Diffuse bone marrow uptake on F-fluorodeoxyglucose positron emission tomography/computed tomography with copper-deficiency anemia.

A 59-year-old man with pancytopenia underwent 18F-fluorodeoxyglucose positron emission tomography/computed tomography for suspected carcinomatosis. The scan revealed diffuse bone marrow uptake, prompting further investigation. Bone marrow analysis revealed no malignant cells; however, erythroblasts with cytoplasmic vacuolization were observed.