ABSTRACT
BACKGROUND: Technetium-99m sestamibi scintimammography (SMM) has been shown to be a useful diagnostic test in the detection of breast cancer, and the receiver operating characteristic (ROC) curve analysis provides detailed information about the diagnostic test. A ROC curve analysis was performed to evaluate the feasibility of Tc-99m sestamibi quantitative scintimammography (qSMM) for differentiating malignant from benign breast lesions. METHODS: Prone anterior, lateral planar, and supine SPECT imagings were performed on 75 female patients (mean age=43.4 yr) with breast masses (size> or =0.8 cm) after intravenous injection of 30 mCi of Tc-99m sestamibi. 45 malignant and 30 benign lesions were histologically proven. Three regions of interest (ROIs) were drawn over designated areas: lesion (L), normal breast opposite to the lesion (NL), and right chest wall (CW). L/NL and the L/CW ratios on both the SPECT and the planar images were analyzed. RESULTS: ROC curve analysis revealed that planar L/NL ratio and the SPECT L/NL and L/CW ratios provide better diagnostic accuracies for detecting breast cancer than the planar L/CW ratio did (p<0.05). From the qSMM (mean), which was an arithmetic mean of the planar L/NL, ratio the SPECT L/NL ratio and the SPECT L/CW ratio, the sensitivity, the specificity, the positive predictive value, the negative predictive value, and the accuracy were 84%, 77%, 84%, 77%, and 81%, respectively. Presence of axillary lymph-node metastasis showed a higher qSMM (mean) value (4.09 {n=17} vs 3.09 {n=28}, p=0.06). CONCLUSIONS: qSMM (mean) is a useful objective method for differentiating malignant from benign breast lesions.