Peripheral blood stem cell transplant for POEMS syndrome is associated with high rates of engraftment syndrome

Polyneuropathy, organomegaly, endocrinopathy, M protein and skin changes (POEMS) syndrome is a devastating syndrome, characterized by peripheral neuropathy, organomegaly, endocrinopathy, monoclonal plasma cells, skin changes, papilledema, volume overload, sclerotic bone lesions, thrombocytosis and high vascular endothelial growth factor (VEGF). High-dose chemotherapy with autologous peripheral blood stem cell transplantation (ASCT) ultimately yields excellent clinical responses, but there can be considerable peritransplant morbidity. We have treated 30 POEMS patients with ASCT at Mayo Clinic, Rochester. During transplant period, patients had high rates of fever, diarrhea, weight gain and rash (93%, 77%, 53% and 43%, respectively). Only 13% remained outpatient, and median time to discharge from hospital was transplant day 17 (range 0-175). Splenomegaly was the baseline factor that best predicted for a complicated peritransplant course. Depending on the definition used, ∼50% of patients satisfied criteria for engraftment syndrome. Earlier and more aggressive use of corticosteroids may be associated with less complicated post-transplant courses. Median overall survival has not been reached; the treatment-related mortality was 3%. In addition, important clinical improvements and reductions in plasma VEGF levels can occur in the absence of significant decrease in the monoclonal protein. Unraveling the mechanisms of the syndrome both in the context of ASCT and in general are challenges for the future.