Characterizing POEMS Syndrome with 18F-FDG PET/CT.

POEMS (polyneuropathy, organomegaly, endocrinopathy, M protein elevation, and skin changes) syndrome is a rare paraneoplastic syndrome caused by an underlying plasma cell disorder. The patients usually present with multisystemic involvement. Thus, we performed a study to investigate the role of (18)F-FDG PET/CT in characterizing POEMS syndrome.

Methods: Ninety-one untreated patients with proven or suspected POEMS syndrome were recruited to undergo (18)F-FDG PET/CT. Features of bone lesions, lymphadenopathy, hepatomegaly or splenomegaly, bone marrow, and serous cavity effusion were examined, and 15 patients were followed up with PET/CT scans 3 mo after therapy.

Results: Of the 90 patients diagnosed with POEMS syndrome, there were 140 (18)F-FDG-avid bone lesions. These lesions were frequently found in the pelvis, and most showed mixed characteristics. Four patients showed enlarged and (18)F-FDG-avid lymph nodes. Sixty-five patients had hepatomegaly or splenomegaly. Some of them had hypermetabolic spleen and bone marrow. Forty-six patients had serous cavity effusion. Five male patients had gynecomastia. Three months after therapy, (18)F-FDG-avid bone lesions showed decreased metabolism.

Conclusions: (18)F-FDG PET/CT is a useful tool for the evaluation of patients with suspected POEMS syndrome. (18)F-FDG PET/CT may contribute to the diagnosis, evaluation, and follow-up of patients with POEMS syndrome by providing systematic findings of bone lesions, lymphadenopathy, liver or spleen involvement, serous cavity effusion, and the metabolic status of the lesions.