AUTOLOGOUS PERIPHERAL-BLOOD STEM-CELL TRANSPLANTATION FOR MULTIPLE-MYELOMA - A REPORT OF 259 CASES FROM THE SPANISH REGISTRY

Between January 1989 and November 1995, 259 patients with multiple mye loma (MM), 22 stage I, 57 stage II and 180 stage III at diagnosis were treated with myeloablative high-dose therapy followed by autologous p eripheral blood stem cell (PBSC) transplantation. The median time from diagnosis to transplantation was 17 months (6-112), At the time of tr ansplant, 56 patients were in CR, 153 in PR, 25 were nonresponders and 25 had progressive disease. Mobilization of stem cells was performed with G-CSF alone in 141 cases, chemotherapy plus G-CSF in 65, chemothe rapy plus GM-CSF in 36 and chemotherapy alone in 17 patients, The cond itioning regimen consisted of high-dose melphalan alone in 96 patients , melphalan plus TBI in 73, busulfan plus melphalan in 56, busulfan pl us cyclophosphamide in 27 and cyclophosphamide plus TBI in seven, The median durations of neutropenia (> 0.5 x 10(9)/l) and thrombocytopenia (> 20 x 10(9)/l) were 12 (5-118) and 13 days (5-360), respectively, T ransplant-related mortality occurred in 11 patients (4%), Once a stabl e graft was achieved, 114 patients (44%) received maintenance treatmen t with recombinant alpha interferon (IFN-alpha). Among the 248 patient s evaluable for response 125 (51%) had a CR and 100 had a PR (40%). Th e median duration of progression-free survival (PFS) and overall survi val (OS) after transplantation was 23 and 35 months, respectively, Uni variate analysis showed that response status pretransplant, only one l ine of primary induction treatment and IFN-alpha maintenance treatment post-transplant significantly influenced OS. Female sex, pretransplan t responsive disease, and treatment with IFN-alpha post-transplant wer e the factors significantly influencing PFS, The conditioning regimen and method of stem cell mobilization had no significant impact on OS a nd PFS, On multivariate analysis the only independent factors associat ed with a longer survival were the number of chemotherapy courses prio r to autologous PBSC transplantation and the pretransplant response st atus, The present analysis from the Spanish Registry confirms the feas ibility of autologous PBSC transplantation in myeloma patients with a very low toxicity (4% toxic deaths), The high complete response rate a fter transplantation is encouraging, The best results are obtained whe n the procedure is performed early after the first line of induction t herapy and in patients with chemosensitive disease, Whether early high -dose therapy followed by autotransplantation in responding patients i s superior to conventional chemotherapy is currently being investigate d in prospective randomized studies.