Octreotide prescribing patterns in the palliation of symptomatic inoperable malignant bowel obstruction patients at a single US academic hospital

The range and suitability of outcome measures used in the assessment of palliative treatment for inoperable malignant bowel obstruction: A systematic review

BACKGROUND

Malignant bowel obstruction, a complication of certain advanced cancers, causes severe symptoms which profoundly affect quality of life. Clinical management remains complex, and outcome assessment is inconsistent.

AIM

To identify outcomes evaluating palliative treatment for inoperable malignant bowel obstruction, as part of a four-phase study developing a core outcome set.

DESIGN

The review is reported in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA); PROSPERO (ID: CRD42019150648). Eligible studies included at least one subgroup with obstruction below the ligament of Treitz undergoing palliative treatment for inoperable malignant bowel obstruction. Study quality was not assessed because the review does not evaluate efficacy.

DATA SOURCES

Medline, Embase, the Cochrane Database, CINAHL, PSYCinfo Caresearch, Open Grey and BASE were searched for trials and observational studies in October 2021.

RESULTS

A total of 4769 studies were screened, 290 full texts retrieved and 80 (13,898 participants) included in a narrative synthesis; 343 outcomes were extracted verbatim and pooled into 90 unique terms across six domains: physiological, nutrition, life impact, resource use, mortality and survival. Prevalent outcomes included adverse events (78% of studies), survival (54%), symptom control (39%) and mortality (31%). Key individual symptoms assessed were vomiting (41% of studies), nausea (34%) and pain (33%); 19% of studies assessed quality of life.

CONCLUSIONS

Assessment focuses on survival, complications and overall symptom control. There is a need for definitions of treatment 'success' that are meaningful to patients, a more consistent approach to symptom assessment, and greater consideration of how to measure wellbeing in this population.

Medical Management of Inoperable Malignant Bowel Obstruction

OBJECTIVE

To review medical management of inoperable malignant bowel obstruction.

DATA SOURCES

A literature review using PubMed and MEDLINE databases searching malignant bowel obstruction, etiology, types, pathophysiology, medical, antisecretory, anti-inflammatory, antiemetic drugs, analgesics, promotion of emptying, prevention of infection, anticholinergics, somatostatin analogs, gastric antisecretory drugs, prokinetic agents, glucocorticoid, opioid analgesics, antibiotics, enema, and adverse effects.

STUDY SELECTION AND DATA EXTRACTION

Randomized or observational studies, cohorts, case reports, or reviews written in English between 1983 and November 2020 were evaluated.

DATA SYNTHESIS

Malignant bowel obstruction (MBO) commonly occurs in patients with advanced or recurrent malignancies and severely affects the quality of life and survival of patients. Its management remains complex and variable. Medical management is the cornerstone of MBO treatment, with the goal of reducing distressing symptoms and optimizing quality of life. Until now, there has been neither a standard clinical approach nor registered medications to treat patients with inoperable MBO.

RELEVANCE TO PATIENT CARE AND CLINICAL PRACTICE

This review provides information on the etiology, type and pathophysiology, and medical treatment of MBO and related adverse reactions of the drugs commonly used, which can greatly assist clinicians in making clinical decisions when treating MBO.

CONCLUSIONS

Published research shows that medical management of MBO mainly consists of antisecretory, anti-inflammatory strategies, controlling vomiting and pain, promoting emptying, preventing infection, and combination therapy. Being knowledgeable about the most current treatment options, the related adverse effects, and the evidence supporting different practices is critical for clinicians to provide individualized medical therapy for MBO patients.

Obstruction-Free Survival Following Operative Intervention for Malignant Bowel Obstruction in Appendiceal Cancer

BACKGROUND

Patients with peritoneal metastases from appendiceal cancer are at high risk of malignant bowel obstruction (MBO), which is associated with significant morbidity and mortality. There are no definitive treatment guidelines regarding operative intervention for MBO. We sought to evaluate the efficacy and safety of operative intervention in this population.

METHODS

We identified patients with peritoneal metastases from appendiceal cancer who underwent surgery for MBO at our institution between 2011 and 2018. Baseline characteristics, postoperative complications, and follow-up data were collected. The primary endpoint was obstruction-free survival (OFS). Other endpoints were postoperative recovery of bowel function, 60-day Clavien-Dindo (CD) morbidity, and overall survival (OS).

RESULTS

Twenty-six patients underwent operative treatment for MBO, of whom 14 had high-grade (HG) histology and 12 had low-grade (LG) histology. Seven (25.9%) patients had severe (CD grade 3 or higher) 60-day complications, including one (3.8%) postoperative death. All remaining patients had return of bowel function and resumed oral intake during hospitalization. Six (23.1%) patients had repeat admissions for MBO after surgery. Median OFS was 17.0 months (95% confidence interval [CI] 2.3-31.8), and median OS was 18.5 months (95% CI 3.6-33.3) following surgery.

CONCLUSION

In this carefully selected group of patients with peritoneal metastases from appendiceal cancer, surgery for MBO provided durable palliation with acceptable morbidity.

Management of Malignant Bowel Obstruction Associated With GI Cancers

For many patients with GI malignancies, the seeding of the abdominal cavity with tumor cells, called peritoneal carcinomatosis, is a common mode of metastases and disease progression. Prognosis for patients with this aspect of their disease remains poor, with high disease-related morbidity and complications. Uniform and proven practices that provide optimal palliative care and quality of life for these patients are needed. The objective of this review is to critically assess the current literature regarding palliative strategies in the management of peritoneal carcinomatosis and associated symptoms in patients with advanced GI cancers. Despite encouraging results in the select population where cytoreductive surgery and intraperitoneal chemotherapy are indicated, the majority of patients who develop peritoneal carcinomatosis in the setting of GI cancers have poor prognosis, with malignant bowel obstruction representing a common terminal phase of their disease process. For all patients with peritoneal carcinomatosis, aggressive symptom control and early multimodality palliative care as further outlined should be sought.

