We report two cases of pancreatic cancer with multiple liver metastases for which successful gemcitabine (GEM) +S-1 therapy facilitated radical resection. Case 1: A 40-year-old man with jaundice was diagnosed with pancreatic head cancer and multiple metastases. Radical treatment was not possible. Therefore, he was administered GEM +S-1 (GEM 1,000 mg/m² on days 1 and 8; S-1, 100mg/day for 14 days). Administration of seven courses of therapy achieved complete remission (CR) of the metastatic lesions. Considering the possibility of residual tumors, a subtotal stomach-preserving pancreaticoduodenectomy was performed. Although pathological examination revealed a residual tumor in the primary lesion, R0 resection was achieved. GEM+S-1 therapy was resumed, and the patient is currently relapse-free. Case 2: A 65-year-old man with obstructive jaundice was diagnosed with pancreatic head cancer and multiple metastases. Radical treatment was not possible. Therefore, GEM +S-1 therapy was initiated. After 11 therapy courses, only one metastatic lesion remained. Radical treatment was then deemed possible, and a pylorus-preserving pancreaticoduodenectomy was performed. Pathological examination revealed residual tumors in the primary lesion and the peripancreatic lymph nodes. However, the liver nodules were only fibrotic, and their surgical radicality was R0. GEM +S-1 therapy was resumed, and the patient is currently relapse-free.
Conclusion: The high response rate of GEM+S-1 therapy suggests its usefulness in facilitating radical resection after treatment with (GEM) +S-1.