Instituition: Hospital Nossa Senhora das Graças
OBJECTIVES: To evaluate the impact of breast magnetic resonance imaging (MRI) in preoperative patients with early breast cancer and candidates for oncoplastic surgery. METHODS: This is a prospective study, 60 patients diagnosed with early breast cancer, performed by clinical, radiological (mammography and US) and pathological examination. All patients were submitted to preoperative MRI and were evaluated for changes in surgical planning for mastectomy or maintaining a conservative approach. RESULTS: Of 60 patients, 29 were detected (48.3%) with additional lesions. Among these, 16 (55%) were multifocal, 1 (3.4%) was a multicenter, 5 (17%) were in the contralateral breast and 9 (31%) had tumor extent greater than 10mm on MRI when compared with mammography and US. MRI was the imaging test closer to the real tumor size. Of the 60 patients who underwent MRI, 12 (20%) underwent mastectomy. The indication of this procedure in this subset of patients was due to the fact that 10 (83.0% – from mastectomy group) were multifocal, 1 (8.3%) was multicentric and 3 (25%) had cancer in the contralateral breast MRI. Among the 12 mastectomies performed, 83% were indicated by disproportion between the size of the breast and the tumor size, coupled with the presence of multifocality and / or multicentric and family history. The positive margin rates were 5% in the total study population and 3.4% in patients who were detected additional lesions on MRI. CONCLUSION: The local staging with the MRI examination translates into better surgical planning when associated with the OP, with better oncological and aesthetic-functional result. Keywords: Magnetic Resonance, Conservative surgery, Oncoplastic