Biophenotypes of breast carcinoma in situ defined by image analysis of biological parameters.

In 50 in situ breast cancers an immunohistochemical study, evaluating estrogen (ER) and progesterone (PR) receptors, Proliferation Index (PI), c-erbB-2/Neu and p53 expression was performed. According to histopathological diagnosis, cases were classified as follows: 14 comedo, 8 solid, 5 micropapillary, 6 lobular, 3 papillary, 1 apocrine and 12 mixed in situ carcinomas. The quantitation of immunohistochemical results was obtained with an image analysis computerized system (CAS 200) with a lesion-field method; tumors were subdivided in fields (1177) histologically homogeneous, with 40 x microscopic objective. For ER, PR, Neu and p53, 10% of the positive area was used as cut-off value; 13% was used for PI. Cribriform and lobular types showed a higher positivity for ER (92.1% and 95.5% of the fields); cribriform and papillary a higher for PR (92.6% and 93.9%). Comedo variant demonstrated the higher PI (52.7%), Neu and p53 expression (67.7% and 43%). A cluster analysis performed on 608 fields, defined two groups according to biological homogeneous criteria. The results obtained identify the different biophenotypes of in situ carcinomas, suggesting the possibility of multiple cancerogenetic ways with a different weight of biological events.