Salvage pancreaticoduodenectomy for localized recurrence after resection of ascending colon cancer: a case report.

A 66-year-old man underwent right hemicolectomy for ascending colon cancer with direct invasion of gallbladder. Numerous aberrant proliferative vessels from the duodenum were noted. The pathological diagnosis was T4bN0M0, Stage IIC, with a KRAS G12D mutation. He received four cycles of adjuvant chemotherapy.

Four months later, a mass approximately 3 cm in diameter involving the duodenum and ileum was identified and diagnosed as localized recurrence with no evidence of distant metastasis. After administration of two cycles of chemotherapy, contrast-enhanced computed tomography demonstrated tumor shrinkage. A pancreaticoduodenectomy was performed, including resection of the involved ileum, and the short segment of transverse colon. Pathological examination revealed adenocarcinoma proliferation extending across the adhesion plane between the duodenum and ileum, infiltrating the muscularis propria of both intestinal walls without intraluminal exposure.

These findings suggested that the tumor originated from residual cancer cells at the dissection plane of the initial surgery. No postoperative adjuvant chemotherapy was administered, in accordance with the patient's wishes. The patient has remained disease-free for more than 7 years after the pancreaticoduodenectomy.