Demonstration of active osteoarthropathy at In-111 Zevalin scan in a patient with non-Hodgkin's lymphoma

1067 Learning Objectives 1. To review the normal and abnormal pattern of In-111 Zevalin biodistribution, particularly caused by active osteoarthropathy (AO). 2. To discuss possible consequences of AO on the 90Y-Zevalin treatment in patients with CD20 receptor-positive non-Hodgkin’s lymphoma(NHL). 90Y-Zevalin is an effective treatment for CD20 receptor-positive NHL. It has been approved for patients who achieve a partial or complete response to first-line chemotherapy, or have relapsed or refractory, low-grade or follicular B-cell NHL. We present a 70-year-old woman with stage IIIa follicular B-cell lymphoma who completed chemotherapy with R-CHOP in 4/2008, and achieved complete remission initially. However, she showed evidence of early relapse in 9/2008 seen as FDG avid lymph nodes in the mediastinum, abdomen and pelvis. Subsequent pleurectomy and mediastinal biopsy confirmed B-cell lymphoma. Bone marrow biopsy was negative. She was then treated with R-CMOPP. There was partial treatment response but early relapse occurred based on FDG PET/CT findings in 3/2009. An indication for Y-90-Zevalin was made. On pre-treatment In-111-Zevalin scan, intense tracer activity in the right shoulder joint was noticed besides the physiologic activity in the large vessels, cardiac ventricles, liver and spleen. The right shoulder uptake was 3.3% of the whole body activity based on geometric mean calculations. This finding correlated with intense FDG uptake and osteoarthropathy changes on CT. The patient complaint of right chronic shoulder pain, and the clinical diagnosis of AO was made. Given the relatively low uptake in the right shoulder, the patient was treated as scheduled with a full dose regimen of 27 mCi of Y-90 Zevalin. In this exhibit, normal and abnormal biodistribution of In-111 Zevalin including this one case of OA will be presented and their impact on efficacy Y-90 Zevalin treatment will be discussed