Efficacy of 3D-MR mammography for breast conserving surgery after neoadjuvant chemotherapy.

BACKGROUND

One of the main roles of neoadjuvant chemotherapy for breast cancer is to shrink large tumors to increase patient eligibility for breast conserving surgery. Three dimensional MR Mammography (3D-MRM) can detect tumor extension more accurately compared with mammography and Ultrasonography (US). Therefore, the shrinkage pattern observed on 3D-MRM was analyzed with regard to several pathological factors.

METHODS

A total of 27 breast cancer cases were examined by 3D-MRM before and after neoadjuvant chemotherapy. The volume reduction and shrinkage patterns were assessed and compared with the pathological diagnosis.

RESULTS

There were two shrinkage patterns. Twelve of 25 evaluable breast cancers (48%) showed a concentric shrinkage pattern while 13 cases (52%) showed a dendritic shrinkage pattern. The cases with concentric shrinkage were good candidates for breast conserving surgery, But tumors showing dendritic shrinkage often had positive margins necessitating mastectomy. Pathologically, tumors with a papillotubular pattern, Estrogen receptor (ER) positivity, low nuclear grade and c-erbB 2 negativity tended to show dendritic shrinkage.

CONCLUSIONS

3D-MRM is a useful modality for evaluating whether breast conserving surgery can be safely done in the neoadjuvant setting.