[Telomerase activity in benign proliferative breast disease and breast cancer]

The application of telomerase activity is expected to serve as a reliable indicator of biological malignancy in breast tumors. We performed a study to quantify telomerase activity, the results of which revealed that this activity tends to be unexpectedly low in scirrhous carcinoma having low histological differentiation. It is therefore felt that additional studies at the tissue level using in situ hybridization will be required in the future. Although we think that atypical cystic duct is a true pre-cancerous lesion in the sense of having a high possibility of progressing into breast cancer, it will be interesting to determine whether or not the tissue is composed of cells having telomerase activity.