CD31 PECAM AUTOMATED AND QUANTITATIVE IMMUNOCYTOCHEMICAL ASSAYS IN BREAST CARCINOMAS - CORRELATION WITH PATIENT FOLLOW-UP/

The purpose of this study was to determine the prognostic significance of quantitative CD31 immunohistochemical assays. CD31 assays were per formed on a series of 167 breast carcinoma specimens under optimal tec hnical conditions that involved frozen sections, an automated immunope roxidase technique, and computer-assisted analysis of digitized colore d microscopic images. Results of automated quantitative immunohistoche mical assays were correlated with patient follow-up (9.6 years). Patie nts were divided into two subgroups: those who had axillary lymph node -positive (N+) disease and those who had lymph node-negative (N-) dise ase. The marked immunocytochemical expression of CD31 in tumors (cutof f point, 20%) was significantly (P = .033) associated with a poor over all survival rate (Kaplan-Meier, log rank test); however, a significan t association was not observed in the N+ and N- subgroups. CD31-immuno stained tumor cell surfaces larger than 20% correlated with the metast asis-free survival rate (P = .004) in air patients and in the N+ subgr oup (P = .005) but not in the N- subgroup. In addition, marked immunoc ytochemical expression of CD31 correlated with the short-term disease- free survival rate (P = .04) in the N+ subgroup but not in the N- subg roup. in multivariate analysis (proportional hazards regression Cox mo del) the prognostic significance of CD31 was independent of tumor size and histologic type but not of grade. The results suggest that, under optimal technical conditions (automated and quantitative immunohistoc hemical assays on frozen sections), immunohistochemical expression of CD31 is a significant prognostic indicator of overall and metastasis-f ree survival rates. CD31 has limited prognostic value, however, and is not a completely independent prognostic indicator because it is relat ed to nodal status.