Hypothesis Preoperative magnetic resonance imaging (MRI) mammography, after positive fine-needle aspiration (FNA) or stereotactic biopsy, may alter surgical management of the index breast cancer.
Design Review of MRI mammograms compared with conventional mammograms and clinical examination.
Setting Rural community hospital.
Patients Consecutive cohort of 27 patients with breast cancer who underwent prebiopsy or preoperative MRI mammography.
Intervention Surgical management of breast cancer.
Main Outcome Measure Change in surgical management prompted by findings on MRI mammography.
Results Prebiopsy or preoperative MRI mammography changed surgical management in 13 (48%) of 27 patients with breast cancer by discovering multicentric cancers or more extensive cancer. Of the 27 patients, 9 with positive FNA biopsy results of palpable masses underwent preoperative MRI; in 6 of the 9, ipsilateral multicentric cancers or more extensive cancer was discovered that necessitated mastectomy rather than breast conservation. Eighteen of the 27 patients had category 4/5 mammograms. Ten of these patients had stereotactic biopsies followed by MRI; 4 of the 10 had changes on the MRIs that required mastectomy rather than breast conservation. Eight of the 27 patients had MRI before stereotactic biopsy; 3 of the 8 had MRI abnormalities that required mastectomy. One patient had contralateral, multicentric cancers not seen on conventional mammography, necessitating bilateral mastectomies.
Conclusions We recommend that patients who desire breast conservation undergo MRI mammography before biopsy of a category 4/5 mammogram or immediately after a positive FNA biopsy result of a palpable mass.
