Tc-99(m)-MIBI scintimammography in the evaluation of breast lesions and axillary involvement: A comparison with mammography and histopathological diagnosis

The aim of this prospective study was to determine the diagnostic value of prone lateral Tc-99(m)-MIBI scintimammography in the detection of primary b reast cancer and axillary lymph node involvement in patients with breast le sions. We evaluated 83 palpable and 22 non-palpable lesions in 77 consecuti ve patients with a clinically palpable mass and/or suspicious mammographic finding. Early and late scintimammograms were performed after the intraveno us injection of 740 MBq Tc-99(m)-MIBI. The overall sensitivity of both scin timammography and mammography in the detection of primary breast cancer was 94%. The overall specificity was 84% and 56% for scintimammography and mam mography respectively. In the patients with palpable masses, the sensitivit y of scintimammography was 97% and the specificity was 84%; in those with n on-palpable masses, the sensitivity was 35% and the specificity 100%. For t he detection of axillary lymph node involvement, the sensitivity and specif icity of scintimammography were 68% and 93% respectively. However, conventi onal mammography showed 37% sensitivity and 86% specificity. In conclusion, scintimammography is an accurate and clinically valuable tool for evaluati ng palpable and non-palpable breast abnormalities. In addition to its high sensitivity, it improves the specificity of mammography both in the evaluat ion of breast masses and in the detection of axillary involvement. ((C) 199 9 Lippincott Williams & Wilkins).