Pathological Complete Response of Advanced Rectal Cancer Treated by Preoperative Chemoradiotherapy with Oral Tegafur-Uracil and Leucovorin: A Case Report

A rare case of pathological complete response of advanced rectal cancer treated by preoperative chemoradiotherapy (CRT) with oral tegafur-uracil and leucovorin is reported. A 73-year-old man with bloody stool was diagnosed with type 2 rectal cancer located 6 cm from the anal verge. Examination of biopsy specimens revealed moderately differentiated adenocarcinoma. Computed tomography scans showed no distant or lymph node metastases. With a diagnosis of advanced lower rectal cancer of T3N0M0 stage III according to the TNM classification, he underwent preoperative CRT with oral tegafur-uracil and leucovorin. He did not experience any adverse events due to CRT. An abdominal CT scan and colonoscopy after CRT demonstrated significant tumor reduction. Then, 63 days after CRT, he underwent laparoscopic-assisted low anterior resection and diverting ileostomy. Pathological examination revealed no residual cancer cells. During 15 months of follow-up after his ileostomy was taken down, the patient continued to do well without any signs of recurrence or metastasis. Preoperative CRT with tegafur-uracil and leucovorin may thus represent a safe, well-tolerated, and effective therapeutic strategy for patients with advanced rectal cancer.