Super-superscan on a bone scintigraphy.

Superscans on bone scintigraphy have been described mostly in metastatic and metabolic bone diseases, with different patterns and appearances of radiotracer uptake. This is a report of bone scintigraphy demonstrating superimposed metastatic and metabolic superscan in a patient with prostate cancer, who subsequently developed renal osteodystrophy. Two years after the first bone scintigraphy showing multiple metastases, the patient developed renal insufficiency, hyperphosphoremia, and hypocalcemia. Repeat bone scintigraphy demonstrates significantly different appearance from that of the first study. Caution should be exercised when interpreting a bone scintigraphy in patients with known malignancy and coexisting renal failure or metabolic bone disease. Superimposed appearances of metastatic and metabolic superscan may obscure recognition of osseous metastases.