Mammographically-detected ductal in situ carcinoma of the breast analyzed with a new classification. A study of 127 cases: correlation with estrogen and progesterone receptors, p53 and c-erbB-2 proteins, and proliferative activity.

The new histologic classification proposed by Holland et al was applied to 127 cases of mammographically-detected ductal carcinoma in situ (DCIS). The relationship between histologic types and tumor cell expression of estrogen and progesterone receptors, p53 protein, c-erbB-2 oncoprotein, and proliferative activity markers was evaluated. There were 38 (30%) well differentiated, 39 (31%) intermediately differentiated and 50 (39%) poorly differentiated DCIS. Immunohistochemistry showed that 81% of the tumors were estrogen-receptor positive and 73% progesterone receptor positive. p53 protein and c-erbB-2 oncoprotein expression was identified in 40% and 57% of the cases, respectively. Growth-fraction determination with the Ki-67 antibody showed that 52% of the tumors had high proliferative activity. A highly significant association was found between the histologic types of DCIS and p53 protein, c-erB-b2 oncoprotein, and proliferative activity marker expression: these biological markers were more frequently overexpressed in less differentiated DCIS. No significant relationship with estrogen or progesterone receptor expression was noted. A strong relationship with the amount of tumor necrosis was also found. The clinical significance of these results should, however, be determined by long-term follow-up studies of patients with DCIS.