Breast skin thickness: normal range and causes of thickening shown on film-screen mammography

We measured breast skin thickness on the film-screen mammograms of 250 asymptomatic women and found a normal range of 0.7-2.3 mm in the superior quadrant and 0.7-2.7 mm in the inferior quadrant as measured on the mediolateral view and 0.6-2.4 mm in the medial quadrant and 0.5-2.1 mm in the lateral quadrant as measured on the craniocaudad view. In our experience a skin thickness of greater than 2.5 mm suggests the presence of disease. Causes of skin thickening in our series of 44 patients included carcinoma, metastases, post radiation therapy, post surgery, infection, and anasarca. Other reported causes are trauma, fat necrosis, dermatologic conditions, and lymphoma.