Colorectal/GI
non-CME
Ramy Behman, MD PhD
Fellow
University of Toronto
Toronto, Ontario, Canada
Disclosure information not submitted.
Ramy Behman, MD PhD
Fellow
University of Toronto
Toronto, Ontario, Canada
Disclosure information not submitted.
Gursharan Sohi, MD(c)
Medical Student
Sunnybrook Research Institute
Toronto, Ontario, Canada
Disclosure information not submitted.
shady Ashamalla, MD MSc
Assistant Professor
University of Toronto, United States
Disclosure information not submitted.
Sheron Perera, MD PhD
Assistant Professor
University of Toronto, United States
Disclosure information not submitted.
Alyson Mahar, PhD
Assistant Professor
Queens University, United States
Disclosure information not submitted.
Julie Hallet, MD MSc FRCSC FSSO (she/her/hers)
Associate Professor of Surgery
University of Toronto; Odette Cancer Centre - Sunnybrook Health Sciences Centre
Toronto, Ontario, Canada
Disclosure(s): AAA: Speaker (Terminated); AstraZeneca; Bristol Myers Squibb; BTG International Ltd.; MedImmune; and Merck & Co., Inc.: Speaker (Terminated); Ipsen: Speaker (Ongoing); Medtronic: Speaker (Ongoing); Olympus Corporation: Speaker (Ongoing)
Anastomotic leak (AL) is common following colorectal cancer (CRC) resection. Previous studies have suggested an association between AL and disease recurrence, but results have been mixed. We examined the impact of AL after CRC resection on disease-free and overall-survival (DFS; OS) and compared AL to established high-risk criteria for which adjuvant chemotherapy is indicated in CRC.
Methods:
This is a population-based retrospective cohort study of adults with stage I-III CRC undergoing primary resection (2007-2020). Time-to-event analyses compared DFS (accounting for the competing risk of death) and OS between patients with AL and those without. Fine-Gray and Cox models examined the adjusted association between AL and DFS and OS, respectively, with subgroup analyses by disease site (colon/rectum) and stage. Patients were further stratified by presence of established high risk clinical criteria (obstruction and/or perforation) and/or AL to evaluate the association of AL with outcomes, relative to other high-risk criteria.
Results:
Of 57,407 patients included (39,907 colon and 17,500 rectum cancers), AL occurred in 5.9%. Median follow-up was 5.2 (IQR: 2.6-8.8) years. After adjustment, AL was associated with significantly lower DFS for colon (sub-hazard ratio, sHR 1.2, 95%CI 1.1-1.3) but not rectal cancer (sHR 1.0, 95%CI 0.9-1.1). The difference in DFS with was greatest among for Stage II colon cancer, with 3-year DFS of 63.5% (95%CI 61.8%-65.1%) with AL vs 71.4% (95%CI 71.0%-71.8%) without AL (p=0.03). AL was associated with lower OS in both colon (HR 1.4, 95%CI 1.3-1.5 and rectal cancer (HR 1.2, 95%CI 1.1-1.3). Tests of the interaction between AL and chemotherapy were not significant for neither DFS nor OS, suggesting that the impact of AL on outcomes was not mediated by its association with receipt of chemotherapy.
Conclusions:
AL is independently associated with increased risk of cancer recurrence for patients with colon cancer, but not for those with rectal cancer, and with lower OS for both colon and rectal cancers. The association between AL and DFS is comparable to that of other established high-risk criteria for which adjuvant chemotherapy is indicated. The role of adjuvant chemotherapy for patients with AL after CRC resection warrants further investigation in efforts to improve outcomes.