Vimentin—a new prognostic parameter in breast carcinoma?

This report describes a positive relationship between vimentin expression in infiltrating ductal breast carcinoma, and high tumour growth fraction. Vimentin expression is potentially a predictor of aggressive behaviour, and such carcinomas may benefit from early adjuvant therapy. Eighty‐four malignant breast neoplasms were stained with monoclonal anti‐vimentin and anti‐cytokeratin antibodies. The tumour growth fractions were determined by immunostaming cryostat sections with the Ki‐67 antibody. Seven (9.2 per cent) of 76 infiltrating ductal carcinomas co‐expressed cytokeratin and vimentin intermediate filaments in more than 50 per cent of neoplastic cells. In each case, the corresponding Ki‐67 count was ≥40 percent, significantly higher than the mean growth fraction for all tumours examined (P<0.0001). Vimentin immunoreactivity was also positively related to the histological grade of the ductal carcinomas (P<0.002) and inversely related to tumour ER count (P<0.0002) and patient age (P<0.01). No relationship was observed between vimentin positivity and either the presence of axillary nodal metastases or primary tumour size.