[Emphasize preoperative imaging interpretation and surgical planning for total pelvic exenteration].

Total pelvic exenteration (TPE) is a critical surgical procedure for treating locally advanced rectal cancer (LARC) at stage T4b and locally recurrent rectal cancer (LRRC), where the resectability of pelvic tumors depends on precise preoperative imaging evaluation. Laparotomy primarily aims to exclude abdominopelvic peritoneal metastases. Preoperative assessment involves contrast-enhanced chest/abdominal CT, contrast-enhanced liver MRI (as a supplement when CT findings are unclear), contrast-enhanced pelvic MRI (the preferred modality for evaluating soft tissue planes, organ involvement, and resection scope), and PET-CT (useful for systemic metastasis detection and differentiating scar/fibrosis from tumor). Key focuses include identifying invasion of pelvic wall structures (vascular, neural, muscular planes in lateral, posterior, and floor regions) and the "high-risk zone for major hemorrhage" at the confluence of internal iliac veins. Multidisciplinary team discussions involving radiology, surgery, oncology, and other specialties are essential. These discussions emphasize "en bloc resection" principles, using imaging to define resection planes layer-by-layer to assess R0 resection feasibility, reconstructive strategies, and neoadjuvant therapy. The "Changzheng Surgical Classification" proposed by our center categorizes PE into intra-pelvic exenteration (resecting ≥50% of tissues from ≥2 systems within the bony pelvis) and combined pelvic wall exenteration (involving ≥50% tissues from ≥1 pelvic system plus ≥1 of the 5 pelvic wall regions or ≥2 pelvic wall regions). Preoperative planning based on detailed pelvic anatomical zoning ensures standardized resection and reconstruction, promoting procedural consistency and improving R0 resection rates.