I read with interest the report by Rodrigues et al.1 on the differences in the molecular features of ductal carcinoma in situ between younger and older women. It appears that the ‘immunotype’ estrogen receptor (ER)−/progesterone receptor (PR)−/HER-2+++ is overrepresented in the younger age group.
This is the pattern that I have long associated with apocrine carcinoma, whether infiltrating or in situ. Infiltrating apocrine carcinoma has been associated with poor prognosis and, in my anecdotal experience, a higher rate of pleura-involving lung metastases and a higher rate of inflammatory breast carcinoma compared with other types of breast carcinoma. I also have noted the link between the infiltrating and in situ forms of apocrine carcinoma, whether synchronous or metachronous. I would like to ask the authors whether they observed this histologic finding (apocrine appearance) in the group that they identified as strongly HER-2/neu-positive and ER- and PR-negative.
An intriguing aspect of apocrine carcinoma (infiltrating or in situ) is the efficacy of antiandrogen therapy in treating it. I am unaware of any study examining age correlations, hormone responsiveness, or menopausal status, but exploration of all of these factors would be worth pursuing.