Prognosis of ulcerative colitis colorectal cancer vs. sporadic colorectal cancer: propensity score matching analysis

BACKGROUND Ulcerative colitis (UC) harbours a high risk of UC-associated colorectal cancer (UCCC), which is important cause of morbidity and mortality in patients with inflammatory bowel disease. Overall Survival (OS) of patients with UCCC has not been addressed well in the literature. Thus, we compared oncologic outcome of UCCC and sporadic colorectal cancer (SCC) using propensity score matching analysis. METHODS Propensity score matching was performed for 36 patients, a 1:1 matching method stratified into 18 in UCCC and 18 patients in SCC. Matched variables were sex, age, body mass index, tumour stage, histology, preoperative carcinoembryonic antigen (CEA) level, and adjuvant treatment status. Patients with SCC or UCCC were retrospectively retrieved from our database from March 2000 to December 2015. All patients had undergone either oncological segmental resection or total proctocolectomy. RESULTS The majority of cancers were found in the sigmoid colon. Total proctocolectomy was performed only in the UCCC group; however, half of the UCCC group underwent a standard operation. Five cases of postoperative complication occurred within six months in the UCCC group compared to one case in the SCC group. There was no significant difference in recurrence rate (p = 0.361) or OS (p = 0.896) between the arms. CONCLUSION UCCC showed more postoperative complications than SCC, and equivalent oncology outcome, however the difference was not statistically significant. This study represents an experience of a single institution, thus further randomized studies are required to confirm our.