Cathepsin D in invasive ductal NOS, medullary, lobular and mucinous breast carcinoma. An immunohistochemical study.

Cathepsin D expression was determined by immunohistochemistry in 445 formalin fixed, paraffin embedded primary invasive breast carcinomas. We found: 1. a relationship between cathepsin D expression and histological type of tumour, 2. a negative correlation between cathepsin D expression and histological grade, 3. a negative correlation between cathepsin D expression and tumour diameter, 4. a relationship between the morphology of cathepsin D granules and histological type of the tumour.