic mucosal resection (EMR) after SEMS placement. This is the first reported case of a successful ESD for synchronous early colon cancer via the use of a colonic stent. Patient 2 was an 81-year-old man with obstructive ascending colon cancer. We resected the synchronous transverse colon cancer via ESD. Histologic findings indicated that the carcinoma cells had invaded the submucosal layer. Therefore, we immediately performed expanded right-hemicolectomy. Patient 3 was an 81-year-old man with obstructive sigmoid colon cancer. We curatively treated the synchronous transverse colon cancer with EMR after SEMS placement. There were no complications associated with the endoscopic treatments in any of the cases. Our results indicate that preoperative endoscopic resection combined with the ESD technique for synchronous colorectal cancer after SEMS placement could be effective as a surgical strategy for patients with malignant colorectal obstruction.

Comparison between metallic stent and transanal decompression tube for malignant large-bowel obstruction

BACKGROUND

The short-term safety and efficacy of a self-expandable metallic colonic stent (SEMS) insertion followed by elective surgery, "bridge to surgery (BTS)", for malignant large-bowel obstruction (MLBO) have been well described comparing with emergency surgery. The aim of this study was to compare short-term outcomes of endoscopic decompression using a SEMS versus a transanal decompression tube (TDT).

MATERIALS AND METHODS

From January 2005 to November 2014, a total of 101 patients with MLBO underwent surgery at our single institution were retrospectively identified. Among them, 73 patients who underwent preoperative complete insertion of a decompression device (TDT, n = 45; SEMS, n = 28) were finally included in this study. Six patients with incomplete insertion of a decompression device (TDT, n = 5; SEMS, n = 1) were also excluded. The primary endpoints of this study were the postoperative morbidity and mortality rates. The secondary endpoints were decompression-related outcomes. Additionally, propensity score matched (PSM) analysis was conducted in short-term outcomes between the groups.

RESULTS

The SEMS group had significantly higher proportion of right-sided tumor and bigger tumor size compared with those of the TDT group. The SEMS group had a significantly higher proportion of patients who underwent laparoscopic surgery, and consequently, a longer surgical duration than did the TDT group. Higher rates of insertion failure and perforation were recognized in the TDT group than in the SEMS group (10.0% versus 3.6% and 8.9% versus 0.0%, respectively), although these differences were not statistically significant (P = 0.406 and 0.291, respectively). The two groups showed similar occurrences of anastomotic leakage, bowel obstruction, overall complications, and mortality. Compared with the TDT group, the SEMS group had a significantly lower rate of surgical site infection (24.4% versus 3.6%, respectively; P = 0.023 and P = 0.025 after PSM) and a shorter length of hospital stay (median, 21 d [interquartile range, 18-29 d] versus 38 d [interquartile range, 28-45 d], respectively; P = 0.015 and P = 0.003 after PSM). Solid food intake after decompression and preoperative temporary discharge occurred only in the SEMS group.

CONCLUSIONS

Preoperative SEMS insertion for MLBO is effective with at least equivalent short-term outcomes and superior preoperative quality of life compared with decompression using TDT.

Role of colonic stents in the management of colorectal cancers

Colorectal cancer is one of the commonly encountered cancers across the Western World. In United Kingdom, this constitutes third most common ranked cancer and second most common ranked cause of cancer related deaths. Its acute presentation as a malignant colonic obstruction imposes challenges in its management. Colonic stent has been used for many years to alleviate acute obstruction in such cases allowing optimisation of patient’s physiological status and adequate staging of cancer. In this review, current literature evidence regarding use of colonic stent in acute malignant colonic obstruction is critically appraised and recommendations on the use of colonic stent are advocated.

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

OBJECTIVES

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

METHODS

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

RESULTS

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

Comparison of long-term outcomes of colonic stent as "bridge to surgery" and emergency surgery for malignant large-bowel obstruction: a meta-analysis

BACKGROUND

The short-term safety and efficacy of insertion of a self-expandable metallic colonic stent followed by elective surgery, bridge to surgery (BTS), for malignant large-bowel obstruction (MLBO) have been well described. However, long-term oncological outcomes are still debated. Hence, this study is conducted to evaluate long-term outcomes of colonic stent insertion followed by surgery for MLBO.

