Efficacy and Long-Term Outcomes of Autologous Stem Cell Transplantation in POEMS Syndrome: A Nationwide Survey in Japan.

POEMS syndrome is a rare plasma cell dyscrasia presenting with polyneuropathy, λ-type M protein, vascular endothelial growth factor elevation, and systemic manifestations. The standard treatment has not been established, but autologous stem cell transplantation (ASCT) has exhibited effectiveness in this syndrome. However, the efficacy and long-term outcomes of ASCT have not been systematically studied. To clarify the efficacy and long-term outcomes of ASCT-treated patients in Japan, we performed a multicenter retrospective study assessing the clinical course of patients registered to the Japan Society for Hematopoietic Cell Transplantation Transplant Registry Unified Management Program (TRUMP) database. Between January 2000 and December 2011, 95 patients (58 men) were registered to the TRUMP database with a median age of 53 years (range, 28 to 72). The conditioning regimen was melphalan in 93 of 94 patients (99%), and 69 patients (74.2%) received a melphalan dose ≥ 200 mg/m2 . The median CD34 cell dose was 2.47 × 106 /kg (range, .31 to 20). After ASCT, patient performance status was dramatically improved (Eastern Cooperative Oncology Group performance status 0 to 1: 20.0% versus 71.6%, P < .0001). Over a median follow-up of 46.6 months 10 patients died, and 5-year overall survival was 88.8% (n = 95). Progression-free survival at 3 years was 78.3% (n = 70; median follow-up, 54.4 months). These data support the promising role of ASCT in patients with POEMS syndrome for both prolonging survival and improving quality of life. However, disease recurrence remains a major issue for long-term survivors.