Prophylactic defunctioning stomas improve clinical outcomes of anastomotic leak following rectal cancer resections: An analysis of the US Rectal Cancer Consortium

Abstract

Purpose: Anastomotic leak (AL) is a complication of low anterior resection (LAR) that results in substantial morbidity. There is immense interest in evaluating immediate postoperative and long-term oncologic outcomes in patients who undergo diverting loop ileostomies (DLI). The purpose of this study is to understand the relationship between fecal diversion, AL, and oncologic outcomes.

Methods: This is a retrospective multicenter cohort study using patient data obtained from the US Rectal Cancer Consortium database compiled from six academic institutions. The study population included patients with rectal adenocarcinoma undergoing LAR. The primary outcome was the incidence of AL among patients who did or did not receive DLI during LAR. Secondary outcomes included risk factors for AL, receipt of adjuvant therapy, 3-year overall survival, and 3-year recurrence.

Results: Of 815 patients, 38 (4.7%) suffered AL after LAR. Patients with AL were more likely to be male, have unintentional preoperative weight loss, and are less likely to undergo DLI. On multivariable analysis, DLI remained protective against AL (p < 0.001). Diverted patients were less likely to undergo future surgical procedures including additional ostomy creation, completion proctectomy, or pelvic washout for AL. Subgroup analysis of 456 patients with locally advanced disease showed that DLI was correlated with increased receipt of adjuvant therapy for patients with and without AL on univariate analysis (SHR:1.59; [95% CI 1.19-2.14]; p = 0.002), but significance was not met in multivariate models.

Conclusion: Lack of DLI and preoperative weight loss was associated with anastomotic leak. Fecal diversion may improve the timely initiation of adjuvant oncologic therapy. The long-term outcomes following routine diverting stomas warrant further study.

Keywords: Anastomotic leak; Clinical outcomes; Fecal diversion; Rectal cancer.

Fig. 1

Flowchart of patient selection. ^*Indicating number of patients excluded, subgroups demonstrate total numbers as conditions are not mutually exclusive. ^✝Total not 777 due to patients (n = 24) lacking diversion status at index operation

Fig. 2

Incidence of AL over time by diversion status. Cumulative incidence of AL over time in the first year post low anterior resection stratified by patients with diverting loop ileostomy (solid line) and without diverting loop ileostomy (dashed line

Fig. 3

Three-year overall survival in patients with and without AL. Kaplan Meier curves illustrating overall survival (OS) over 3 years post-resection. Light gray lines represent patients without AL, and dark gray lines represent patients with AL. A Three-year OS for all patients included in this study stratified by presence or absence of AL. B Three-year OS for the patients with locally advanced (clinical stages II-III) disease stratified by presence or absence of AL

Fig. 4

Percentage of AL diagnosed by time from surgery. Percentage of all patients with AL diagnosed at different time points from surgery. The solid line represents a normal curve overlay

Fig. 5

Competing risk regression for receipt of adjuvant therapy in patients with locally advanced rectal cancer. Receipt of adjuvant therapy, with mortality as a competing risk. A Receipt of adjuvant therapy by presence or absence of AL. The light gray line represents patients with AL, and the dark gray line represents patients without AL. B Receipt of adjuvant therapy by presence or absence of diverting loop ileostomy at index operation. The dashed line represents patients with diverting loop ileostomy at the time of resection, and the solid line represents patients without diverting loop ileostomy at the time of resection