The problem of "chronic mastitis" with epitheliosis.

The incidence of breast cancer complicating chronic mastitis with epitheliosis has been reported to be as high as 45% and as low as 6%. At least part of this discrepancy appears to be due to difficulty in distinguishing between benign and malignant intraduct epithelial proliferation.A small series is presented here in which the incidence of invasive cancer after local excision of breast tissue showing chronic mastitis with epitheliosis was nil. It is concluded that it is necessary to follow up larger series of cases longer before it can be said that severe epitheliosis and borderline lesions should in all cases be treated by anything more radical than local excision.