Estimation of Mediastinal Toxicities after Radiotherapy for Hodgkin Lymphoma—A Normal Tissue Complication Analysis of the HD16/17 Trial by the German Hodgkin Study Group.

Simple Summary: Patients with Hodgkin lymphoma show excellent survival rates, emphasizing the importance of the long-term side effects of the treatment itself. This analysis aims at a cardiopulmonary risk evaluation in the context of radiation treatment for early-stage Hodgkin lymphoma using normal tissue complication probability calculations. Overall, a low cardiopulmonary risk was estimated, not exceeding 2%. Concerning radiation dose, 30 Gy is associated with consistently higher risks as compared to 20 Gy. Further individualization of treatment will be attempted in the future. Purpose: Hodgkin lymphoma is a hematologic malignancy with excellent outcomes even in advanced stages. Consequently, the importance of treatment-associated toxicity increases. However, the exact estimation of individualized rates is difficult due to different disease extents, treatment strategies and techniques. The following analysis aims at a pre-treatment estimation of relevant mediastinal toxicities. Methods: Normal tissue complication probability calculations were used to evaluate the toxicity rates for the heart, lungs and female breast of patients undergoing radiotherapy for early-stage Hodgkin lymphoma. Overall, 45 Patients of the HD16 and HD17 trials by the German Hodgkin study group were included and risks were calculated using the Lyman–Kutcher–Burman model. Results: The median values for pericarditis, pneumonitis and fibrosis of the left or right breast were 0.0%, 0.0%, 0.7% and 0.6% in the HD16 cohort, and 0.0%, 0.1%, 1.1% and 1.0% in the HD17 cohort, respectively. Correspondingly, none of the included patients displayed any of the evaluated toxicities during clinical follow-up. The use of higher doses (30 Gy) in the HD17 cohort led to an increase in toxicity compared to the HD16 cohort (20 Gy). No significant influence of the planning target volume size or the radiation technique could be found in this study. Conclusion: Both the clinically observed and calculated toxicity rates corroborate the overall low-risk profile of radiotherapy for Hodgkin lymphoma. Further treatment individualization will be attempted in the future. [ABSTRACT FROM AUTHOR]