• carcinoma of unknown primary;
  • chemotherapy;
  • experimental therapeutics;
  • gemcitabine;
  • capecitabine



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).


Patients with CUP received carboplatin AUC 5 mg/mL a minute intravenously Day 1, gemcitabine 1000 mg/m2 intravenously Days 1 and 8, and capecitabine 1600 mg/m2 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.


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 ≥3 adverse events were neutropenia (67%), thrombocytopenia (48%), and anemia (33%).


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. Cancer 2007; 110:770–5. © 2007 American Cancer Society.