NCI reports that researchers have developed a model for estimating a woman's risk of developing
breast cancer after being treated with large-field chest radiotherapy for Hodgkin's lymphoma (HL). Using the model, they determined that the cumulative absolute risk of breast cancer among female HL survivors increases with age at the end of follow-up, time since diagnosis, and radiation dose.
Breast cancer is the most common solid tumor among young women who survive HL, but individualized risk projections of cumulative absolute risk had not previously been developed. Projections could be used to counsel HL survivors and plan long-term management and prevention strategies.
To create the model, a team led by Drs. Lois B. Travis and Mitchell H. Gail of NCI analyzed data from an international population-based, case-control study of nearly 3,800 female HL survivors who were diagnosed at age 30 or younger. Among the survivors, 105 developed breast cancer, according to findings in the October 5 Journal of the National Cancer Institute.
Because the study included women diagnosed from 1965 through 1994, the model is most appropriate for survivors who received HL treatments commonly used in the past. The researchers urge caution in applying the findings to women treated with newer therapies, such as limited-field radiotherapy or ovary-sparing chemotherapy.
Gains in long-term survival provided by radiation therapy and chemotherapy should always be balanced against the associated risks of secondary cancers and other late sequelae, the researchers note. The risk projections will "serve as a unique and valuable resource for the large number of current HL survivors given therapeutic regimens of the past," they write.
