Abstract P2-02-09: The Effect of Breast-MRI in Work-Up of Primary Operable Breast Cancer

Abstract

Abstract Background: Breast magnetic resonance imaging (MRI) is becoming an often-utilized examination in the preoperative planning for breast cancer. However, it is not yet accepted as a routine examination for all breast cancer patients due to the lack of data regarding whether breast MRI has any effect on recurrence or survival. Aim: The aim of this study is to evaluate the effect of MRI on surgical management in operable breast cancer. Methods: From April 2008 till January 2010 consecutive primary operable breast cancer patients had a preoperative breast-MRI in addition to regular mammography and ultrasonography. Additional lesions newly found by MRI were evaluated with a target ultrasound and if needed biopsied. Moreover MRI tumor size was compared to mammographic and ultrasonographic tumor size. Blinded for MRI results and the performed surgical plan, surgical management based on traditional radiological work-up was determined retrospectively by 2 surgeons. Change of surgical plan by MRI was subsequently analysed. Accuracy of MRI based surgical plan was evaluated by comparing definitive pathology. Results Hundred ninety eight consecutive patients were analyzed. Median age was 59 years (23-82). Additional ipsilateral and contralateral suspicious lesions were detected by MRI in 53 patients (27%). Twenty two patients had additionally target-ultrasonography: 5 lesions were not found, 4 lesions had benign aspect. Five out of 13 biopsied patients had second breast cancer, 3 patients had contralateral breast cancer and 2 patients had multicentric breast cancer. In 31 patients no further evaluation was performed because the new focus was supposed to be a satellite (n=12) or mastectomy was already chosen to be done (n=19). There was a change in surgical plan due to MRI results in 35 of 198 patients (18%), all of whom received more extensive surgery than previously planned: in 17 patients mastectomy was performed instead of lumpectomy, 15 patients had a more extensive lumpectomy. Three patients had contralateral surgery for breast cancer. In 24 patients (69%) MRI based surgical plan was confirmed by definitive pathology. In 11 patients MRI overestimated tumor size or misinterpreted a satellite lesion. Conclusion. Breast MRI contributes to a significantly change of surgical plan. However, false-positive findings are frequent. Therefore, in unselected primary operable breast cancer patients routine implementation of breast MRI is not right away justified. Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P2-02-09.