Collagen composition in the ductal infiltrating carcinoma of human breast

Ductal infiltrating carcinoma of the breast is characterized by a remarkable amount of collagen fibrils surrounding nests and cords of neoplastic cells. Sequential extractions with pepsin release three classes of intact collagen chains, which have been identified as alpha 1 (I), alpha 2 (I) and alpha 1 (III) types. Alpha 1 (I) is prominent among these classes