Posttreated POEMS Syndrome With Concurrent Follicular Lymphoma Revealed by F-18-FDG and Ga-68-Pentixafor PET/CT

A 59-year-old man with history of POEMS syndrome was found with a painless mass in the right neck for 9 months. In F-18-FDG and Ga-68-pentixafor PET/CT, there were multiple neck nodes and left inguinal nodes that showed intense F-18-FDG and Ga-68-pentixafor uptake. In addition, osteoblastic bone lesions with mild F-18-FDG and Ga-68-pentixafor uptake were noted in the pelvis, which was consistent with posttreated osseous involvement of POEMS syndrome. However, considering lymphoadenopathy with such intense F-18-FDG uptake is not usually seen in POEMS syndrome, the patient underwent biopsy of the right cervical nodes. The histopathology with immunohistochemistry confirmed follicular lymphoma.