Radiopharmaceuticals are a well-known form of ionizing radiation, emitting
gamma photons. They are used in clinical routine for cancer patients; nuclear medicine
utilizes oncotropic cationic complexes such as 99mTc-Sestamibi/Tetrofosmin
(MIBI/TF); radioiodine 123I /131I; radiolabeled somatostatin (SST) derivatives 111In-
Octreoscan/99mTc- Tektrotyd; diphosphonates 99mTc-MDP /HEDP; nanoparticles 99mTc-
Nanocoll and etc. The tracer accumulation to tumor cells is dependent on blood
perfusion, biodistribution, cellular proliferation, oxygen consumption, receptor status,
and other factors in different tumors. Besides multiple imaging methods for evaluating
malignant diseases, new hybrid SPECT/CT imaging can provide accurate diagnostic
information about the presence and staging of neoplastic diseases as well as unique
biological characteristic information, such as quantification of cellular proliferation or
SST-receptor status. The SPECT component of the hybrid SPECT/CT images provides
information about the functional activity of the primary neoplastic tumor and the
secondary metastatic lesions, whereas the CT component is needed for the anatomy of
the “hot” lesions seen in the nuclear medicine modality. This may result in a reduced
number of false-positive and false-negative results and increased sensitivity and
specificity of the nuclear medicine studies. The SPECT/CT examinations may find a
different clinical value in oncology. Combined SPECT/CT images enable discovering
primary occult tumors, visualizing local or distant metastases for accurate NM-staging,
and evaluating therapy response. SPECT/CT images can be used for radiotherapy
planning to delineate target and functional gross tumor volumes.
Keywords: 123I/131I, 123I/131I -MIBG, 111In-Octreoscan, 99mTc-MDP/HEDP, 99mTc- Nanocoll, 99mTc-Sestamibi, 99mTc-PSMA, 99mTc-Tektrotyd, 99mTc-Tetrofosmin, Neuroendocrine tumors, Prostate cancer, Sentinel lymph nodes, SPECT/CT, Thera(g)nostics, Thyroid cancer.
