{"entity":{"id":"apocrine-carcinoma-breast","kind":"cancer","name":"Apocrine carcinoma of the breast","aka":["Carcinoma with apocrine differentiation","Apocrine breast cancer","Molecular apocrine carcinoma (overlapping expression subtype)"],"tldr":"Apocrine breast cancers are made of large cells resembling sweat-gland cells. They lack oestrogen and progesterone receptors but carry the androgen receptor, so the triple-negative ones sit in the luminal androgen receptor group and are the tumours in which androgen-blocking drugs have been tried.","summary":"Apocrine carcinoma shows distinct morphology (abundant eosinophilic granular cytoplasm and prominent nucleoli) with a characteristic steroid receptor profile that is oestrogen and progesterone receptor negative and androgen receptor positive; strictly defined, apocrine carcinomas express either HER2 or EGFR, which with androgen receptor positivity makes them candidates for targeted therapies (Vranic 2013). In the 5th edition of the WHO classification the entity is discussed as carcinoma with apocrine differentiation, reflecting debate about how much apocrine morphology is needed (Cserni 2020). The transcriptionally defined molecular apocrine group, ESR1-negative and AR- and FOXA1-positive, was 67 percent HER2 3+ and 57 percent GCDFP15-positive by immunohistochemistry and clinically aggressive, and almost all (94 percent) carried the HER2 3+ or GCDFP15-positive signature that none of the basal-like controls did (Lehmann-Che 2013). The HER2-negative apocrine tumours are therefore the histological face of the luminal androgen receptor subtype, whose phase 2 trials of bicalutamide and enzalutamide are on that page; the HER2-positive ones are treated as HER2-positive breast cancer.","asOf":"2026-09-24","wikipedia":"https://en.wikipedia.org/wiki/Breast_cancer_classification","links":[{"label":"Vranic, Histol Histopathol 2013: apocrine carcinoma of the breast, a comprehensive review","url":"https://doi.org/10.14670/hh-28.1393"},{"label":"Lehmann-Che, Breast Cancer Res 2013: molecular apocrine breast cancers overexpress HER2 or GCDFP15","url":"https://doi.org/10.1186/bcr3421"},{"label":"Cserni, Pathologica 2020: histological type and typing of breast carcinomas and WHO classification changes","url":"https://doi.org/10.32074/1591-951x-1-20"},{"label":"Thomas, NPJ Breast Cancer 2023: rare subtypes of triple-negative breast cancer","url":"https://doi.org/10.1038/s41523-023-00554-x"}],"tags":["breast","tnbc","subtype-page"],"related":["tnbc","tnbc-luminal-androgen-receptor","breast-her2-positive"],"cancers":[],"sections":[],"technologies":[],"targets":["androgen-receptor","her2","egfr"],"drugs":["bicalutamide","enzalutamide"],"companies":[],"institutions":[],"pathways":[],"terms":["androgen-receptor-positive-tnbc"],"trials":[],"people":[],"bottlenecks":[],"keyPapers":[],"journals":[],"dependsOn":[],"notes":[],"group":"breast","burden":"A rare special type; the WHO classification counts carcinomas with apocrine differentiation among the special types and the molecular apocrine expression group overlaps the luminal androgen receptor subtype (Cserni 2020; Lehmann-Che 2013).","subtypes":["HER2-negative apocrine carcinoma (triple-negative, luminal androgen receptor subtype)","HER2-positive apocrine carcinoma (treated as HER2-positive breast cancer)","Invasive carcinoma of no special type (ductal) with apocrine differentiation"],"biomarkers":["ER and PR negative with androgen receptor positive","HER2 status (3+ in two thirds of molecular apocrine tumours)","GCDFP15 (gross cystic disease fluid protein 15) and FOXA1 expression"],"standardOfCare":[{"setting":"Triple-negative apocrine carcinoma","approach":"As for triple-negative disease of no special type; androgen receptor antagonists only within trials (clinical benefit rates 19 to 33 percent in phase 2).","refs":["bicalutamide","enzalutamide","androgen-receptor"]}],"stateOfArt":[],"history":[],"pipeline":[],"openProblems":[],"parent":"tnbc"},"route":"/cancers/apocrine-carcinoma-breast/","neighbours":{"cancer":[{"id":"breast-her2-positive","kind":"cancer","name":"HER2-positive breast cancer","route":"/cancers/breast-her2-positive/"},{"id":"tnbc-luminal-androgen-receptor","kind":"cancer","name":"Luminal androgen receptor triple-negative breast cancer (LAR)","route":"/cancers/tnbc-luminal-androgen-receptor/"},{"id":"tnbc","kind":"cancer","name":"Triple-negative breast cancer (TNBC)","route":"/cancers/tnbc/"}],"target":[{"id":"androgen-receptor","kind":"target","name":"Androgen receptor","route":"/targets/androgen-receptor/"},{"id":"egfr","kind":"target","name":"EGFR","route":"/targets/egfr/"},{"id":"her2","kind":"target","name":"HER2","route":"/targets/her2/"}],"drug":[{"id":"bicalutamide","kind":"drug","name":"Bicalutamide","route":"/drugs/bicalutamide/"},{"id":"enzalutamide","kind":"drug","name":"Enzalutamide","route":"/drugs/enzalutamide/"}],"term":[{"id":"androgen-receptor-positive-tnbc","kind":"term","name":"Androgen receptor-positive triple-negative breast cancer","route":"/terms/androgen-receptor-positive-tnbc/"},{"id":"luminal-androgen-receptor","kind":"term","name":"Luminal androgen receptor (LAR) subtype","route":"/terms/luminal-androgen-receptor/"}]}}