Somatostatin Analogues Compared With Placebo and Other Pharmacologic Agents in the Management of Symptoms of Inoperable Malignant Bowel Obstruction: A Systematic Review

CONTEXT

Somatostatin analogues are commonly used to relieve symptoms in malignant bowel obstruction (MBO) but are more expensive than other antisecretory agents.

OBJECTIVES

To evaluate the evidence of effectiveness of somatostatin analogues compared with placebo and/or other pharmacologic agents in relieving vomiting in patients with inoperable MBO.

METHODS

MEDLINE, EMBASE, CINAHL, and The Cochrane Controlled Trials Register databases were systematically searched; reference lists of relevant articles were hand searched. Cochrane risk of bias tool was used.

RESULTS

The search identified 420 unique studies. Seven randomized controlled trials (RCTs) met the inclusion criteria (six octreotide studies and one lanreotide); 220 people administered somatostatin analogues and 207 placebo or hyoscine butylbromide. Three RCTs compared a somatostatin analogue with placebo and four with hyoscine butylbromide. Two adequately powered multicenter RCTs with a low Cochrane risk of bias reported no significant difference between somatostatin analogues and placebo in their primary end points. Four RCTs with a high/unclear Cochrane risk of bias reported that somatostatin analogues were more effective than hyoscine butylbromide in reducing vomiting.

CONCLUSION

There is low-level evidence of benefit with somatostatin analogues in the symptomatic treatment of MBO. However, high-level evidence from trials with low risk of bias found no benefit of somatostatin analogues for their primary outcome. There is debate regarding the clinically relevant study end point for symptom control in MBO and when it should be measured. The role of somatostatin analogues in this clinical situation requires further adequately powered, well-designed trials with agreed clinically important end points and measures.

Surgery for the resolution of symptoms in malignant bowel obstruction in advanced gynaecological and gastrointestinal cancer

BACKGROUND

This is an update of the original Cochrane review published in Issue 4, 2000. Intestinal obstruction commonly occurs in progressive advanced gynaecological and gastrointestinal cancers. Management of these patients is difficult due to the patients' deteriorating mobility and function (performance status), the lack of further chemotherapeutic options, and the high mortality and morbidity associated with palliative surgery. There are marked variations in clinical practice concerning surgery in these patients between different countries, gynaecological oncology units and general hospitals, as well as referral patterns from oncologists under whom these patients are often admitted.

OBJECTIVES

To assess the efficacy of surgery for intestinal obstruction due to advanced gynaecological and gastrointestinal cancer.

SEARCH METHODS

We searched the following databases for the original review in 2000 and again for this update in June 2015: CENTRAL (2015, Issue 6); MEDLINE (OVID June week 1 2015); and EMBASE (OVID week 24, 2015).We also searched relevant journals, bibliographic databases, conference proceedings, reference lists, grey literature and the world wide web for the original review in 2000; we also used personal contact. This searching of other resources yielded very few additional studies. The Cochrane Pain, Palliative and Supportive Care Review Group no longer routinely handsearch journals. For these reasons, we did not repeat the searching of other resources for the June 2015 update.

SELECTION CRITERIA

As the review concentrates on the 'best evidence' available for the role of surgery in malignant bowel obstruction in known advanced gynaecological and gastrointestinal cancer we kept the inclusion criteria broad (including both prospective and retrospective studies) so as to include all studies relevant to the question. We sought published trials reporting on the effects of surgery for resolving symptoms in malignant bowel obstruction for adult patients with known advanced gynaecological and gastrointestinal cancer.

DATA COLLECTION AND ANALYSIS

We used data extraction forms to collect data from the studies included in the review. Two review authors extracted the data independently to reduce error. Owing to concerns about the risk of bias we decided not to conduct a meta-analysis of data and we have presented a narrative description of the study results. We planned to resolve disagreements by discussion with the third review author.

MAIN RESULTS

In total we have identified 43 studies examining 4265 participants. The original review included 938 patients from 25 studies. The updated search identified an additional 18 studies with a combined total of 3327 participants between 1997 and June 2015. The results of these studies did not change the conclusions of the original review.No firm conclusions can be drawn from the many retrospective case series so the role of surgery in malignant bowel obstruction remains controversial. Clinical resolution varies from 26.7% to over 68%, though it is often unclear how this is defined. Despite being an inadequate proxy for symptom resolution or quality of life, the ability to feed orally was a popular outcome measure, with success rates ranging from 30% to 100%. Rates of re-obstruction varied, ranging from 0% to 63%, though time to re-obstruction was often not included. Postoperative morbidity and mortality also varied widely, although again the definition of both of these surgical outcomes differed between many of the papers. There were no data available for quality of life. The reporting of adverse effects was variable and this has been described where available. Where discussed, surgical procedures varied considerably and outcomes were not reported by specific intervention. Using the 'Risk of bias' assessment tool, most included studies were at high risk of bias for most domains.

AUTHORS' CONCLUSIONS

The role of surgery in malignant bowel obstruction needs careful evaluation, using validated outcome measures of symptom control and quality of life scores. Further information could include re-obstruction rates together with the morbidity associated with the various surgical procedures.Currently, bowel obstruction is managed empirically and there are marked variations in clinical practice by different units. In order to compare outcomes in malignant bowel obstruction, there needs to be a greater degree of standardisation of management.Since the last version of this review none of the new included studies have provided additional information to change the conclusions.