Incidental Detection of Skeletal Metastases on 99mTc-DTPA Renography

We present the case of a 53-year-old man with left hydroureteronephrosis who underwent Tc-DTPA renography for functional assessment of bilateral kidneys. Tc-DTPA renography of the patient showed diffusely increased extrarenal Tc-DTPA uptake in the visualized lumbosacral vertebrae and in the pelvic bones, on the blood flow and functional phase of the renography, which was suggestive of disseminated skeletal disease. Subsequent MRI lumbosacral spine and F-FDG PET/CT revealed extensive skeletal metastases corresponding to the increased extrarenal Tc-DTPA uptake in the lumbosacral vertebrae and the pelvic bones from primary left lung mitotic lesion.