A Novel Classification of Posterior Pelvic Exenteration to Assess Prognosis in Female Patients with Locally Advanced Primary Rectal Cancer: A Retrospective Cohort Study from China PelvEx Collaborative

Abstract

Purpose Surgical techniques and the prognosis of posterior pelvic exenteration for locally advanced primary rectal cancer in female patients pose challenges that warrant additional assessment. Therefore, we compared short-term and survival outcomes of posterior pelvic exenteration in female patients using a novel Peking classification. Methods We retrospectively analysed a prospective database from China PelvEx Collaborative in three tertiary referral centres. A total of 172 patients who underwent combined resection for locally advanced primary rectal cancer were classified into four subtypes (PPE-I [64/172], PPE-II [68/172], PPE-III [21/172], and PPE-IV [19/172]) according to the Peking classification; perioperative characteristics and short-term and oncological outcomes were analysed. Results Differences were significant among the four groups regarding colorectal reconstruction (p < 0.001), vaginal reconstruction (p < 0.001), in-hospital complications (p < 0.05), and urinary retention (p < 0.05). The R₀ resection rates for PPE-I, PPE-II, PPE-III, and PPE-IV were 90.6%, 89.7%, 90.5%, and 89.5%, respectively. The 5-year overall survival rates of the PPE-I, PPE-II, PPE-III, and PPE-IV groups were 73.4%, 68.8%, 54.7%, and 37.3%, respectively. Correspondingly, their 5-year disease-free survival rates were 76.0%, 62.5%, 57.7%, and 43.1%, respectively. Notably, PPE-IV demonstrated the lowest 5-year overall survival rate (p < 0.001) and 5-year disease-free survival rate (p < 0.001). Conclusion The Peking classification can aid in determining suitable surgical techniques and conducting prognostic assessments in female patients with locally advanced primary rectal cancer.