CLINICOPATHOLOGICAL ANALYSIS OF AMPHIREGULIN AND HEREGULIN IMMUNOSTAINING IN BREAST NEOPLASIA

We observed no association between neoplastic epithelial immunostainin g for either amphiregulin (AR) or heregulin (HRG) and presence of ER, EGFR/ERBB-2 overexpression, nodal status, or disease recurrence in 34 breast carcinomas. However, stromal cell staining for both correlated with outcome; 29% of stromal cell AR circle minus cases recurred vs. 8 5% for AR circle plus cases (p = 0.001), and 41% of stromal cell HRG c ircle minus cases recurred vs. 82% of HRG circle plus cases (p = 0.01) . We conclude that both HRG and AR have significant biologic roles in breast carcinoma growth or progression via mediation of host-tumor int eractions which favor aggressive tumor behavior.