The evolving role of paclitaxel for patients with carcinoma of unknown primary site.

Patients with carcinoma of unknown primary site represent a very heterogeneous clinicopathologic group. Progress has been made in defining important clinical subsets, and specialized pathologic analysis is essential for the poorly differentiated neoplasms. Paclitaxel (Taxol; Bristol-Myers Squibb Company, Princeton, NJ) is a broad-spectrum antineoplastic agent with demonstrated activity in a wide variety of carcinomas. We have combined paclitaxel with carboplatin and oral etoposide for the therapy of patients with unknown primary carcinoma. The overall response rate (47%, with 13% complete responders) compares favorably with any other chemotherapy. Furthermore, the median survival of 13.4 months was notable and encouraging. Toxicity was well-tolerated and no treatment-related deaths occurred. Additional data are needed to more firmly establish the role of paclitaxel for unknown primary cancer.