Female survivors of childhood Hodgkin lymphoma (HL) who received chest radiation can reduce their risk of breast cancer through early screening, according to a recent study published in the Journal of the National Cancer Institute. Thoracic radiation therapy during childhood cancer increases the risk of breast cancer.1
In this study, researchers developed a mathematical model to assess the effectiveness of early screening (start screening at 25 years) vs later screening (start screening at 40 years). In both screening model groups, thoracic radiation was applied at age 15 years. Sensitivity analyses determined robustness of the model over a range of conditions.
According to the model, an estimated 80 HL survivors would need to be screened via MRI to prevent 1 death. The sensitivity analyses estimated 71 to 333 survivors would need an MRI-based screen to prevent 1 death.
The absolute risk of breast cancer mortality by age 75 years with no early screening was 16.65%. Annual mammography reduced this risk to 16.28%, annual MRI to 15.40%, same-day annual mammography and MRI to 15.38%, and alternating mammography and MRI every 6 months to 15.37%. MRI combined with mammography produced 99.52 false positives per 1000 screenings done between ages 25 and 39 years.
These results indicate early, MRI-based screening could best reduce breast cancer mortality in survivors of childhood HL and might be merited even with MRI’s tendency to produce substantial false-positive results.
“If you are a young woman who was treated with radiation therapy to your chest as a teenager or child for HL, or for that matter chest radiation therapy for any reason, you should be having a conversation with your family doctor or your oncologist about whether to start breast cancer screening earlier than most women would,” said David Hodgson, MD, MPH, FRCPC, a radiation oncologist at the Princess Margaret Cancer Centre, University Health Network and associate professor in the Department of Radiation Oncology, the University of Toronto, in Toronto, Canada, and lead author on the study.
The Canadian Cancer Society, the Pediatric Oncology Group of Ontario, a Research Chair from Cancer Care Ontario, and The Princess Margaret Cancer Foundation funded this research.
1. Hodgson DC, Cotton C, Crystal P, Nathan PC. Impact of early breast cancer screening on mortality among young survivors of childhood Hodgkin’s lymphoma. J Natl Cancer Inst. doi:10.1093/jnci/djw010.