Hormone receptors expression in phyllodes tumors of the breast.

OBJECTIVE

To ascertain the hormonal receptor profiles of the epithelial and stromal components of phyllodes tumors (PTs) and determine their relationship with stromal proliferation.

METHODS

Eighty-two PTs (50 benign, 22 borderline, and 10 malignant) were studied. Automated immunohistochemical staining for estrogen receptor (ER)-alpha and -beta, progesterone receptor (PR), androgen receptor (AR), and Ki-67 was performed using tissue microarray blocks, and their expression was assessed in both the stromal and epithelial components.

RESULTS

The epithelial component demonstrated the expression for ER-alpha (45.6%, 36 of 79), ER-beta (37.2%, 29 of 78), PR (91.1%, 72 of 79), and AR (10.1%, 8 of 79). The stromal component was positive for ER-beta (29.3%, 24 of 82) only. The epithelial expression of ER-beta was found to be significantly correlated with the epithelial expression of AR (r = 0.352, p = 0.002). No association was found between hormone receptor expression and PT tumor grade. Stromal Ki-67 expression was statistically correlated with epithelial ER-beta, epithelial AR, and stromal ER-beta expression.

CONCLUSIONS

Epithelial and stromal ER-beta and epithelial AR expression in PTs was correlated with the proliferative rate in the stromal component. Immunohistochemical examination of ER-beta and AR may have some impact on the postoperative management of patients with PTs.