Breast cancer in the elderly: a histological assessment

Abstract

To understand the correlation between the expression status of different biological markers in breast cancers in the elderly. Three hundred and ninety-seven cases were evaluated for expression of hormone receptors [oestrogen receptors (ER) alpha and beta, progesterone receptor (PR)], basal markers [p63, cytokeratin (CK) 5/6 and CK14] and others (HER2/neu, synaptophysin and chromogranin). The expression rates were 60, 29, 25, 6, 14, 8, 28, 17 and 5%, respectively, for these markers. The expression of ER alpha and beta, PR, synaptophysin and chromogranin at any level correlated with low nuclear or tumour grades, whereas the expression of HER2/neu, CK5/6 and CK14 at any level correlated with high nuclear grade. By using hierarchical clustering, groups of HER2, luminal and basal types were identified. In addition, a neuroendocrine group was also identified, being characterized by expression of synaptophysin, chromogranin, ER and PR, but not HER2/neu, and other basal cytokeratins. This group was associated with lower nuclear grade, and hence better prognosis. Breast cancer in the elderly shows similar molecular groupings as other breast cancers, with an additional neuroendocrine group that is associated with a favourable biological marker profile.