[Current status of treatment for multiple myeloma]

The current status of treatment for multiple myeloma was reviewed. Recently, the response rate and survival for patients with multiple myeloma have improved with an introduction of combination chemotherapy. The addition of prednisolone to the regimen including alkylating agents clearly improved a response rate by 20% and extended survival by approximately 5 months. More recently, the use of multiple-drug combinations, such as VMCP and VMCBP schedules, seems to yield the best response rate. However, current improvements in survival of myeloma patients cannot be attributed fully to improved chemotherapy on the basis of the findings that the annual incidence and the number of patients with low tumor burden increase progressively, and the patients in the early stage of the disease have a high value for the incidence of long survival. Furthermore, earlier diagnosis, a low frequency of severe renal failure, and superior control of infections may likely influence the duration of survival. In order to cure the malignant tumor disease, it is necessary to eradicate every viable tumor cell in the host. Unfortunately, the most recently utilized combination chemotherapy has shown little evidence of permanent cure of multiple myeloma, even in patients with low tumor burden, i.e., effective treatment with currently available agents causes only an initial 1-2 log fall in the total body myeloma cell mass and an additional treatment does not reduce the residual tumor cell mass. Therefore, further studies of new drugs with major activity against plasma cell myeloma are expected.