Self-expandable metallic stents as palliative treatment for malignant colorectal obstruction

Definition of large bowel obstruction by primary colorectal cancer: A systematic review

AIM

Controversies on therapeutic strategy for large bowel obstruction by primary colorectal cancer mainly concern acute conditions, being essentially different from subacute obstruction. Clearly defining acute obstruction is important for design and interpretation of studies as well as for guidelines and daily practice. This systematic review aimed to evaluate definitions of obstruction by colorectal cancer in prospective studies.

METHOD

A systematic search was performed in PubMed, Embase and the Cochrane Library. Eligibility criteria included randomized or prospective observational design, publication between 2000 and 2019, and the inclusion of patients with an obstruction caused by colorectal cancer. Provided definitions of obstruction were extracted with assessment of common elements.

RESULTS

A total of 16 randomized controlled trials (RCTs) and 99 prospective observational studies were included. Obstruction was specified as acute in 28 studies, complete/emergency in five, (sub)acute or similar terms in four and unspecified in 78. Five of 16 RCTs (31%) and 37 of 99 cohort studies (37%) provided a definition. The definitions included any combination of clinical symptoms, physical signs, endoscopic features and radiological imaging findings in 25 studies. The definition was only based on clinical symptoms in 11 and radiological imaging in six studies. Definitions included a radiological component in 100% of evaluable RCTs (5/5) vs. 54% of prospective observational studies (20/37, P = 0.07).

CONCLUSION

In this systematic review, the majority of prospective studies did not define obstruction by colorectal cancer and its urgency, whereas provided definitions varied hugely. Radiological confirmation seems to be an essential component in defining acute obstruction.

Palliative stent for malignant colonic obstruction by extracolonic malignancy: a comparison with colorectal cancer

BACKGROUND AND AIM

Palliative self-expandable metal stent placement for colonic obstruction arising from an extracolonic malignancy might be as useful as that for colorectal cancer, but data are limited. The purposes of this study were to investigate success and complications of stent placement in patients with extracolonic malignancy and to compare long-term clinical outcomes for an extracolonic malignancy group with those for a colorectal cancer group.

PATIENTS AND METHODS

We reviewed short-term and long-term outcomes for patients treated with palliative stents for colonic obstruction by extracolonic malignancy (n = 44) or unresectable colorectal cancer (n = 53) from January 2006 to March 2011.

RESULTS

Neither the technical success (93.2 vs. 98.1 %, respectively; P = 0.326) nor clinical success (77.3 vs. 84.9 %, respectively; P = 0.433) of stent placement differed significantly in the two groups. Complications as a result of stent placement also differed only slightly in the two groups (perforation: 4.8 % (two cases) vs. 0 %, respectively; migration: 4.8 vs. 5.8 %, respectively, P = 0.343). With regard to long-term outcomes, although stent patency was shorter in the extracolonic malignancy group (P = 0.015), because overall survival in this group was also shorter (P = 0.018), it was sufficient for palliative purposes.

CONCLUSIONS

Palliative stent placement was equally effective and safe for treatment of colonic obstruction arising from either extracolonic malignancy or unresectable colorectal cancer. Even in cases of colonic obstruction arising from extracolonic malignancy, stent placement should be considered as primary palliative therapy.

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.

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.

Factors associated with the long-term outcome of a self-expandable colon stent used for palliation of malignant colorectal obstruction

BACKGROUND

The placement of self-expanding metal stents (SEMS) is a safe and effective definitive procedure for the palliation of malignant colorectal obstruction. In this study, the clinical outcomes, including the technical and clinical success rates, and the risk factors associated with the long-term outcomes of palliative SEMS were evaluated.

METHODS

From February 2002 to April 2008, 39 patients (18 men and 21 women) with malignant colorectal obstruction underwent placement of uncovered or covered stents under fluoroscopic or endoscopic guidance. The mean age of the patients was 64.5 +/- 14.6 years (range, 37-96 years).

RESULTS

The technical success rate was 100% (39/39), and the clinical success rate was 87.2% (34/39). Five cases had failed relief of the obstruction due to the development of migration in two patients, two malfunctions, and one perforation. Four patients experienced late complications: migration managed with a palliative colostomy in two patients, tumor ingrowth managed successfully with a second stent in one patient, perforation with an intraabdominal abscess at the upper margin of the stent 4 months after stenting in one patient. The location of the obstruction and the length of the stent were significant factors associated with a good outcome. Shorter stents (<10 cm) had better outcomes than longer stents (>or=10 cm; p = 0.008), and patients with a distal colorectal obstruction had better outcomes than those with a proximal colorectal obstruction (p = 0.015).

CONCLUSION

Patients with bowel obstruction involving a short segment and those with a distal obstruction had better stent outcomes.

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.

Utilisation of specialist care in patients with incurable rectal cancer. a population-based study from Western Norway

INTRODUCTION

About 25% of patients with rectal cancer have incurable disease at the time of diagnosis. In the current study from Western Norway (population of 981 000) we focused on the utilisation of specialist care in patients with primarily incurable rectal cancer.

PATIENTS AND METHODS

Between 1997 and 2002, 1 167 patients were diagnosed with rectal cancer, of whom 297 (25%) had incurable disease, according to consecutive and prospective reporting to the Norwegian Colorectal Cancer Registry. Consumption of specialist care facilities was studied with regard to outpatient contacts, hospital admissions, and various treatment modalities. Data were analysed with regard to age, sex, marital status, type of residence, and geographical access to hospital facilities. Data were available for 287 patients (97%).

RESULTS

The median age was 77 years. Elderly patients (>77 years) more often lived in nursing homes without a spouse. About 60% of the patients were treated with major surgery, chemotherapy or radiotherapy, either alone or in combination. Of those who did not receive such treatment, 87% were elderly. Oncological treatment, either alone or combined with surgery, predicted increased hospital admissions and outpatient contacts. Age >77 years predicted fewer hospital admissions. Survival varied statistically significantly with the various treatment modalities, and was highest for major resections combined with oncological treatment. The majority of the patients living at home died in hospitals (54%) and only 26% died in their homes, while two-thirds of residents of nursing homes died there.

DISCUSSION

Patients with primary incurable rectal cancer are heterogeneous with regard to their needs of treatment. While younger patients receive extensive tumour-related treatment, elderly patients are most commonly treated according to their symptoms. Prospective studies of the effect of various treatment options on the ease of symptoms and improved quality of life in unselected populations are needed.