Associação entre a presença da proteína p53 e o grau de diferenciação em carcinomas ductais invasivos de mama

Abstract

PURPOSE: to assess p53 protein expression in infiltrating ductal breast carcinoma and to analyze its association with histological and nuclear grade. METHODS: sixty-five consecutive females who were diagnosed with primary infiltrating ductal breast tumor from July 1999 to July 2001 were included in the present study. Mean patient age at diagnosis was 69.2 years (range 41 - 90). All patients were first treated with surgical therapy, conservative surgery or mastectomy. None of the patients received any preoperative adjuvant therapy. Resected breast tumor specimens were fixed in 10% formalin, paraffin embedded, and conserved for immunohistochemical analysis. p53 protein expression was evaluated. Primary monoclonal anti-human p53 antibody DO-7 (DAKO) was used. Frequency distributions were tested by the c2 test. A level of p<0,05 was considered significant. RESULTS: p53 expression was detected in 24 (36,9%) of 65 carcinomas. Of the cases with protein expression, 13 (54,2%) were high or histological grade III, 8 (33,3%), were grade II, 3 (12,5%) were grade I. On nuclear grade analysis, of the cases with protein expression, 13 (4,2%) were nuclear grade III, 9 (37,5%) were grade II and 2 (8,3%) were grade I. p53 expression was frequent in carcinomas with high histological and nuclear grades. CONCLUSIONS: p53 expression was significantly associated with the histological grade. On the other hand, nuclear grade was not significantly related to p53 expression.