Alternating combination chemotherapy COP (cyclophosphamide, vincristine, prednisone) and MP (melphalan, prednisone) in multiple myeloma: a multicenter phase II study (JCOG8906). Lymphoma Study Group of the Japan Clinical Oncology Group

BACKGROUND: The main form of cytotoxic treatment for multiple myeloma (MM) is conventional dose chemotherapy at present. METHOD: Between November 1989 and December 1991, a multicenter phase II study of alternating conventional dose combination chemotherapy (CCT) with COP (cyclophosphamide, vincristine, prednisone) and MP (melphalan and prednisone) to evaluate its clinical usefulness for overt MM patients was conducted by the Lymphoma Study Group of the Japan Clinical Oncology Group (JCOG). RESULTS: Eighty-one previously untreated patients were enrolled in the study. For 69 eligible patients, the response rate was 50.7% [95% confidence interval (CI) 38.4-63.0%]. The median survival time was 38.5 (95% CI 32.0-44.4) months. The survival rate at 3 and 5 years was 50.7 and 27.3%, respectively. Grade 4 toxicity by the criteria of the World Health Organization consisted of anemia in eight patients, leucocytopenia in three, cardiac in one and hepatic in two, but there was no treatment-related death. CONCLUSION: The COP-MP regimen for overt MM is thought to be one of the effective CCTs according to the results of the present phase II study.