Renal uptake of technetium-99m methylene diphosphonate following therapeutic radiation for vertebral metastases.

Radionuclide bone scans in two patients with breast cancer and concurrent chemotherapy treatment revealed increased band-like uptake of [99mTc]methylene diphosphonate along the medial upper renal cortex corresponding to the portions of the kidneys included within the radiation field. The latency of onset of abnormal uptake was 5 to 9 mo following completion of radiation in one patient, peaked near 13 to 14 mo for both patients, and returned to baseline after 20 to 27 mo. Transient serum creatinine level elevations were also detected. These findings suggest that transient subclinical renal impairment may occur and be detected on bone scans following inadvertent inclusion of renal cortex in radiation fields.