Re: Exposure to diagnostic radiation and risk of breast cancer among carriers of BRCA1/2 mutations: retrospective cohort study (GENE-RAD-RISK)
Radiation from mammography increases the risk of breast cancer in susceptible women.1 However, screening has been mostly carried out in the 50 to 69 age groups who are most likely to be taking HRT and who have also had most increases in breast cancer. Please see the England and Wales breast cancer incidence graphs from 1962 to 1999 attached below.
It is important to recognise that increases and reductions in hormone use can either increase or reduce breast cancer registrations and mortality. The carcinogenic effect of progestogens has been underestimated for decades. The combined effects of progestogen use from an early age, plus repeated exposure to radiation from mammography, is even harder to clarify. Reductions in mortality are claimed.2,3
Dr Ann Johnson is concerned that carcinoma in situ is often discovered by screening can lead to overdiagnosis and overtreatment. Carcinoma-in-situ is not usually life threatening in contrast to most malignant tumours which can grow rapidly.4 Dr Johnson thinks that screening has raised the standards of diagnosis and management, but, by removing more slowly growing tumours, it has become harder to elucidate the significance of changes in survival rates.
Also some simple breast tumours regress as soon as hormone use is stopped in my experience. One of the simplest ways to reduce excessive use of screening radiation and increases in breast cancer mortality is to avoid the use of hormones, especially progestogens.5
1 Pijpe A, Andrieu N, Easton D et al. Exposure to diagnostic radiation and risk of breast cancer among carriers of BRCA1/2 mutations: retrospective cohort study (GENE-RAD-RISK). BMJ2012;345:e5660
2 Hawkes N. Lives saved by breast screening outnumber cases of overdiagnosis, review says :BMJ2012;345:e6155
3 Euroscreen Working Group. Summary of the evidence of breast cancer screening outcomes in Europe and first estimate of the benefit and harm balance sheet. J Med Screening 2012;19:suppl 1.
4 Johnson A. ‘Overdiagnosis’ and mortality in breast cancer screening. JR Soc Med 2012:105:317-319
5. Grant ECG. Reductions in hormone use and breast cancer mortality. BMJ;2011: 7 September Rapid Reposnse to Autier P, Boniol M, Gavin A, Vatten L.J. Breast cancer mortality in neighbouring European countries with different levels of screening but similar access to treatment: trend analysis of WHO mortality database. BMJ2011;343:d4411
Competing interests: No competing interests