The impact of treatment on the risk of second malignancy after Hodgkin's disease.

editorial The impact of treatment on the risk of second malignancy after Hodgkin's disease In the last several decades, there has been a steady improvement in the cure rate of patients diagnosed with Hodgkin's disease as more effective treatment and more accurate staging techniques become available [1]. With the growing number of patients surviving Hodgkin's disease, various delayed complications are being increasingly recognized. Second malignancy after Hodgkin's disease, first reported in the early 1970s [2], is one of the most serious late effects and is the leading cause of death in long-term survivors of Hodgkin's disease [3, 4]. The elevated risk has largely been attributed to leukemogenic or carcinogenic effects of the treatments for Hodgkin's disease. There are likely other contributing factors, however, including an impaired immune system related to treatments or the disease itself and genetic susceptibility in some of the patients. The identification of risk factors for the development of second malignancy after Hodgkin's disease can be helpful in guiding practice. For patients with risk factors that are modifiable (e.g. tobacco use, sun exposure, dietary habits), counseling and behavioral modification both at the time of Hodgkin's disease diagnosis and during follow-up can serve to lower the risk. Patients with risk factors that cannot be modified (e.g. gender, young age at treatment, family history) can be targeted for more vigilant follow-up and perhaps more intensive cancer screening. Treatment-related risk factors can fall into either of these two categories. They are modifiable in patients with newly diagnosed Hodgkin's disease, and data on the contribution of the various treatment exposures to the risk of second malignancy have motivated clinical investigators to design trials that aim at reducing or eliminating specific treatments. For survivors who have already completed therapy, with known exposure to high-risk treatments, they may be candidates for more rigorous follow-up and screening programs. Understanding treatment-related risk factors for second malignancy risk after Hodgkin's disease is therefore crucial as it can have management implications in both newly diagnosed Hodgkin's disease patients and in survivors of the disease. The majority of studies analyzing second malignancy risk after Hodgkin's disease and the associated risk factors are in the form of retrospective cohort or case–control studies [5–13]. In evaluating second malignancy risk with respect to treatment exposure, the main limitation of a retrospective study design is the varying follow-up time of the different treatments as therapeutic approaches for Hodgkin's disease evolve over time. …