technetium-tc-99m-medronate and Gastrointestinal-Stromal-Tumors

This case demonstrates extraosseous 99m-technetium methylene diphosphonate (Tc-99m MDP) accumulation from a gastrointestinal stromal tumor. A 75-year-old woman underwent a temporal bone CT for conductive hearing loss that showed sclerosis in the right occipital condyle. Follow-up Tc-99m MDP bone scan for osseous metastases instead showed a mass-like extraosseous accumulation of Tc-99m MDP in the anterior left upper quadrant. Differential diagnoses included gastric cancer, lymphoma, metastatic melanoma, systemic hypercalcemia, or heterotopic mesenteric ossification. Contrast CT showed a well-circumscribed mass arising from the stomach, and subsequent pathology confirmed gastrointestinal stromal tumor. These tumors rarely can contain osteoclast-like giant cells and should be considered for extraosseous Tc-99m MDP accumulation.

Topics: Aged; Bone and Bones; Female; Gastrointestinal Stromal Tumors; Humans; Incidental Findings; Radionuclide Imaging; Technetium Tc 99m Medronate; Tomography, X-Ray Computed; Whole Body Imaging