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

Abstract A 59-year-old man with history of POEMS syndrome was found with a painless mass in the right neck for 9 months. In 18 F-FDG and 68 Ga-pentixafor PET/CT, there were multiple neck nodes and left inguinal nodes that showed intense 18 F-FDG and 68 Ga-pentixafor uptake. In addition, osteoblastic bone lesions with mild 18 F-FDG and 68 Ga-pentixafor uptake were noted in the pelvis, which was consistent with posttreated osseous involvement of POEMS syndrome. However, considering lymphoadenopathy with such intense 18 F-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.