Abstract
A female patient in her 50s was admitted to our hospital with melena and weight loss. A close investigation revealed locally advanced rectal cancer, with suspected sacral invasion (lower than S4 level) and lateral lymph node metastasis. Because curative surgery was difficult, we performed local chemoradiotherapy combined with TS-1. Effective tumor reduction was observed on a computed tomography scan after 1 month. After 2 months, rectal amputation with sacral resection was performed. Histopathologically, small amounts of well-differentiated and mucinous carcinoma were present, although most of the tumor comprised fibrous scar tissue, with a negative resection margin. Grade 2 therapeutic efficacy was achieved with preoperative chemoradiotherapy. This treatment is considered effective for unresectable rectal cancer with sacral invasion because it could cause tumor reduction and down-staging, improve the radical resection rate, control local recurrence, and preserve the functions of surrounding structures.
