Differential Diagnosis of a Solitary Bone Lesion Using SPECT/CT Method

Relevance: Radionuclide bone scan signs of lesions are not specific and require radiological identification. Hybrid tomographic technology is a combination of spatial distribution of radiopharmaceuticals and its anatomical binding. Thus, makes it possible to accurately identify the affected bone structure and also determine the nature of this changes (radiological anatomy). In cancer patients, SPECT/CT method allows to visualize tumor pathology in the bones, but also keeps to a minimum errors and other excessive examinations.Purpose: To demonstrate the most frequent diseases and conditions that simulate tumor lesions in bones on bone scan.Material and methods: We analyzed the results of examinations of 81 patients with various tumor diseases (2015–2020). Bone scan was performed in the whole body 3 hours later, after intravenous administration of 99mTc-phosphotech on a Symbia E, T2 (Siemens, Germany). SPECT/CT was performed after WB Bone Scan.Results: The most frequent reasons for the focal increased uptake of radiopharmaceutical were: reactive increase in metabolism and as a result additional mineral repair: deforming osteoarthritis, osteophytes; post‑traumatic and postoperative changes; fractures (osteoporosis and stress fractures); inflammatory processes; focal uptake due to the benign neoplasms of bones and dysplasia. Combination of highly sensitive but non-specific scintigraphy with highly specific computed tomography makes it especially useful in anatomically difficult areas.Conclusion: SPECT/CT reveals a direct pater of anatomical and structural abnormalities with changes in bone tissue metabolism in case of different injuries and minimizes a number of ambiguous conclusions. SPECT/CT in oncological practice greatly helps nuclear medicine physician in the differential diagnostic process and reduces time of examination for the patient.