Total neoadjuvant therapy and abdominoperineal resection with sigmoid colon vaginoplasty for locally advanced rectal adenocarcinoma invading the vagina

This report presents a woman in her 70s with locally advanced rectal adenocarcinoma invading the posterior vaginal wall. She received total neoadjuvant therapy (TNT) consisting of six cycles of capecitabine-oxaliplatin followed by long-course chemoradiotherapy, resulting in significant tumour downstaging. Definitive surgery involved extralevator abdominoperineal excision with near-total vaginectomy and reconstruction using a sigmoid colon flap vaginoplasty. Histopathology confirmed an R0 resection, with two of 17 lymph nodes positive for metastasis. The patient recovered uneventfully, with a viable neovagina, preserved lubrication and no stricture formation. Transient urinary retention resolved with conservative management. This case demonstrates that TNT can facilitate curative resection of complex T4b rectal cancers and enable successful functional reconstruction. The use of a sigmoid colon flap provides a versatile and well-vascularised option for vaginal reconstruction, supporting both oncologic safety and quality of life in extensive pelvic resections.