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4 slides generated from the cancer page, with a quiz from the open benchmark and speaker notes that cite the sources. Arrow keys move between slides; Print gives one slide per page.
Adenoid cystic carcinoma of the breast is a very rare breast cancer that is triple-negative on testing but behaves almost the opposite of usual triple-negative disease: it seldom reaches the lymph nodes, and nearly everyone is alive at ten years. It is the same tumour type as adenoid cystic carcinoma of the salivary glands and shares its gene fusion.
Adenoid cystic carcinoma of the breast is a special type of basal-like carcinoma with a cribriform, tubular or solid pattern of epithelial and myoepithelial cells. In SEER (1977 to 2006) 338 women were diagnosed, an incidence of 0.92 per million person-years, constant over 30 years; 95 percent presented with localised disease, the highest rates were in ER- and PR-negative tumours, age-specific rates rose until midlife and plateaued as for other ER-negative tumours, and relative survival was 98.1 percent at five years, 94.9 percent at ten and 91.4 percent at fifteen, with no excess of other cancers before or after (Ghabach 2010). The t(6;9) translocation fusing MYB to NFIB is a hallmark of adenoid cystic carcinoma of both breast and head and neck, deleting the microRNA target sites that normally repress MYB (Persson 2009). The European Working Group for Breast Screening Pathology lists classical adenoid cystic carcinoma first among the triple-negative special types with indolent behaviour whose patients are unlikely to benefit from chemotherapy, while noting that the solid-basaloid variant behaves more aggressively (Cserni 2021; Thomas 2023). Its 15-year survival above 90 percent is the clearest illustration that triple-negative is a laboratory category, not a prognosis.
| Setting | Approach | Guideline |
|---|---|---|
| Localised disease | Surgery with clear margins, radiotherapy after breast conservation, and no chemotherapy for the classical type in the European working group consensus; the solid-basaloid variant is managed as high-grade triple-negative disease. | not mapped |