CORRELATION BETWEEN P53 MUTATIONS AND ANTIBODY STAINING IN BREAST-CARCINOMA

Abnormalities of the p53 gene and protein were examined in 81 primary breast carcinoma samples. Using a polymerase chain reaction-single-str and conformational polymorphism (PCR-SSCP) analysis, mutations in p53 exons 5-8 were identified in 13 of 81 tumours (16 per cent) and confir med by DNA sequencing. Positive staining for p53 protein was detected in ten of 77 (13 per cent) of these tumours using polyclonal CMI antib ody on formalin-fixed tissue. Mutations detected by PCR-SSCP analysis were more common in grade III tumours (P = 0.015), but no correlation was found with tumour size, node status or level of epidermal growth f actor receptor expression. A p53 mutation was associated with positive antibody staining in only two patients. Positive immunohistochemical staining using a p53 antibody may detect p53 protein expression, but t his may not correlate directly with an underlying mutation in the hot spot region examined.