Background: Young women with neurofibromatosis type 1 (NF1) are reported to have a higher risk of breast cancer than others, and this might have implications for screening programmes. Our aim was to calculate this risk.
Methods: An all-England linked data set of hospital admissions and deaths was analysed to determine age-specific rates of breast cancer in women with NF1 and controls.
Results: The age-specific excess risk of breast cancer, comparing the NF1 cohort with the control cohort, was elevated 6.5-fold (95% confidence interval 2.6-13.5) in women aged 30-39 years. There was a 4.4 (2.5-7.0) times higher risk among women aged 40-49.
Conclusions: Women with NF1 develop breast cancer at younger ages than the general population.