Risks and protective factors for triple negative breast cancer with a focus on micronutrients and infections

Triple negative breast cancer (TNBC) is an aggressive form of breast cancer (BC) with a poor prognosis. Second, patients cannot benefit from targeted therapy, except for those with BRCA1/2 mutations, for whom poly (ADP-ribose) polymerase (PARP) inhibition therapy using olaparib has recently been approved. As global priorities continue to be epidemiological analysis of BC risk factors and early diagnosis, this review focuses on the risks and protective factors associated with TNBC. A PubMed keyword search for new knowledge on the risks and protective factors for TNBC was carried out. We also found statistical information from current online databases concerning the estimated incidence, prevalence and mortality worldwide of this cancer. Traditional risk factors for BC and TNBC are those related to reproduction such as the age of menarche, age of first birth, parity, breastfeeding and age at menopause. Attention needs to be paid to familial BC, weight control, alcohol consumption and regular physical activity. Epidemiological studies on TNBC provide evidence for protective factors such as regular consumption of soya, seafood, green tea, folic acid and vitamin D. Potential risk factors may include night work and viral infectious agents like human papillomavirus (HPV) and Epstein-Barr virus (EBV). Droplet digital methylation-specific PCR (ddMSP) is a possible new screening method for detection of BC including TNBC. Further research is necessary to validate these new factors.