Breast Cancer After Supradiaphragmatic Irradiation for Hodgkin's Disease; Risk Analysis and Possible Surveillance Strategies
Hodgkin’s disease is one of the first cancers that was found to be curable with radiation therapy. Since that time, reports have shown that long-term survivors are at an increased risk of treatment toxicities and secondary cancers, with the highest risk seen in women. Secondary cancers generally present 5 to 10 years after radiation therapy and/or chemotherapy. This study was done to look at the risk of breast cancer following chest irradiation for Hodgkin’s Disease, and to recommend appropriate surveillance for survivors.
Medical records of 249 women under the age of 60 (ages 6-59 years) were reviewed. Thirty-six patients developed breast cancer, 11 with disease in both breasts. The median * time from radiation to breast cancer diagnosis was 18.4 years, with the earliest being 6.4 years after treatment. The risk was highest 15 years or more after treatment. Age at the time of treatment was a factor as well, with risk being far higher for women treated with radiation before age 20 and then tapering with increasing age. Cases of breast cancer were detected via mammography (55.6%), self-examination (25.9%), pathologic evaluation following elective mastectomy (11.1%), and clinical examination (7.4%). Interestingly, no association was seen between the development of breast cancer and the dose and method of radiation or use of chemotherapy.
Beginning 10 years after chest radiation for Hodgkin’s disease, intensive screening (breast MRI, mammogram), discussion, chemoprevention, and/or prophylactic mastectomy should be performed.
* The median is the "middle of the pack", where half of the patients have had more years since treatment and half have less. For instance, if the patients were 2, 4, 6, 10.8, 12, 12 and 14 years since treatment, 10.8 is the mid point, or the median. It is different from the mean, which would be the average time since treatment.
Partially funded by an unrestricted educational grant from Bristol-Myers Squibb.