Scintigraphic Evaluation of Metastatic Osteosarcoma The Importance of SPECT Bone Scintigraphy and Correlative Imaging

A 31-year-old man with a history of osteosarcoma and prior resection of the left distal femur had an acute onset of hemoptysis. Planar skeletal scintigraphy with Tc-99m MDP showed an area of increased uptake in the region of the posterior left 8th rib, suspicious for a metastatic lesion. Chest x-ray showed a pulmonary nodule in the left lower lobe. Rib x-rays showed no metastases. Because the patient was scheduled for a thoracotomy to remove the lung lesion, original plans called for removal of the left eight posterior rib as well. Repeat bone scintigraphy, this time using SPECT, clearly showed that the lesion identified on planar imaging was indeed in the pulmonary parenchyma and not in the rib, representing"shine through." This case shows the importance of correlative imaging as well as SPECT bone scintigraphy when findings on the planar study are not clear, and it may affect the patient's surgical management.