METHODS

A comprehensive electronic literature search through May 2014 was performed to identify studies comparing long-term outcomes between BTS and emergency surgery for MLBO. The main outcome measures were overall survival (OS), disease-free survival (DFS), and recurrence. A meta-analysis was performed using random-effects models to calculate risk ratios (RRs) with 95 % confidence intervals (95 % CIs).

RESULTS

There were 11 studies that matched the criteria for inclusion, yielding a total of 1136 patients, of whom 432 (38.0 %) underwent BTS and 704 (62.0 %) underwent emergency surgery. In OS analyses of all patients and patients who underwent curative resection, BTS was similar to emergency surgery [(RR = 0.95; 95 % CI 0.75-1.21; P = 0.66) (RR = 0.96; 95 % CI 0.67-1.37; P = 0.82), respectively]. DFS (RR = 1.06; 95 % CI 0.91-1.24; P = 0.43) and recurrence (RR = 1.13; 95 % CI 0.82-1.54; P = 0.46) did not differ significantly between the BTS and emergency surgery groups.

CONCLUSIONS

Results of this meta-analysis on long-term as well as well-described short-term outcomes suggest that BTS could be a promising alternative strategy for MLBO patients.

Preoperative colonoscopy through the colonic stent in patients with colorectal cancer obstruction

AIM: To evaluate the feasibility of a preoperative colonoscopy through a self-expendable metallic stent (SEMS) and to identify the factors that affect complete colonoscopy.

METHODS: A total of 48 patients who had SEMS placement because of acute malignant colonic obstruction underwent preoperative colonoscopy. After effective SEMS placement, patients who showed complete resolution of radiological findings and clinical signs of acute colon obstruction underwent a standard bowel preparation. Preoperative colonoscopy was then performed using a standard colonoscope. If the passage of colonoscope was not feasible gastroscope was used. After colonoscopy, cecal intubation time, grade of bowel preparation, tumor location, stent location, presence of synchronous polyps or cancer, damage to colonoscopy and bleeding, and stent migration after colonoscopy were recorded.

RESULTS: Complete evaluation with colonoscope was possible in 30 patients (62.5%). In this group, adenoma was detected in 13 patients (43.3%). The factors that affected complete colonoscopy were also analyzed: Tumor location at an angle; stent placement at an angle; and stent expansion diameter, which affected complete colonoscopy significantly. However in multivariate analysis, stent expansion diameter was the only significant factor that affected complete colonoscopy. Complete evaluation using additional gastroscope was feasible in 42 patients (87.5%).

CONCLUSION: Preoperative colonoscopy through the colonic stent using only conventional colonoscope was unfavorable. The narrow expansion diameter of the stent may predict unfavorable outcome. In such a case, using small caliber scope should be considered and may expect successful outcome.

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.

CT colonography in the diagnosis and management of colorectal cancer: Emphasis on pre- and post-surgical evaluation

This article addresses the use of computed tomographic colonography (CTC) for the diagnosis and management of colorectal cancer, focusing on presurgical evaluation of the colon proximal to an occlusive cancer and surveillance after cancer resection surgery. The key evidences accumulated in the literature and future work needed are summarized. CTC is a technically robust and the most practical method to evaluate the colon proximal to an occlusive cancer, which prevents colonoscopic examination past the occlusion, either before or after metallic stent placement. The high sensitivity of CTC for detecting cancers and advanced adenomas in the proximal colon can help prevent additional surgical procedures in patients showing negative results. However, the accuracy of CTC for distinguishing intramural cancers from adenomas is low, and the technique is limited in guiding management when a medium-sized lesion that do not show invasive features such as pericolic extension or nodal metastasis is found in the proximal colon. A maximal diameter ≥ 15 mm has been proposed as a criterion for surgical removal of proximal lesions. However, this needs to be verified in a larger cohort. In addition, the influence of presurgical CTC results on the current post-cancer resection colonic surveillance timeline remains to be determined. CTC can be readily added to the routine abdominopelvic CT in the form of contrast-enhanced CTC, which can serve as an effective stand-alone tool for post-cancer resection surveillance of both the colorectum and extracolonic organs. Although the accuracy of CTC has been demonstrated, its role in the current colonoscopy-based postoperative colonic surveillance protocols remains to be determined. Readers of CTC also need to be knowledgeable on the colonic lesions that are unique to the postoperative colon.

