Immunohistochemical study of cell cycle regulatory proteins in intraductal breast carcinomas--a preliminary study

The aim of this study was to assess the levels of cell cycle regulatory proteins p21waf1 (p21), p53, Cyclin A, Cyclin D1 and Ki-67 to see whether they correlated with recurrence-free survival (RFS). From 1982 to 1996, 50 patients aged less than 51 years underwent lumpectomy followed by radiotherapy for a pure ductal carcinoma in situ (DCIS). For each case, the following immunohistochemical stains were carried out: Ki-67, Cyclin A, Cyclin D1, p53 and p21waf1 (p21). The percentage of positive nuclei was assessed. Multiple combinations of these factors were performed; in particular, we called the sum of Ki-67 and Cyclin A a global proliferation factor (GPF). Correlations with classical clinicopathological data were assessed. After a multivariate analysis, only GPF, Van Nuys Prognostic Index (VNPI) grade and mitotic index were independent predictive factors of recurrence in the whole population. In the population with close surgical margins, when the GPF level was less than the 25th percentile or more than the 75th percentile recurrence was low. In this preliminary study, GPF seems to be of interest to help in the decision process in the post-surgical management of the patient.