Chest Radiation to Childhood Cancer Patients Ups Risk of Breast Cancer

Children with cancer who receive radiation to the chest, particularly those treated with whole-lung irradiation and high doses of radiation, have a significantly increased risk of developing breast cancer later in life. Furthermore, “mortality associated with breast cancer after childhood cancer is substantial.” These results were recently published in the Journal of Clinical Oncology.

Many children with cancer are treated with radiation to the area of the chest, particularly as prevalent lymph nodes reside in the chest area. However, research has recently unveiled associations between subsequent health issues related with radiation to the chest. Therefore, researchers continue to evaluate data to determine exactly which healthcare issues may occur because of chest radiation so that screening and preventive measures may be put in place.

In addition, radiologists have since fine-tuned their radiation applications based on the risks of secondary health issues.

Researchers from the Memorial-Sloan Kettering Cancer Center in New York recently evaluated data gathered from the Childhood Cancer Survivors Study (CCSS) to determine if variations of chest radiation changed the risk of childhood cancer survivors developing breast cancer. The study included 1,230 female childhood cancer survivors, all of whom received radiation to the chest as a child.

Patients who had radiation delivered to a large-volume of the chest (whole-lung field) had a significantly increased risk of developing breast cancer, regardless of the dose of radiation.
Patients with high doses of radiation therapy delivered to the mantle field (lymph nodes above the diaphragm delivered to the breast bone, under the arms, neck and chest area) also experienced a high risk of developing breast cancer.
Breast cancer was diagnosed in 30% of patients by the age of 50 and 35% of Hodgkin lymphoma survivors.
Mortality from breast cancer at 5 and 10 years following a diagnosis of breast cancer was 10% and 19%, respectively.
Although the fact that breast cancer incidence is significantly increased among childhood cancer survivors who have received chest radiation has been well established, the results from this study help to identify specifically which radiation practices are associated with the increase, allowing for modifications in therapy.

Childhood cancer survivors who receive radiation to the chest, particularly those who received a large volume of radiation or high-doses of radiation, have a significantly increased risk of developing breast cancer by the age of 50. Importantly, mortality from breast cancer among these patients is higher than among the normal population. Survivors of childhood cancer who received radiation to the chest should speak with their healthcare provider regarding appropriate screening measures for breast cancer.

Reference: Moskowitz C, Chou J, Wolden S, et al. Breast cancer after chest radiation therapy for childhood cancer. Journal of Clinical; 23(21):2217-2223.