A prospective phase II study of low dose lenalidomide plus dexamethasone in patients with newly diagnosed polyneuropathy, organomegaly, endocrinopathy, monoclonal gammopathy, and skin changes (POEMS) syndrome.

Polyneuropathy, organomegaly, endocrinopathy, monoclonal gammopathy, and skin changes (POEMS) syndrome is a rare plasma dyscrasia without standard treatment. This phase II prospective trial evaluates the safety and response of 12 cycles of low dose lenalidomide (10 mg) plus dexamethasone (Rdex) in patients with newly diagnosed POEMS syndrome. Forty-one patients (28 men) were enrolled and the median age at diagnosis was 49 years (range, 21-70 years). Twenty-one patients (46%) achieved complete hematologic response and the neurologic response rate was 95%. The median serum vascular endothelial growth factor (VEGF) declined from 5155 pg/mL (range, 534-14 328 pg/mL) to 832 pg/mL (95-6254 pg/mL) after therapy. The overall VEGF response rate was 83%, and the median time to response was 2 months, with a mean VEGF reduction of 43% at the first month. In terms of clinical response, Rdex substantially relieved extravascular volume overload, organomegaly, and pulmonary hypertension. No treatment-related deaths occurred and no patients suffered from lenalidomide-related grade 3 or above adverse events. After a median follow-up of 34 months, median overall survival (OS) and progression-free survival (PFS) were not reached, with an estimated 3-year OS and PFS of 90% and 75%, respectively. In conclusion, Rdex was active with high hematologic, VEGF and organ response rate and well tolerated for patients with newly diagnosed POEMS syndrome. This trial was registered at www.clinicaltrials.gov as #NCT01816620.