Activity of bortezomib (B) in plasma cell dyscrasia (PCD) with POEMS-like syndrome

Abstract

e19564 Background: POEMS (polyneuropathy, organomegaly, endocrinopathy, m-protein, and skin changes) syndrome is a rare multi-system disorder associated with PCD. Although several reports revealed significant clinical benefit of IMIDs in POEMS syndrome cases that are not transplant candidates, no such published reports of B in this disease were found. Methods: We report the first case of PCD with POEMS like syndrome in addition to pulmonary hypertension, secondary right heart failure, and membranoproliferative glomerulonephritis that was successfully treated with single agent B. After presenting with the aforementioned signs and symptoms, a 64 year old white man, was diagnosed with PCD (bone marrow plasma cells 15%, IgG-λ, mild-moderate anemia, normal PET/CT, normal Cr and Ca) with ISS stage III. Due to being high risk for thromboembolic events, he was started on single agent B at 1.3mg/m2 days 1,4,8,11 Q21 days (cycles 1–4) which was reduced to 1.0mg/m2 days 1,4,8,11 Q21 days (cycles 5–6) due to grade 1 thrombocytopenia and neuropathy. This was followed by 3 maintenance cycles of 4 out of 5 weekly 1.0mg/m2. Results: Patient's breathing was subjectively better after cycle#1 despite experiencing side-effects from his pulmonary hypertension medications which had to be held and subsequently improved back to his baseline by cycle#4. By cycle#2, he was found to be in nCR with complete normalization of his bone marrow and serum electrophoresis by the end of therapy. He has been in nCR for almost 12 months so far. By cycle#3 his Raynaud's syndrome was significantly better with less dysesthesia which completely resolved by cycle#6. Conclusions: This case demonstrates for the first time the significant activity of B as a single agent in PCD with POEMS like syndrome. Further evaluation of the role of B as a first line agent in this disease, whether as single agent or in combination, is warranted. [Table: see text]