Outcomes Following Pelvic Exenteration for Locally Recurrent Rectal Cancer With and Without En Bloc Sacrectomy.

BACKGROUND: Extended radical resection is often the only chance of cure for locally recurrent rectal cancer. Recurrence in the posterior compartment often necessitates en bloc sacrectomy as part of pelvic exenteration in order to obtain clear resection margins and provide survival benefit.

OBJECTIVE: To compare oncological, morbidity and quality of life outcomes, following pelvic exenteration with and without en bloc sacrectomy for recurrent rectal cancer.

DESIGN: Comparative Cohort study with retrospective analysis of prospectively collected data.

SETTING: This study was conducted at a high volume pelvic exenteration center.

PATIENTS: Those who underwent pelvic exenteration for locally recurrent rectal cancer between 1994 and 2022.

MAIN OUTCOME MEASURES: Overall survival, post-operative morbidity, R0 resection margin and quality of life outcomes.

RESULTS: A total of 305 (31.6%) of 965 patients underwent pelvic exenteration for locally recurrent rectal cancer. 64.3% of patients were male with a median age of 62 (range, 29-86). 185 patients (60.7%) underwent en bloc sacrectomy, 65 (35.1%) underwent high transection, 119 (64.3%) had sacrectomy below S2. R0 resection was achieved in 80% of patients with sacrectomy and 72.5% without. Sacrectomy patients experienced more postoperative complications without increased mortality. Median overall survival was 52 months, 47 months with sacrectomy and 73 months without (p = 0.059). Quality of life scores were not significantly different across physical component (p = 0.346), mental component (p = 0.787) or Functional assessment of cancer therapy-Colorectal (p = 0.679) scores at 24 month follow up.

LIMITATIONS: Generalizability of these findings may be limited outside of sub-specialist exenteration units. Selection bias exists in a retrospective analysis.

CONCLUSIONS: Patients undergoing pelvic exenteration with and without en bloc sacrectomy for locally recurrent rectal cancer experience similar rates of R0 resection, survival and quality of life outcomes. As R0 remains the most important predictor of survival the requirement of sacral resection should prompt referral to a subspecialist center which performs sacrectomy routinely. See Video Abstract.