Unresectable duodenal adenocarcinoma excluding the ampullary region is rare, and no standard chemotherapy has been defined for this disease. Although S-1-based chemotherapy is widely administered for advanced gastric cancer, few reports have described advanced duodenal cancer treated with S-1-based chemotherapy. We present herein a case of duodenal adenocarcinoma with liver metastases. The patient was a 72-year-old man with chief complaints of epigastralgia and fever. Gastroduodenal endoscopy revealed an ulcerative lesion on the upper wall of the duodenal bulb, and biopsy specimens showed well-differentiated adenocarcinoma. Computed tomography and ultrasonography showed multiple liver metastases. S-1 (80 mg/m(2) day(-1) on days 1-21) + irinotecan (80 mg/m(2) day(-1) on days 1 and 15) were administered in 4-week intervals as first-line chemotherapy. Tumor markers subsequently normalized, and liver metastases were diminished. The progression-free term was 6 months. Grade 3 neutropenia and diarrhea were observed as adverse events. S-1 + cisplatin and S-1 + docetaxel were administered as second- and third-line chemotherapies, respectively. The patient died due to hepatic failure, with an overall survival of 15 months. S-1-based regimens appear effective and well tolerated, and S-1 may thus represent a useful option for advanced duodenal cancer.
Keywords: Chemotherapy; Duodenal cancer; Irinotecan; Liver metastases; S-1.