Breastfeeding Associated with Lower Breast Cancer Risk in Women with Li-Fraumeni Syndrome
, by DCEG Staff
In the first study to evaluate reproductive factors and breast cancer risk in women with Li Fraumeni syndrome (LFS), investigators report breastfeeding for at least seven months to be associated with 43 percent reduced breast cancer risk. These findings were published June 15, 2019, in the European Journal of Cancer.
Individuals with LFS experience extremely high risk of cancer over their lifetime. In women, early onset breast cancer is the most common, with a median age at diagnosis of 32 years and an almost 50% cancer risk by age 60. Reproductive factors are known to influence breast cancer risk among women in the general population and in women with other inherited cancer predisposition syndromes, such as those with germline pathogenic BRCA1/2 variants. To determine the role of reproductive factors in this special population, Payal Khincha, M.B.B.S., M.S.H.S., and colleagues, analyzed questionnaire data from 152 women enrolled in the NCI LFS study with confirmed germline TP53 variants; 85 had a breast cancer diagnosis. They found no association of breast cancer risk with earlier age at menarche, ever/never oral contraceptive use, or with whether or not the women had given birth. In the general population, long-duration of breastfeeding (48 months) is associated with reduced breast cancer risk. Among women with LFS, those who breastfed for seven months or more were 43% less likely to develop breast cancer over the study period. The data also suggest that women with LFS who give birth after the age of 30 years may have a slightly increased risk of breast cancer..
These results are an important contribution to the conversation between clinicians, genetic counselors, and patients about the medical benefits of breastfeeding in the context of cancer screening and prevention in women with LFS.
Khincha P et al. Reproductive factors associated with breast cancer risk in Li–Fraumeni syndrome. European Journal of Cancer. June 15, 2019. DOI: 10.1016/j.ejca.2019.05.005. [Epub before print].