Own experiences of endoscopic self-expandable stent placement for malignant colorectal ileus

Introduction

Acute low neoplasm ileus requires emergency surgery. Nowadays there are increased numbers of patients with comorbidities, which causes higher risk of intra- and postoperative complications.

Aim

To evaluate the clinical usefulness of endoscopic self-expandable stent placement for malignant colorectal ileus.

Material and methods

Twenty-one patients (8 women and 13 men), mean age 66.7 years, with low neoplasm obstruction, underwent endoscopic stenting of the stricture. This procedure was performed as a bridge to the surgery especially for high-risk patients. Eight of them had coagulation system impairment, 5 severe metabolic disorders, 4 circulatory insufficiency, 3 severe malnutrition and 1 patient undiagnosed synchronic rectal tumor. In 10 patients cancer was located in the sigmoid colon, in 7 in the rectum, in 2 in the ascending colon, and the transverse and ascending colon was involved in another 2 patients.

Results

All 21 patients (100%) underwent endoscopic stenting successfully. There were no complications after stent placement. The authors underline that placement of expandable metallic stents for patients with malignant colon obstruction with acute ileus is a safe and effective method. It gives an opportunity for quick balance of fluid, electrolyte, and the coagulation system and improvement of efficiency of the circulatory and respiratory system.

Conclusions

Endoscopic treatment of ileus helps precisely estimate tumor advancement and gives the possibility of a single stage radical surgical procedure.

Self-expanding metallic stents for palliation and as a bridge to minimally invasive surgery in colorectal obstruction

Self-expanding metallic stents are effective for the palliation of malignant obstruction. This study indicates that stents for bowel obstruction may allow for minimally invasive surgical intervention with a shorter hospital stay, lower stoma rate, and earlier chemotherapy administration.

Background and Objectives:

Acute colorectal obstruction is a potentially life-threatening emergency that requires immediate surgical treatment. Emergency procedures had an associated mortality rate of 10% to 30%. This encouraged development of other options, most notably self-expanding metallic stents. The primary endpoint of this study to is to report our group's experience.

Methods:

We performed a retrospective review of 37 patients who underwent self-expanding metallic stent placement for colorectal obstruction between July 2000 and May 2012. Data collected were age, comorbidities, diagnosis, intent of intervention (palliative vs bridge to surgery), complications, and follow-up.

Results:

The study comprised 21 men (56.76%) and 16 women (43.24%), with a mean age of 67 years. The intent of the procedure was definitive treatment in 22 patients (59.46%) and bridge to surgery in 15 (40.54%). The highest technical success rate was at the rectosigmoid junction (100%). The causes of technical failure were inability of the guidewire to traverse the stricture and bowel perforation related to stenting. The mean follow-up period was 9.67 months. Pain and constipation were the most common postprocedure complications.

Discussion:

The use of a self-expanding metallic stent has been shown to be effective for palliation of malignant obstruction. It is associated with a lower incidence of intensive care unit admission, shorter hospital stay, lower stoma rate, and earlier chemotherapy administration. Laparoscopic or robotic surgery can then be performed in an elective setting on a prepared bowel. Therefore the patient benefits from advantages of the combination of 2 minimally invasive procedures in a nonemergent situation. Further large-scale prospective studies are necessary.

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.

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.

Outcome of 141 cases of self-expandable metallic stent placements for malignant and benign colorectal strictures in a single center

BACKGROUND

The use of a self-expandable metallic stent (SEMS) has emerged as an alternative treatment option for malignant colorectal obstruction. Although the technical success rate of SEMS has been widely reported, outcome data are limited.

