Radiotherapy in younger patients with advanced aggressive B-cell lymphoma-long-term results from the phase 3 R-MegaCHOEP trial.

The role of consolidative radiotherapy (RT) for patients with aggressive B-cell lymphoma has not been fully elucidated. The R-MegaCHOEP trial investigated the use of high-dose chemotherapy and rituximab with subsequent autologous stem cell transplantations compared to conventional immunochemotherapy (R-CHOEP) for high-risk patients up to 60 years. The study protocol included RT for patients with bulky (maximum diameter ≥7.5 cm) or extranodal disease. Two-hundred sixty-one patients were analyzed, 120 of whom underwent RT. The most frequently irradiated regions were mediastinum (n = 50) and paraaortic (n = 27). Median RT dose was 36 Gray in median fractions of 1.8 Gray. Acute toxicities were mostly mild to moderate, with only 24 and 8 grade 3 and 4 toxicities reported during RT. Patients with bulky disease who received RT showed significantly better 10-year EFS, PFS and OS (EFS: 64% vs. 35%; p < 0.001; PFS 68% vs. 47%; p = 0.003; OS: 72% vs. 59%; p = 0.011). There was no significant increase in secondary malignancies with the use of RT. RT administered for consolidation of bulky disease after immunochemotherapy improved the prognosis of young high-risk patients with aggressive B-cell lymphoma and should be considered part of first-line therapy. The trial was registered with ClinicalTrials.gov, number NCT00129090.

Radiation Therapy in the German Hodgkin Study Group HD 16 and HD 17 Trials: Quality Assurance and Dosimetric Analysis for Hodgkin Lymphoma in the Modern Era.

Purpose: Radiation therapy (RT) is an integral part of treatment concepts for early-stage Hodgkin lymphoma. This analysis reports on RT quality in the recent HD16 and 17 trials of the German Hodgkin Study Group (GHSG). Methods and Materials: All RT plans of involved-node radiation therapy (INRT) in HD 17 were requested for analysis, along with 100 and 50 involved-field radiation therapy (IFRT) plans in HD 16 and 17, respectively. A structured assessment regarding field design and protocol adherence was performed by the reference radiation oncology panel of the GHSG. Results: Overall, 100 (HD 16) and 176 (HD 17) patients were eligible for analysis. In HD 16, 84% of RT series were evaluated as correct, with significant improvement compared with the predecessor studies (P < .001). In HD 17, 76.1% of INRT cases revealed a correct RT design compared with 69.0% of IFRT-cases, which was superior to previous studies (P < .001). Comparing INRT and IFRT, we found no significant differences in the percentage of any deviation (P = .418) or major deviations (P = .466). Regarding dosimetry, INRT was accompanied by an improvement in thyroid doses. Comparing different RT techniques, we found that intensity-modulated RT showed a reduction of high doses in the lung at the expense of an increased low-dose exposure in HD 17. Conclusions: The latest study generation of the GHSG demonstrates an improved quality in RT. A modern INRT design could be established without deterioration in quality. On a conceptual level, an individual consideration of the appropriate RT technique has to be performed.