5-fluorouracil and leucovorin as second-line chemotherapy in carcinomas of unknown primary site.

Carcinomas of unknown primary (CUP) are highly malignant diseases which have poor prognosis. We report in the present study the impact on survival and toxicity of a salvage chemotherapy with 5-Fluorouracil (5-FU) and leucovorin (LV) in 25 patients with CUP who failed first-line treatment with cisplatin-based regimens. Chemotherapy was a bimonthly regimen of intravenous LV 200 mg/m2 as a 2-hour infusion followed by a 1-hour bolus 5-FU 400 mg/m2 and a 22-hour continuous infusion 5-FU 600 mg/m2 for 2 consecutive days every 2 weeks. The median number of cycles per patient was 4. Overall toxicity was mild. No objective response was observed. From the start of second-line chemotherapy, the median overall survival was 3 months. The median overall survival from diagnosis was 9 months. Second-line chemotherapy with 5-FU/LV has no impact on survival in patients with CUP.