SPECT imaging for breast cancer staging

Accurate staging in breast cancer, including tumour sizing and the assessment of nodal and distant metastases, is required in order to plan surgery and post-operative therapy. Medical imaging techniques have made an important contribution to the diagnosis of carcinoma of the breast and the evaluation of local, regional and distant metastases. The study is aimed at establishing certain aspects of the diagnostic importance and priority of single photon emission computed tomography (SPECT) imaging in breast cancer. SPECT was carried out just after planar scintigraphy and then after intravenous injection of different radiopharmaceuticals in 45 women with histologically confirmed post-operation breast cancer. In 21 patients under loco-regional control of the disease before and/or after surgery, planar mammoscintigraphy and SPECT were conducted after intravenous injection of Tc-99(m)-MIBI (methoxyisobutyl isonitrile) or Tc-99(m)-anti-CEA (carcinoembryonic antigen) monoclonal antibody (MoAb). Bone SPECT was carried out in 24 patients when whole body bone scintigraphy was unable to determine the exact localization of bone metastatic lesions in the skull, thorax and pelvis. The results suggest that SPECT with Tc-99(m)-MIBI and Tc-99(m)-anti-CEA MoAb has high sensitivity and improves the results of conventional planar scintigraphy for breast cancer detection. Breast SPECT is a preferable method for tumour and lymph node imaging because of the excellent separation of the deep breast structures from the myocardium in the left breast and of the right breast from the liver, thus improving the resolution of small, deep seated lesions. SPECT improves breast cancer staging, and determines the tumour, nodule and metastasis categories, which are important for the treatment strategy and prognosis of the disease.