[A Case of Curative Resection for Borderline-Resectable Locally Advanced Rectal Cancer Treated with Preoperative Chemoradiotherapy followed by Extended Surgery].

A 55-year-old man was referred for surgery after colonoscopy revealed type 3 advanced lower rectal cancer in the lower rectum. CT and MRI scan showed no distant metastasis but on the left side of the rectum, there was a 34×30 mm large mass suspicious of lymph node metastasis, which had left-sided wall pelvic fascia invasion. We performed preoperative chemoradiotherapy(CRT)to ensure a secure surgical margin. As a result, the tumor volume was reduced and robot-assisted rectal amputation and bilateral lateral lymph node dissection were performed using a combined transperineal speculum approach. The pathological results showed that circumferential resection margin of 3 mm was secured. The lymph nodes on the left side of the rectum were mostly fibrotic and the tumor component had almost disappeared. Preoperative CRT is useful for securing the surgical margin. The multidisciplinary treatment including extended surgery enabled the curative resection of even highly advanced rectal cancer.