Phase II trial of carboplatin, gemcitabine, and capecitabine in patients with carcinoma of unknown primary site.

BACKGROUND: The purposes of this study were to evaluate efficacy and toxicity of the combination of carboplatin, gemcitabine, and capecitabine in patients with carcinoma of unknown primary site (CUP).

METHODS: Patients with CUP received carboplatin AUC 5 mg/mL a minute intravenously Day 1, gemcitabine 1000 mg/m(2) intravenously Days 1 and 8, and capecitabine 1600 mg/m(2) orally in divided doses, Days 1-14 of a 21-day cycle for up to 8 cycles. The primary endpoint of the study was objective response rate by intent-to-treat analysis.

RESULTS: Thirty-three patients were treated (median age, 58 years; men:women ratio, 19:14). Most patients had a baseline performance status of 1. The objective response rate was 39.4% (95% CI, 22.9%-57.9%) in all patients, 36.4% in 22 patients with well to moderately differentiated adenocarcinoma, and 40.0% in 20 patients with liver metastases. Median progression-free survival time was 6.2 months (95% CI, 5.4%-8.0%), and median survival time was 7.6 months (95% CI, 6.3-14.1). One and 2-year survival rates were 35.6% and 14.2%, respectively. The most frequent grade > or =3 adverse events were neutropenia (67%), thrombocytopenia (48%), and anemia (33%).

CONCLUSIONS: The combination of carboplatin, gemcitabine, and capecitabine is active in CUP, especially in patients with liver metastases. This regimen may be a potential therapy for CUP patients with good performance status, particularly those with a suspected origin below the diaphragm.