Factors associated with cystosarcoma phyllodes of the breast after core needle biopsy identify cellular fibroepithelial lesion.

Abstract

e11518 Background: Cystosarcoma phyllodes (CP) represents less than 1% of all breast neoplasms and can mimic fibroadenoma on core needle biopsy (CNB). When CNB specimens suggest CP, excision is recommended. However, the treatment of fibroepithelial lesions with cellular stroma on CNB is controversial as a large percentage may prove to be fibroadenoma. We sought to identify clinicopathologic factors that were associated with CP after CNB suggested cellular fibroepithelial lesion. Methods: A retrospective database identified 65 patients over a 10 year period that underwent surgical resection of the breast after CNB identified cellular fibroepithelial lesion. An additional 21 patients with CNB findings of fibroadenoma eventually underwent resection of a CP and were included in the analysis. Patients were grouped by pathologic diagnosis at surgical resection as either fibroepithelial lesion or CP. Clinical and pathologic data were analyzed to look at differences between groups. Results: Forty-three patients were diagnosed with a fibroepithelial lesion on both CNB and surgical resection and 43 patients were diagnosed with either fibroepithelial lesion or fibroadenoma on CNB and CP on surgical resection. There was no significant difference in age between the groups (39 vs. 35.3 years, NS), however, the mean radiographic size was larger in the CP group (2.5 vs. 4 cm, p<.05). Compared with African-American, Caucasian and Asian race, Hispanic race was associated with CP on final pathology (p<.05). Conclusions: If cellular fibroepithelial lesion is identified on CNB of the breast in a woman in the fourth decade of life, larger size and Hispanic race are associated with the presence of CP. These results may help guide clinicians in treatment planning for this subgroup of patients.