Characterization of suspicious breast lesions with dynamic contrast enhanced MRI in comparison to conventional mammography and ultrasonography

Abstract

SUMMARY AND CONCLUSION B reast cancer is the most common malignant tumor among women. The purpose of all diagnostic modalities in breast cancer is early detection and proper diagnosis, which has its major impact on further management and prognosis. X-ray mammography is still considered the first examination tool in diagnosis of breast disease worldwide. The overlap in the mammographic appearance of benign and malignant lesions as well as dense breast tissue especially in young patients necessitates the presence of problem solving complementary studies. Ultrasound has been established as a complementary tool for mammography because of long experience with its use, accessibility, relatively low cost and the opportunity it affords for real time guidance of aspiration or needle biopsy however, its operator dependence nature remains its main limitation. Because investigators of breast MR imaging have reported higher sensitivities and specificities for MR imaging compared with those for mammography, it has been suggested that MR imaging could be used to further characterize indeterminate lesions detected at mammography, ultrasound or physical examination. The current study evaluated the role of MRM in suspicious breast lesions diagnosed by mammography and ultrasound examination. We conducted a study in Almostaqbal and King Abdulaziz hospitals included 33 patients with 36 breast lesions. Cases were referred from the surgical clinics. All patients underwent mammographic and ultrasonographic examinations with classification of their findings according to Breast Imaging Reporting and Data System (BI-RADS). Then all patients were referred for further MRI examination. The findings of each modality were correlated with histopathological results. In our study the overall sensitivity of mammography, US and MRM was 66.7%, 86.7% and 98.6% respectively. Their specificity was 91.5%, 87.8% and 78.8 % respectively. MRI was the most sensitive imaging method for detection of cancer but with limited specificity due to overlap in features of benign and malignant lesions. Finally, we conclude that breast MRI is no longer an experimental modality, but has attained a solid position in the diagnosis and workup of (suspected) breast lesions. In case of indeterminate breast lesions, the diagnostic accuracy of MRI is superior to mammography and ultrasonography. Our results indicate that the sensitivity of breast imaging can be increased by complementary use of MRI. For patients in whom the status of breast lesion remains unclear, MRI, though most expensive among all other complementary diagnostic modalities, it reduces the number of unnecessary biopsies and diagnostic ambiguities.