Therapeutic Radiation for Lymphoma and Risk of Second Primary Malignant Mesothelioma

Four Exponent scientists in the Center for Health Sciences, Ellen Chang, Edmund Lau, Fionna Mowat, and Jane Teta, have published a new article entitled, "Therapeutic Radiation for Lymphoma and Risk of Second Primary Malignant Lymphoma" in the journal Cancer Causes & Control. The article describes a study of nearly 50,000 Hodgkin lymphoma patients and over 250,000 non-Hodgkin lymphoma patients across the United States who were followed for up to 41 years after lymphoma diagnosis, from 1973 through 2014, for the occurrence of second primary malignant mesothelioma, a rare cancer of the thin layer of tissue that lines certain parts of the body, including the chest and abdomen.

Using population-based Surveillance, Epidemiology, and End Results data from 18 U.S. cancer registries, the authors found that risk of mesothelioma is increased by over 60% (multivariate adjusted relative risk = 1.64, 95% confidence interval = 1.05 to 2.57) among lymphoma patients who were treated with radiotherapy, compared with those who were not. Radiation-associated risk of mesothelioma was especially increased among lymphoma patients diagnosed before 1995, when radiotherapy doses were higher, and after at least 10 years since lymphoma diagnosis. Radiation-associated risk also appeared to be higher among patients who were younger when diagnosed with lymphoma.

This study, the largest investigation to date of the risk of mesothelioma after radiotherapy for lymphoma, offers greater insight into how radiotherapy-induced mesothelioma varies by patient demographic and disease characteristics, including age, era of diagnosis, and latency. The findings thus augments our understanding of non-asbestos-related causes of this rare and lethal cancer.

Read the full article here.