The Role of Radiotherapy in Hematologic Malignancies in Children, Adolescents, and Young Adults.

Hematologic cancers in pediatric, adolescent, and young adult populations include a diverse spectrum of malignancies. The cornerstone of treatment is multiagent chemotherapy. While radiation therapy (RT) is highly effective and played a pivotal role historically, its use has evolved. In classic HL, advancements in systemic therapy have allowed for reduced RT volumes and doses and careful patient selection. Similarly, NLPHL management has shifted toward observation after complete resection, or limited chemotherapy after incomplete resection with RT used only for partially responding disease sites. In primary mediastinal B-cell lymphoma, the role of RT is an area of active study, and treatment with chemotherapy alone has shown promise in adults. Frontline treatment of diffuse large B-cell lymphoma and Burkitt lymphoma relies on chemotherapy; evidence do not support a role for consolidative RT. In leukemia, the use of prophylactic cranial and testicular RT is declining in the setting of modern chemotherapy regimens. RT may play an important role in the salvage of relapsed/refractory lymphomas and leukemias. In addition, palliative RT is often integral to symptom relief and function preservation. Future research aims to refine risk stratification, personalize treatment approaches, and incorporate novel therapies to maintain or improve oncologic outcomes while mitigating late effects.