Paclitaxel/carboplatin plus bevacizumab/erlotinib in the first-line treatment of patients with carcinoma of unknown primary site.

INTRODUCTION: This phase II trial evaluated the efficacy and toxicity of the combination of paclitaxel, carboplatin, bevacizumab, and erlotinib in the first-line treatment of patients with carcinoma of unknown primary site (CUP).

METHODS: Patients with previously untreated CUP (adenocarcinoma, poorly differentiated carcinoma, poorly differentiated squamous carcinoma) without clinical or pathologic characteristics of a well-defined treatable subset were eligible. All patients received paclitaxel, carboplatin, bevacizumab, and erlotinib. Treatment cycles were repeated at 21-day intervals. After four cycles, paclitaxel and carboplatin were discontinued; bevacizumab-erlotinib treatment was continued until tumor progression. Patients were initially evaluated for response after completion of two treatment cycles; re-evaluations occurred every 6 weeks thereafter.

RESULTS: Forty-nine of 60 patients (82%) completed four cycles of therapy, and 44 patients (73%) subsequently received maintenance bevacizumab and erlotinib. Thirty-two patients (53%) had major responses to treatment; an additional 18 patients had stable disease. After a median follow-up of 19 months, the median progression-free survival time was 8 months, with 38% of patients progression free at 1 year. The median survival time and 2-year overall survival rate were 12.6 months and 27%, respectively. Treatment was generally well tolerated, with a toxicity profile as predicted based on the known toxicities of each treatment component.

CONCLUSIONS: Empiric treatment with paclitaxel, carboplatin, bevacizumab, and erlotinib is effective and well tolerated as first-line treatment for patients with CUP. Further development of this regimen is warranted.