# What is Triple-negative breast cancer (TNBC)?

Source: https://oncologyistanbul.com/glossary/triple-negative-breast-cancer

> A breast cancer subtype that tests negative for estrogen receptor, progesterone receptor, and HER2 — meaning hormone and HER2-targeted therapies don't apply.

Because triple-negative tumors lack all three common targets, treatment relies more heavily on chemotherapy (often given neoadjuvantly) and, increasingly, immunotherapy in specific situations. It tends to be more aggressive on average, which is why the tumor board often recommends treatment before surgery for this subtype.

## Related
- [Breast cancer treatment](https://oncologyistanbul.com/cancers/breast)

## Authoritative references
- [Wikipedia](https://en.wikipedia.org/wiki/Triple-negative_breast_cancer)
- [Wikidata](https://www.wikidata.org/wiki/Q7843332)

Full glossary: https://oncologyistanbul.com/glossary