Treatment of malignant pheochromocytoma/paraganglioma with cyclophosphamide, vincristine, and dacarbazine

BACKGROUND: A long-term follow-up was conducted of 18 patients with a diagnosis of pheochromocytoma/paraganglioma treated with a combination of cyclophosphamide, vincristine, and dacarbazine (CVD). METHODS: The study design was a nonrandomized, single-arm trial conducted at a government medical referral center. Eighteen patients with metastatic malignant pheochromocytoma/paraganglioma were studied. After controlling symptoms of catecholamine excess, patients were treated with cyclophosphamide at 750 mg/m(2), vincristine at 1.4 mg/m(2), and dacarbazine at 600 mg/m(2) on Day 1 and dacarbazine at 600 mg/m(2) on Day 2, every 21 to 28 days. RESULTS: Combination chemotherapy with CVD produced a complete response rate of 11% and a partial response rate of 44%. Median survival from a landmark was 3.8 years for patients whose tumors responded to therapy and 1.8 years for patients whose tumors did not respond (P = .65). All patients with tumors scored as responding reported improvement in their symptoms related to excessive catecholamine release and had objective improvements in blood pressure. CVD was well tolerated with only grade I/II toxicities. CONCLUSIONS: Combination chemotherapy with CVD produced objective tumor responses in patients with advanced malignant pheochromocytoma/paraganglioma. In this 22-year follow-up there was no difference in overall survival between patients whose tumors objectively shrank and those with stable or progressive disease. However, patients reported improvement in symptoms, had objective improvements in blood pressure, and had tumor shrinkage that made surgical resection possible. The authors conclude that CVD therapy is not indicated in every patient with metastatic pheochromocytoma/paraganglioma, but should be considered in the management of patients with symptoms and where tumor shrinkage might be beneficial.