Survival after urological resections in colorectal cancer - a Swedish nationwide study

Colorectal cancer with overgrowth into urinary organs requires en-bloc resection of involved organs to achieve negative resection margins (R0). This study investigates survival and oncological outcomes after colorectal cancer surgery with resections of urinary organs.

Patients undergoing colorectal cancer surgery with urological resection in Sweden 2007-2018 were identified via the Swedish Colorectal Cancer Registry using the variable "resection of another organ".

A total of 57 907 patients underwent colorectal cancer resection, and 1093 patients had concomitant urological resections: 589 total cystectomies, 345 partial cystectomies, and 159 ureteral resections. The majority undergoing total or partial cystectomy were men (442 (75 %) and 271 (63 %), respectively). R0 was obtained in 509/589 patients (86 %), 296/345 patients (86 %), and 134/169 patients (84 %) for total cystectomy, partial cystectomy, and ureteral resection, respectively. Five-year overall survival rates were 361 patients (61 %) after total cystectomy, 201 patients (58 %) after partial cystectomy, and 85 patients (53 %) after ureteral resection (Kaplan-Meier, Log-rank test p = 0.205). Multivariable analyses adjusted for sex, age, ASA classification, tumour localisation (colon/rectum), cTNM, pTN, year of surgery, and type of surgery (emergency/elective) revealed higher local recurrence rate in the ureteral resection group (hazard ratio: 2.290, 95 % CI: 1.166-4.498), while 5-year overall survival and distant metastases rates did not differ.

Partial cystectomy may represent an option to total cystectomy in selected patients with colorectal cancer overgrowth on urinary organs while maintaining favourable survival and oncological outcomes. Still, selection bias is an inherent problem in the interpretation of results.