Second Primary Gastrointestinal Cancers
DCEG investigators are leading a multi-center international study of second primary gastrointestinal (GI) cancers among survivors of Hodgkin lymphoma and cancers of the testis, breast, and cervix. This is the first study to comprehensively investigate the radiation dose-response for upper GI cancers following fractionated, higher dose radiation exposures. It is also one of the few studies to investigate the risk of secondary, non-hematologic malignancies following treatment with chemotherapy. The primary aim of the study is to provide new information on the relation between radiation dose and cancer risk for three GI organs (stomach, esophagus, and pancreas), for which few quantitative data exist.
Four international population-based cohorts including over 900,000 1-year survivors of Hodgkin lymphoma and cancers of the testis, breast, and cervix were assembled. Analyses of these cohorts have newly quantified the age and temporal patterns of risk for subsequent cancer and non-cancer outcomes, and highlighted that many of the excess risks often persist for over 25 years following the first cancer diagnosis.
- Survivors of testicular cancer were demonstrated to have increased risk of mortality from infections, digestive diseases, and circulatory diseases when compared with the general population;
- Survivors of both breast and cervical cancer experienced excess risks of subsequent cancer at least 25 years after diagnosis, particularly for women diagnosed at young ages;
- In addition, breast cancer survivors had a higher risk of suicide than women in the general population;
- Risk of solid cancers following Hodgkin lymphoma was strongly related to both young age at diagnosis and attained age, but did not appear to have changed over calendar time. In contrast, risk of acute myeloid leukemia following Hodgkin lymphoma decreased over time, likely due to changes in chemotherapy.
Given the extensive nature of data collection required for a detailed evaluation of dose response relations for radiotherapy and chemotherapy, a nested-case control design was chosen to address this aim, resulting in a total of seven case-control studies. Analyses have demonstrated linear increase in risk associated with increasing radiation dose for stomach, pancreas, and esophagus cancers after Hodgkin lymphoma; stomach and pancreas cancers after testis cancer; esophagus cancer after breast cancer; and stomach cancer after cervical cancer.
For more information, contact Lindsay Morton.