March 1st 2003
The use of high-dose chemotherapy and autologous stem cellsupport in the past decade has changed the outlook for patients withmultiple myeloma. In newly diagnosed patients, complete remissionrates of 25% to 50% can be achieved, with median disease-free andoverall survivals exceeding 3 and 5 years, respectively. Despite theseresults, autologous transplantation has not changed the ultimatelyfatal outcome of the disease, as there is no substantial evidence of“cure” in most published studies. An additional high-dose chemotherapycourse (with tandem transplants) appears to improve progressionfreesurvival, although the effect is not discernible until 3 to 5 yearsposttransplant. The recent reports of tandem autologous transplant formaximum cytoreduction followed by nonmyeloablative allogeneictransplant for eradication of minimal residual disease appears promisingand deserve further investigation. A central issue of tandemtransplants, whether they involve autologous or allogeneic transplants,revolves around defining the subsets of patients who will benefitfrom the procedure. Good-risk patients (defined by normal cytogeneticsand low beta-2–microglobulin levels), especially those who achievea complete or near-complete response after the first transplant, appearto benefit the most from a second cycle. High-risk patients (defined bychromosomal abnormalities usually involving chromosomes 11 and 13and high beta-2–microglobulin levels) whose median survival aftertandem transplant is less than 2 years should be offered novel therapeuticinterventions such as tandem “auto/allo” transplants. Until theefficacy and safety of this procedure is fully established, it should belimited to high-risk patients.