Since 1971, the number of cancer survivors in the US has tripled. However, with the achievements in patient survival have come second malignancies and cardiovascular disease among survivors, according to a report by a national scientific committee convened by the National Council on Radiation Protection and Measurements.
The Journal of the National Cancer Institute recently published a detailed summary online of the study chaired by Lois B. Travis, MD, ScD, of the University of Rochester Medical Center (URMC). The comprehensive, 425-page report, available in hard copy in the spring, considers some of the most important implications of radiation treatments and includes several significant conclusions and recommendations.
“For many survivors the successes of treatment have been offset by the late effects of cancer and its therapy,” said Travis, a professor in the Department of Radiation Oncology and director of the Rubin Center for Cancer Survivorship at the James P. Wilmot Cancer Center at URMC. “Although many complex factors influence the risk of second malignancies and other health issues after cancer treatment – including lifestyle choices such as diet, exercise, alcohol and tobacco use, as well as genetics, age, and immune system function – it is vital that we develop the best possible long-term risk estimates and prediction models, and that we establish research priorities and identify concrete ways to prevent serious additional health problems among cancer survivors.”
As a cornerstone of cancer treatment, radiation therapy is used in approximately 50% of all cancer cases. Therefore, the consequences of radiation therapy were the committee’s focus. (Chemotherapy, when it is used in combination with radiation, is addressed in the report.)
Key study findings include:
- Newer radiotherapy treatment methods result in a different radiation distribution to organs and tissue compared with older treatment regimens. However, current risk assessment models for second malignancies and cardiovascular disease are often based on older treatment regimens. Newer risk-prediction models should be based on the dose absorbed by the organ and the type of radiation prescribed
- Few studies have gone on to describe survival after the diagnosis of second malignancies
- All aspects of the relationship between radiation dose and risk of second malignancies and heart disease need to be studied
- Long-term, large-scale studies are needed to follow cancer survivors of all ages, but particularly those who are adolescents and young adults, and characterize their risks as they age
- An important noncancer cause of death for some survivors is radiation-related heart disease, including pericardial disease, coronary artery disease, valvular dysfunction, conduction abnormalities, and stroke. To predict the high complication rates in certain populations of cancer patients, more research is needed