Triple-negative breast cancer: epidemiological considerations and recommendations

Area of Science:

• Oncology
• Epidemiology
• Public Health

Background:

• Breast cancer is a leading global health concern, with increasing incidence but declining mortality in high-income nations.
• Recent advancements have led to new breast cancer classifications with prognostic and therapeutic implications.
• Triple-negative breast cancer (TNBC) lacks estrogen and progesterone receptors and HER2 overexpression, representing 10-20% of invasive cases.

Purpose of the Study:

• To review epidemiological findings on triple-negative breast cancer (TNBC).
• To highlight characteristics and prognosis associated with TNBC.
• To identify research needs for TNBC prevention and understanding.

Main Methods:

• Review of existing epidemiological data and scientific literature on breast cancer subtypes.
• Analysis of clinical and biological characteristics of TNBC.
• Synthesis of findings regarding risk factors, recurrence, and mortality.

Main Results:

• TNBC shows a peak recurrence risk within 3 years and increased mortality for 5 years post-diagnosis.
• TNBC is more prevalent in women of African descent, pre-menopausal women, and is linked to younger age, advanced stage, and BRCA1 mutations.
• TNBC is associated with a poorer prognosis compared to other major breast cancer subtypes.

Conclusions:

• There is an urgent need for more epidemiological studies on breast cancer subtypes, integrating etiological and lifestyle factors.
• Population-based data on the clinical and biological relevance of TNBC from cancer registries is essential.
• Understanding TNBC etiology is critical for developing prevention strategies for non-hormone-dependent breast cancer.