A case of recurrent gastric cancer tolerant to TS-1 therapy successfully treated by TS-1 combined with docetaxel

We report a case of a 58-year-old man with advanced gastric cancer producing sialyl-Tn antigen (STN). Total gastrectomy with distal pancreatectomy and splenectomy was performed. Pathological staging was IV (T 3 N 2 CY1), and most of the cancer cells were strongly positive for anti-STN antibody on immunohistochemical stainings. Serum STN level before the operation was 2,500 U/ml, and the value significantly decreased to the normal range (< 45 U/ml) 2 months after the operation. Low-dose FP (5-FU+CDDP) followed by TS-1 alone (80 mg/day) had been performed as adjuvant chemotherapy. Jaundice appeared and the serum STN level increased again 22 months after the operation. He was diagnosed with a recurrence in the hilar lymph node of the liver. After implantation of expandable stent in the common bile duct, triweekly docetaxel therapy with TS-1 administration (day 1-14) has been performed. Three courses of this therapy have induced a complete response of the recurrent lymph node and the normalization of the serum STN value. No major adverse reaction to this therapy was observed. A complete response and good patient QOL have been achieved during follow-up 8 months after the administration of TS-1 with docetaxel. This case suggests that patients with recurrent gastric cancer who have undergone prior therapy with TS-1 alone could benefit from TS-1 with docetaxel therapy as a second line.