p53 protein expression, cell proliferation and steroid hormone receptors in ductal and lobular in situ carcinomas of the breast.

p53 and c-erbB-2 expression, and their correlation with cell proliferation and steroid hormone receptors, were investigated in 121 carcinomas, 23 lobular in situ carcinomas (LCIS), 74 intraductal carcinomas (DCIS) and 24 minimal invasive carcinomas. DCIS were classified according to the EORTC classification. All markers were measured immunohistochemically on paraffin sections. None of the LCIS, 9 DCIS and 9 minimal invasive cancers showed nuclear positivity for p53. A strong association between histological type and p53 expression was found. Proliferation rates correlated with p53 expression. c-erbB-2 positivity was found in 1 LCIS, 27 DCIS and 12 minimal invasive cancers. There was a significant correlation between p53 expression and c-erbB-2. Both parameters were associated with high proliferation rate and negativity for steroid hormone receptor status. Nuclear pleomorphism could become a comparable prognostic marker in DCIS as it is for infiltrating carcinomas.