Feasibility of transanal minimally invasive surgery when performing sacrectomy for advanced primary and recurrent pelvic malignancies

Background: This study aimed to clarify the efficacy and safety of minimally invasive transabdominal surgery (MIS) with transanal minimally invasive surgery (TAMIS) for sacrectomy in advanced primary and recurrent pelvic malignancies. Methods: Using a prospectively collected database, we retrospectively analyzed the clinical, surgical, and pathological outcomes of MIS with TAMIS for sacrectomies. Surgery was performed between February 2019 and May 2023. The median follow-up period was 27 months (5-46 months). Results: Fifteen consecutive patients were included in this analysis. The diagnoses were as follows: recurrent rectal cancer, n=11 (73%); primary rectal cancer, n=3 (20%); and recurrent ovarian cancer, n=1 (7%). Seven patients (47%) underwent pelvic exenteration with sacrectomy, six patients (40%) underwent abdominoperineal resection (APR) with sacrectomy, and two patients (13%) underwent tumor resection with sacrectomy. The median intraoperative blood loss was 235 ml (range, 45–1320 ml). The postoperative complications (Clavien–Dindo grade ≥3a) were graded as follows: 3a, n=6 (40%); 3b, n=1 (7%); and ≥4, n=0 (0%). Pathological examinations demonstrated that R0 was achieved in 13 patients (87%). During the follow-up period, 2 patients (13%) developed local re-recurrence due to recurrent cancer. The remaining 13 patients (87%) had no local disease. Fourteen patients (93%) survived. Conclusions: MIS with TAMIS could lead to a very small amount of blood loss, a low incidence of severe postoperative complications, and an acceptable R0 resection rate, indicating that this novel surgical approach is feasible for selected patients who undergo sacrectomy. Further studies are needed to clarify the long-term oncological feasibility.