PREOPERATIVE DETECTION OF C-ERBB-2 GENE AMPLIFICATION AS A PREDICTOR OF LOCAL RECURRENCE AFTER CONSERVATIVE TREATMENT FOR BREAST-CARCINOMA

The presence of comedo carcinoma in the intraductal component is an im portant pathologic feature for predicting local recurrence after breas t conserving treatment. Furthermore, the c-erbB-2 gene is frequently o verexpressed in comedo carcinoma and it correlates well with gene ampl ification. This study revealed that 77.0% of the c-erbB-2 amplificatio n positive tumors had intraductal lesions of the comedo type; while on ly 6.7% of the amplification negative tumors had comedo carcinoma (X(2 )=106.6, p<0.0001). Accordingly, when c-erbB-2 amplification is detect ed in the invasive tumor, intraductal lesions which may co-exist in th e tumor are likely to be comedo carcinoma. To predict the presence of comedo type intraductal carcinoma, c-erbB-2 gene amplification was ana lysed by means of polymerase chain reaction (PCR) from small samples o f fine-needle aspiration biopsies. Breast tumors from ten patients wer e analysed and one had a 3.4-fold amplification of c-erbB-2 gene. The pathological appearance of this case was pure ductal carcinoma in situ with comedo carcinoma. The preoperative detection of c-erbB-2 gene am plification by PCR will be a useful means of selecting patients at hig h risk for local recurrence after breast conserving treatment.