Triple Negative Breast Cancer

Disclaimer:
This blog is for informational purposes only and should not be taken as medical advice. Content is sourced from third parties, and we do not guarantee accuracy or accept any liability for its use. Always consult a qualified healthcare professional for medical guidance.

What is Triple Negative Breast Cancer?

Triple Negative Breast Cancer (TNBC) is an aggressive breast cancer subtype lacking estrogen receptor (ER), progesterone receptor (PR), and HER2 expression, comprising 10-15% of breast cancers, with ~40,000 US cases annually in 2025. It disproportionately affects younger women (<40), Black women, and BRCA1 mutation carriers (20-30% of TNBC). Highly heterogeneous, it has a high recurrence risk and metastatic potential, often to lungs, liver, or brain, but responds to chemotherapy.

Symptoms

Symptoms include a palpable breast lump (often fast-growing), skin changes (dimpling, redness), nipple inversion, discharge (bloody), breast pain, and swollen axillary nodes. Advanced TNBC causes fatigue, weight loss, shortness of breath (lung metastases), or neurological symptoms (brain metastases). Symptoms progress rapidly, often within weeks.

Causes

TNBC is driven by genetic mutations (BRCA1, TP53, PIK3CA), with risk factors including younger age, Black ethnicity, family history, obesity, and nulliparity. BRCA1 mutations increase risk 20-30%. In 2025, tumor microenvironment and immune evasion are key, with no hormonal drivers.

Diagnosis

Diagnosis uses mammography, ultrasound, MRI, and core biopsy with immunohistochemistry (ER/PR/HER2 negative). Molecular subtyping (e.g., basal-like) guides prognosis. Imaging (CT/PET) assesses metastases. In 2025, AI mammography and liquid biopsies improve detection.

Treatment

Surgery (lumpectomy/mastectomy) is standard, with neoadjuvant chemotherapy (anthracyclines, taxanes) shrinking tumors in 50-60%. Immunotherapy (pembrolizumab for PD-L1+) and ADCs (sacituzumab govitecan) achieve 40% response in metastatic TNBC. PARP inhibitors (olaparib) for BRCA mutations. In 2025, TIL therapy shows promise.

Future Outlook

In 2025, 5-year survival is 77% overall, 91% localized, 12% metastatic. Immunotherapy improves metastatic survival to 2-3 years. By 2030, vaccines and CAR-T could achieve 90% early-stage and 30% metastatic survival.

Sources

Cleveland Clinic’s “Triple Negative Breast Cancer: Symptoms, Causes & Treatment”; Mayo Clinic’s “Triple-negative breast cancer – Symptoms and causes”; NCI’s “Triple Negative Breast Cancer Treatment”; Breast Cancer Research Foundation’s “Triple Negative Breast Cancer”; PMC’s “TNBC: Advances in 2025”.