A multidisciplinary approach to rectal cancer treatment in ulcerative colitis results in high rate of restorative minimally invasive surgery.

Background and aims Few recent studies focus on the treatment of rectal cancer in patients with ulcerative colitis. We report treatment options and results for this subset of patients with a multimodal approach at two European referral centers. Methods Ulcerative colitis patients diagnosed with rectal cancer arising at less than 15 cm from the anal verge between January 2010 and December 2020 were analyzed. Demographics, clinical data, details of medical and surgical treatment were retrieved from prospectively collected institutional databases. Results Of 132 patients with ulcerative colitis and concomitant colorectal cancer, rectal cancer was diagnosed in 46. The median time between disease onset and rectal cancer diagnosis was 17.5 years. Twenty-one/46 were preoperatively staged as early tumors (cT1-T2/N0). Eleven patients received neoadjuvant chemoradiotherapy for locally advanced extraperitoneal adenocarcinoma, while the rest underwent surgery first. Over two-thirds of the procedures were restorative (68%); a minimally invasive approach was used in 96% of patients with no conversion to open. The median follow-up was 44 months. Local recurrence occurred in 3 patients (6%). The cumulative 3-years cancer-specific survival rate was 94% (and the 3-years disease-free rate was 86%). Conclusion Rectal cancer in ulcerative colitis is a very complex condition. Our results show that surgery for rectal cancer can be delivered with excellent oncologic and functional outcomes in patients with ulcerative colitis. A multidisciplinary discussion among surgeons, gastroenterologists, medical oncologists is key to ensure the appropriate treatment pathway for individual patients.