METHODS

This retrospective study evaluated the short- and long-term outcomes of colorectal SEMS for malignant and benign disease in patients who underwent SEMS at a single center.

RESULTS

One surgeon inserted all stents under endoscopic and fluoroscopic guidance; 141 SEMS procedures were performed in 133 patients (82 males, mean age 69 years). The SEMS procedure was undertaken for: palliation of malignant obstruction in 30 patients (36 cases), and the technical success rate was 94%; a bridge to surgery for colorectal cancers in 98 patients/cases, and the technical success rate was 91%; benign stricture in 5 patients (7 cases), and the technical success rate was 100%. Due to anatomical differences, the success rate was lower at the cecum, descending colon, and sigmoid than in the rectosigmoid and rectum. In 11 cases of technical failures, the failures were due to technical problems in 9 cases (82%) and due to the state of the stricture in 2 cases (18%). Procedure-related complications occurred in 6 patients (4%): perforation in 3 and migration in 3. All perforation cases and one migration case underwent emergency surgery. There was no mortality. In the bridge to surgery group, postoperative complications were much lower in the clinical success cases (6%) than in the failure group (36%). In the palliation treatment group, long-term SEMS migration occurred in 4 patients (14%), and re-obstruction occurred in 5 patients (18%); the mean insertion period was 201 (range: 10-576) days.

CONCLUSIONS

Colorectal SEMS had feasible short and long-term results and low morbidity, making it a viable option for various types of colorectal obstruction with careful attention to the indications.

Colonic perforation after stent placement for malignant colorectal obstruction--causes and contributing factors

Self-expanding metal stents (SEMS) are used to manage malignant colorectal obstruction. Colonic perforation is the most worrisome complication from colonic stenting. We reviewed causes and contributing factors of perforation with colonic stent placement in patients with malignant colorectal obstruction. Articles from both English and foreign language publications were identified from Medline. Data were collected on causes, timing, treatment and mortality related to perforation. A total of 2287 patients from 82 articles were included in this analysis, which showed an overall perforation rate of 4.9%. Perforation rates for palliation and bridge to surgery (BTS) were not significantly different (4.8% vs. 5.4%, p = 0.66); over 80% occurred within 30 days of stent placement (half during or within one day of the procedure). The mortality rate related to perforation was 0.8% per stented patient, but the mortality of patients experiencing perforation was 16.2%. There was no significant difference (p = 0.78) in the mortality rates between the palliation and the BTS group and concomitant chemotherapy, steroids, and radiotherapy are risk factors of perforation. The overall perforation related mortality is far less than that of patients undergoing emergency surgery for bowel obstruction.

CT colonography after metallic stent placement for acute malignant colonic obstruction

PURPOSE

To evaluate the feasibility of using computed tomographic (CT) colonography for preoperative examination of the proximal colon after metallic stent placement in patients with acute colon obstruction caused by colorectal cancer.

MATERIALS AND METHODS

Institutional review board approval was obtained, and patient informed consent was waived. Fifty patients (mean age +/- standard deviation, 58.5 years +/- 11.7), who demonstrated no postprocedural complication after successful placement of self-expandable metallic stents to treat acute colon obstruction caused by cancer, underwent CT colonography 1-43 days (median, 5 days) after stent placement. CT colonography was performed after cathartic preparation by using magnesium citrate (n = 20) or sodium phosphate (n = 3), combined with oral bisacodyl, or by using polyethylene glycol (n = 27). Fecal/fluid tagging was achieved by using 100 mL of meglumine diatrizoate. The colon was distended by means of pressure-monitored CO(2) insufflation. The sensitivity and specificity of CT colonography in evaluating the colon proximal to the stent and CT colonography-related complications were assessed. The 95% confidence intervals (CIs) were calculated for proportional data.

