Indium-111 leukocyte uptake in a patient with osseous metastatic Ewing's sarcoma

A case of increased uptake of In-111 labeled leukocytes in osseous metastasis from Ewing's sarcoma is presented. Bone scan and MRI findings were concordant with the indium scan, and biopsy confirmed Ewing's metastasis. Although relatively specific for infection, indium infrequently does demonstrate abnormal bone uptake in several malignancies. This case report is the first to describe indium uptake in osseous metastatic Ewing's sarcoma. Possible mechanisms of indium leukocyte localization are discussed.