Stage-by-stage comparison of clinical and oncologic outcomes in ulcerative colitis-associated versus sporadic colorectal cancer: A propensity-matched analysis.

Abstract

Introduction: Patients with ulcerative colitis (UC) have an increased risk of developing colorectal cancer (CRC), which differs in carcinogenesis from sporadic CRC (S-CRC). This study aimed to compare the clinical features and oncologic outcomes between UCCRC and S-CRC groups.

Patients and methods: A retrospective cohort of patients who underwent surgery at Asan Medical Center, Seoul, Korea, between January 2010 to December 2020 comprised 46 patients with UCCRC and 9717 patients with S-CRC. Before propensity score matching (PSM), several variables significantly differed between the 2 groups. PSM was performed at a 1:2 ratio.

Results: Of the 126 analyzed patients after PSM, 42 and 84 patients were in the UCCRC and S-CRC groups, respectively. Five-year overall survival (OS) (82.2% ± 6.1% vs. 81.7% ± 5.2%), 5-year disease-free survival (DFS) (70.9% ± 10.1% vs. 76.1 ± 5.7%), and stage-by-stage survival outcomes were not significantly different between the UCCRC and S-CRC groups. Among stage III patients, the 5-year OS and DFS rates in the UCCRC group were lower than those in the S-CRC group without reaching significance (OS: 33.3% ± 19.2% vs. 68.4% ± 13.1%, P=.078; DFS: 33.3% ± 19.2% vs. 69.2% ± 12.8%, P=.053). Regarding adjuvant chemotherapy, the UCCRC group had more chemotherapy-induced complications than the S-CRC group (21.2% vs. 0%, P=.026).

Conclusion: This study demonstrates that 5-year OS and DFS are equivalent in UCCRC and S-CRC groups, even in stage-by-stage analyses. As the chemotherapy-induced complications differed, this may have affected the oncologic outcomes in stage III CRC.