Clinical Application of SPECT-CT in Breast Cancer

Radiopharmaceuticals used in standard nuclear medicine for patients with breast cancer are a well-known source of ionizing radiation, emitating gamma-photon particles: tumorotroponin cationic complexes such as 99mTc-Sestamibi/ Tetrofosmin (MIBI/TF); radiolabelled somatostatin analogues 111In-Ocrteoscan/99mTc-Tektrotyd; 99mTc-MDP; 99mTc-Nanocoll and etc. The intensive tracer uptake of the different radiopharmaceuticals depends on the blood perfusion and their biodistribution, the proliferative activity of the tumor cells, the oxygen consumption, receptor status, and other factors of different tumors. For example the tumorotroponin cation complex 99mTc-MIBI concentrates in the mitochondria while 99mTc-TF uptake is also in the cytosol, due to the fact, that in active proliferative cells they are found in bigger quantity. The introduction of the modern SPECT-CT camera to the clinical practice in the past 10 years dramatically improved the quality of the planer and SPECT images. The SPECT-CT camera is an integrated multimodal apparatus, containing CT scanner and SPECT γ-camera with a single bed for the patient, which makes it possible to obtain the CT scan. SPECT scan and the combined or "fusion" SPECT-CT images. This new technology makes possible the visualisation of lesions with a size <10 mm, due to its higher separation ability of the detecting apparatuses, and the correction of dispersed x-rays through interactive methods.