Prostatic calcifications detected on Tc-99m MDP bone scan mimicking bone metastasis.

Uptake of Tc-99m MDP tracer was noted within prostatic calcifications in a 48-year-old man with no known malignancy who underwent a three-phase bone scan for left knee and thigh pain. Routine anterior and posterior views of the pelvis demonstrated focal tracer uptake within the right pubic bone, which mimicked a metastatic lesion. Additional imaging showed the uptake to be extraosseous and localized within the prostate in a distribution similar to the extensive prostatic calcifications seen on the corresponding plain film and computed tomography examinations of the pelvis. This unusual presentation illustrates another potential artifact that may be present in scintigraphic bone imaging of the pelvis.