Increasing accuracy of detection of breast cancer with 3-T MRI

The purposes of this study were to assess the sensitivity and specificity of 3-T MRI compared with those of mammography and sonography in the evaluation of breast cancer and to evaluate the results in light of previously published data obtained with 1-T and 1.5-T systems.

A retrospective review was conducted with data on 434 women (mean age, 53 years) who underwent MRI evaluation of the breasts (n = 868). Results obtained from 3-T MRI, mammographic, and sonographic examinations of all patients were compared. Sensitivity, specificity, and predictive values were calculated, and statistics were analyzed with the chi-square test.

The sensitivities of MRI, mammography, and sonography in the detection of malignancy were 100%, 81.8%, and 86.4%, and the specificities were 93.9%, 99%, and 98.1%. The specificity of MRI increased from 92.8% to 94.5% over the course of the study (2006-2007). Compared with mammography (p < 0.001) and sonography (p = 0.001), MRI depicted a significantly higher number of malignant tumors of the breast. There was no significant difference between mammography and sonography (p = 0.095). Results were compared with those in earlier reports in the literature.

MRI at 3 T is more sensitive than mammography and sonography in the detection of breast cancer and the characterization of small lesions (reaching 4 mm) but has lower specificity. Compared with the results of 1-T and 1.5-T MRI in the literature, 3-T MRI has higher sensitivity in the detection of breast cancer with no significant difference in specificity.