RESULTS

Per-lesion and per-patient sensitivities of CT colonography for lesions 6 mm or larger in diameter in the colon proximal to the stent were 85.7% (12 of 14 lesions; 95% CI: 58.8%, 97.2%) and 90% (nine of 10 patients; 95% CI: 57.4%, 99.9%), respectively. CT colonography depicted all synchronous cancers (two lesions) and advanced adenomas (five lesions). Per-patient specificity for lesions 6 mm and larger in the proximal colon was 85.7% (18 of 21 patients; 95% CI: 64.5%, 95.9%). CT colonography did not generate any false diagnosis of synchronous cancer. False-positive findings at CT colonography did not result in a change in surgical plan for any patients. No CT colonography-associated stent dislodgment/migration or colonic perforation occurred in any patient (95% CI: 0%, 6.2%).

CONCLUSION

CT colonography is a safe and useful method for preoperative examination of the proximal colon after metallic stent placement in patients with acute colon obstruction caused by cancer. (c) RSNA, 2010.

Long-Term Outcome of Endoscopic Colorectal Stenting for Malignant and Benign Disease

Although the technical success rate of endoscopic stenting has been defined, there is a paucity of outcome data. The purpose of this study was to evaluate the long-term results of colorectal stenting for both malignant and benign disease. A retrospective review was conducted of patients who underwent stenting at a tertiary center over 4 years. One surgeon performed all stents under endoscopic and fluoroscopic guidance. A total of 49 stent procedures were performed in 36 patients (19 females, mean age 65 years). Mean follow-up was 15 months. Twenty-eight patients (78%) underwent stenting for malignant disease and eight patients (22%) for benign conditions. The most common reason for intervention was obstruction (81%). Technical success rate was 72 per cent. Carcinomatosis was associated with a higher technical failure rate. Procedural related complications occurred in two patients (6%). Long-term stent migration rate was 24 per cent and was more common in patients with benign disease and patients who received nonmetal stents or stents with diameter < 25 mm. Endoscopic reintervention was required in 33 per cent of patients with initial technical success. Long-term need for subsequent operative intervention was 14 per cent. Endoscopic stenting is a viable option for a select group of patients with colorectal disease. Patient's selection and stent choice influence outcome.

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.

Comparison of one-stage managements of obstructing left-sided colon and rectal cancer: stent-laparoscopic approach vs. intraoperative colonic lavage

PURPOSE

We evaluated the operative outcomes of laparoscopic surgery following self-expandable metallic stent compared to one-stage emergency surgical treatment.

METHODS

From April 1996 to October 2007, 95 consecutive patients with left-sided malignant colorectal obstruction were enrolled. Twenty-five patients were assigned to the preoperative stenting and elective laparoscopic surgical treatment group (SLAP) and 70 to the emergency open surgery with intraoperative colon lavage group (OLAV).

RESULTS

Among the 25 patients in the SLAP group, a primary anastomosis was possible in all patients and a diverting stoma was needed in one patient. The operative time was shorter in the SLAP group (198.53 vs. 262.17 min, P = 0.002). Tumor size, number of retrieved lymph nodes, and pathological stage were similar in both groups. The rate of anastomotic failure was similar and postoperative complications occurred less in the SLAP group (5.9% vs. 31.4%, P = 0.034). The passage of flatus and oral intake were resumed earlier in the SLAP group (2.88 vs. 3.68 days, P = 0.046 and 5.18 vs. 6.65 days, P < 0.001, respectively). The postoperative hospital stay was shorter in the SLAP group (10 vs. 15.4 days, P = 0.013).

CONCLUSIONS

In patients with left-sided malignant colon and rectal obstruction, laparoscopic surgery after SEMS could be safely performed with successful early postoperative outcomes.

Stents and stentability: treatment for malignant bowel obstruction

Colonic stents offer a palliative treatment for patients with malignant bowel obstruction otherwise requiring surgery and possible stoma, or as a bridge to surgery for potentially curative malignant disease. This article reviews the indications, risks and benefits of stent insertion.

Use of modified multidetector CT colonography for the evaluation of acute and subacute colon obstruction caused by colorectal cancer: a feasibility study

PURPOSE

This study was designed to evaluate the feasibility of using CT colonography with a modified procedural protocol for diagnosis and cancer staging in patients with suspected acute or subacute colon obstruction caused by colorectal cancer.

