Expression of EGFR family and steroid hormone receptors in ductal carcinoma in situ of the breast

The expression of EGFR family and steroid hormone receptors was examined in a series of 40 cases of pure ductal carcinoma in situ (DCIS) of the breast by immunohistochemical staining of paraffin-embedded sections. Hematoxylin and eosin-stained sections were used to classify the tumors according to t he published criteria by Holland et al. (Holland R, Peterse JL, Millis RR, et al. Semin Diagn Pathol. 1994;11:167-180). Of the tumors 48% were immunor eactive for EGFR, 63% for c-erbB-2, 78% for c-erbB-3, 95% for c-erbB-4, 88% for estrogen receptor (ER) and 80% for progesterone receptor (PR). Statist ically significant association between histological grade (differentiation) and c-erbB-2 protein expression was seen (p < .001). In addition, expressi on of c-erbB-4 protein was associated with c-erbB-2 (p = .004), c-erbB-3 (p = .058), ER (p = .002) and PR (p = .004). It is concluded that c-erbB-2 ex pression in DCIS is associated with high-grade pathological features, and a higher c-erbB-2 expression is seen in DCIS than in invasive breast carcino mas. A possible association between extensive expression of c-erbB-4 and st eroid hormone receptors in proliferative and premalignant breast epithelial cells and the c-erbB-2 expression in DCIS and invasive breast carcinomas i s discussed.