Background: Carcinomas of unknown primary site (CUPs) are heterogeneous tumors associated with a poor prognosis. This phase II trial was designed to evaluate the efficacy and safety of a novel combination chemotherapy of S-1 and cisplatin (CDDP) in patients with CUP.
Patients and methods: Patients with previously untreated CUPs were eligible for this trial. The treatment schedule consisted of oral S-1 (40 mg/m(2)) twice a day on days 1-21, and intravenous CDDP (60 mg/m(2)) on day 8. This schedule was repeated every 5 weeks.
Results: A total of 46 patients were enrolled. The overall response rate and the disease control rate were 41.3% and 80.4%, respectively. The median overall survival time was 17.4 months. Grade 3/4 neutropenia, thrombocytopenia, and febrile neutropenia occurred in 28.3%, 13.0%, and 2.2% of the patients, respectively.
Conclusion: CDDP plus S-1 combination chemotherapy is well tolerated and active first-line empiric therapies for patients with CUP.