QUANTITATIVE HISTOPATHOLOGICAL VARIABLES IN IN-SITU AND INVASIVE DUCTAL AND LOBULAR CARCINOMAS OF THE BREAST

This study was carried out to-compare quantitative histopathological e stimates obtained in normal breast epithelium (N=15), lobular carcinom a in situ (N=29), ductal carcinoma in situ (N=24), invasive lobular ca rcinoma (N=39), and invasive ductal carcinoma (N=71) of the female bre ast. Using unbiased stereology, the three-dimensional mean nuclear siz e, ($) over bar v(v)(nuc), was estimated in routine histological secti ons, along with morphometric point-counting based estimates of the mea n nuclear profile area, ($) over bar alpha(H)(nuc), and estimates of t he nuclear density index, NI, the mitotic index, MT, and the nuclear v olume fraction, V-v(nuc/tis). The ($) over bar v(v)(nuc), ($) over bar alpha(H)(nuc), and MI were, on average, larger in ductal than in lobu lar carcinomas (2p less than or equal to 0.01), whereas the mean NI wa s smaller in ductal carcinomas (2p=3.10(-4)). Comparing estimates obta ined in tumors of pure ductal carcinoma in situ (N=11) with those obta ined in tumors of pure lobular carcinoma in situ (N=7), only the diffe rence in mean NI reached statistical significance (2p=0.001). Several significant differences were found between means of quantitative histo pathological estimates obtained in normal breast epithelium, pure in s itu lesions, and invasive carcinomas. Overlaps were, however, evident among the groups. There were no significant differences between means of the quantitative variables obtained in carcinoma in situ of the duc tal and the lobular type with or without accompanying invasive carcino ma (2p greater than or equal to 0.22). A close correlation was found b etween estimates of ($) over bar v(v)(nuc) obtained in the in situ com ponent and the invasive part of ductal carcinomas (r=0.86, 2p=2.10(-4) ). Previous studies have shown prognostic value of quantitative histop athological variables in breast carcinomas. The present study points t o an additional value of the investigated variables in the diagnostic separation of normal breast epithelium, in situ lesions, and invasive carcinomas. The quantitative variables obtained in the in situ lesions did not indicate whether an accompanying invasive tumor was present o r not.