An Incidental Finding of Extraosseous Uptake in Technetium 99m Methylene Diphosphonate Bone Scintigraphy: Uterine Leiomyoma

Abstract

We present the case of a 58-year-old, postsurgical breast cancer patient who was examined for routine controls at the Oncology Department of Namik Kemal University, Tekirdag, Turkey. She was referred to the nuclear medicine department for possible metastatic spread to the skeleton; 740 MBq of methylene diphosphonate tecnetium 99m ([Tc-99m] MDP) was injected intravenously, and 3 hours later a whole-body bone scan was performed. The whole-body bone scan showed no abnormal uptake associated with bone metastases, but in the anterior projection images, an area of mildly increased technetium 99m methylene diphosphonate uptake was seen in the right pelvic region. This appearance did not seem related to bone structures. When a more detailed history of this region was obtained, we learned of the patient's uterine leiomyoma. As a result of ultrasound and magnetic resonance imaging findings, the mildly increased tracer uptake in the right pelvic area on bone scintigraphy was consistent with a calcified uterine myoma. We concluded that a soft tissue concentration of labeled phosphates should always be kept in mind when interpreting whole-body bone scans.