Vascular infiltration in benign breast disease.

Infiltration of the walls of blood vessels by mammary epithelium was found in two cases of sclerosing adenosis. Survey of a series of cases of sclerosing adenosis and severe epitheliosis revealed a 10 per cent incidence of vascular infiltration. Usually only a single vein was involved but in the propositus an artery and two veins were infiltrated. The findings highlight the infiltrative propensities of sclerosing adenosis, already recognised as infiltrating nerve sheaths. The vascular lesions appear to be benign structurally and this is borne out by the clinical behaviour.