Retrospective Study Assessing the Role of MRI in the Diagnostic Procedures for Early Breast Carcinoma: A Correlation of New Foci in the MRI with Tumor Pathological Features.

Abstract

Purpose: To analyze the role of MRI in the detection of additional disease and the need to perform additional biopsies in early breast carcinoma patients. In addition, to correlate the detection of new foci with tumor pathological features.Methods: Early breast carcinoma patients that had undergone a MRI as well as a mammography as diagnostic procedures were included in the study. The following pathologic features were studied: carcinoma type, histological grade, estrogen (ER)/progesterone (PR) receptors, HER2 and Ki67. HER2 status was established by FISH, while ER, PR and Ki67 status were established by inmunohistochemistry. Univariate analysis was conducted to ascertain significant correlation among detection of new foci and each of the tumor pathological features.Results: To date, data from 98 patients have been analyzed: median age 49 years (range: 35-79); carcinoma type: a) infiltrative ductal carcinoma (n=73, 74%), b) infiltrative lobular cancer (n=13, 13%), c)ductal carcinoma in situ (n= 6, 6%); amplified HER2 (n=18, 18%); grade III (n=33, 33%);Ki67 ≥ 25%(n=33, 33%); positive ER and PR (n=78, 79%); triple negative tumors (n=8, 8%). MRI detected additional disease in 38 cases (39%) that led to an additional biopsy in 20 cases (20%). Thirty-nine patients (39%) underwent mastectomy. A statistically significant correlation was established between the finding of new foci in MRI and high proliferative tumors through the biomarker Ki67 (cutoff ≥ 25%) (p<0.005). No other statistically significant correlation was established with any of the other pathological features analyzed.Conclusion: In patients diagnosed with early breast cancer, MRI detected the presence of additional disease in 39% of the cases, requiring an additional biopsy in 20% of the cases. Tumors with high proliferative index were significantly correlated with the detection of new foci in MRI. An update of the results will be presented at the symposium. Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 4018.