Three-dimensional atypical structure in intraductal carcinoma differentiating from papilloma and papillomatosis of the breast.

The basic architectural pattern of intraductal proliferative lesions of the breast was established by reconstructing serial sections of luminal spaces and interluminal areas of glandular structures. The materials were surgical specimens from twenty patients with intraductal carcinoma, papilloma, papillomatosis, or so-called borderline lesion. In papilloma and papillomatosis, the luminal spaces were tubular and interconnected forming a three-dimensional (3-D) network, whereas carcinoma was a porous structure with dispersed lumina. The latter represented 3-D atypical structure in intraductal carcinoma. In borderline lesion the architecture was an intermediate type, with separate lumina partially transformed into tubular shapes. It was also confirmed that the porous structure of carcinoma observed in 3-D reconstructions corresponded to the cribriform pattern seen in 2-D figures, while the network of papilloma produced a complex glandular pattern. A geometric parameter was devised to measure the different 3-D patterns of lumina and their 2-D expressions. It was concluded that the 3-D architectural pattern of intraductal proliferations was sufficiently characteristic to be of diagnostic value in differentiating these diseases.