METHODS

Following colonic cleansing with lukewarm water enemas, thin-collimation CT colonography was performed on 47 patients (15 women and 32 men, mean age, 68 years) in the precontrast prone position and in the supine position after the intravenous administration of a contrast agent. The surgical and pathologic findings served as a reference standard.

RESULTS

In 44 of 47 patients, colon distention was caused by obstruction, and pathologic examination confirmed colorectal cancer in 41 of these 44 patients. CT colonography correctly located all tumors and successfully identified noncancerous causes of colon distention in five patients. The overall accuracy of staging was 97.6 percent for the T category, 73.2 percent for N, and 100 percent for M. Two synchronous colorectal cancers were correctly identified.

CONCLUSIONS

When appropriate protocol modifications regarding colon cleansing and air insufflation are made to take the clinical situation into account, CT colonography is a technically feasible, accurate, and well-tolerated method for tumor evaluation and cancer staging in patients with acute and subacute colon obstruction.

Endoscopic treatment of colonic obstruction

PURPOSE OF REVIEW

Over the past 15 years, great strides have been made in the nonsurgical management of malignant large bowel obstruction. Progress continues, particularly in the area of self-expanding metal stents. The purpose of this review is to assess the available endoscopic techniques for colonic decompression and document the inexorable trend toward supremacy of the self-expanding metal stent in this arena.

RECENT FINDINGS

Stents are being designed with the structure and function of the colon in mind allowing better and longer-lasting palliation. Improvement in the design of the colonic decompression tube allows a low-tech approach to the palliation of colonic obstruction. Argon plasma coagulation is helpful in restoring continuity of the obstructed colonic lumen in certain circumstances.

SUMMARY

As a consequence of technological innovation and growing expertise in the community, gastroenterology is becoming the go to specialty in the early management and palliation of malignant bowel obstruction.

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.

Mechanical obstruction of the small bowel and colon

Mechanical obstruction of the small bowel and colon is moderately common, accounting for several hundred thousand admissions per year in the United States. Patients generally present with abdominal pain, nausea and emesis, abdominal distention, and progressive obstipation. Clinical findings of high fever, localized severe abdominal tenderness, rebound tenderness, severe leukocytosis, or metabolic acidosis suggest possible complications of bowel necrosis, bowel perforation, or generalized peritonitis. Differentiation of total mechanical obstruction from partial mechanical obstruction and pseudo-obstruction is important because total mechanical obstruction is generally treated surgically,whereas the other two entities are usually treated medically. Mechanical obstruction is usually suggested by plain abdominal radiographs, and confirmed by small bowel follow through,abdominal CT, or CT enteroclysis.

Preoperative colonic stenting: how, when and why?

PURPOSE OF REVIEW

Acute colonic obstruction due to malignancy is often a surgical emergency. Surgical decompression with colostomy with or without resection and eventual re-anastomosis has traditionally been the treatment of choice. These procedures have been associated with a significant morbidity and mortality rate. Preoperative colonic stenting is effective for decompressing the obstructed colon and may allow for surgery to be performed on an elective basis.

RECENT FINDINGS

Although randomized clinical data are lacking, the role for preoperative stenting in the emergent management of acute malignant colonic obstruction has been supported by cost-effectiveness analysis studies and several pooled analyses that demonstrate efficacy and safety.

SUMMARY

This review evaluates the latest developments in colonic stent technology, indications for use in the preoperative setting, and evidence to support their use in this setting.

The role of SEMS in malignant and benign colon obstruction

SEMS are highly valuable in the management of pati-ents with malignant colon obstruction with high technical and clinical success. Currently, their role is in colon deco-mpression as a bridge before surgery and in the palliative management of inoperative patients. SEMS appear to be more effective and less costly than emergency surgery. SEMS should be avoided in benign strictures. More data is needed in reference to the role of plastic expandable stents in the management of patients with benign colon strictures.