Adcetris (Brentuximab Vedotin), Combination Chemotherapy, and Radiation Therapy in Treating Younger Patients With Stage IIB, IIIB and IV Hodgkin Lymphoma

PRIMARY OBJECTIVES: * To evaluate the safety of brentuximab vedotin, etoposide, prednisone and doxorubicin hydrochloride (AEPA)/cyclophosphamide, brentuximab vedotin, prednisone and dacarbazine (CAPDac), as well as the efficacy (early complete response) after 2 cycles of AEPA chemotherapy in high risk patients with Hodgkin lymphoma (HL). * To compare the event-free survival in high risk HL patients treated with AEPA/CAPDac to the historical control unfavorable risk 2 arm (UR2) of the St. Jude HOD99 study. SECONDARY OBJECTIVES: * To estimate the number of patients with adequate response according to the definitions in the Euro-Net C1 after 2 cycles of AEPA. * To evaluate the safety of Adcetris (brentuximab vedotin) in the AEPA/CAPDac regimen in children with high risk HL. * To describe acute hematologic, neuropathic, and infectious toxicities as they relate to transfusion requirements, growth factor support, episodes of febrile neutropenia and hospitalizations, according to the National Cancer Institute (NCI) Common Terminology Criteria for Adverse Events (CTCAE), version 4.0. * To study the association between local failure and original lymph node region and volume of radiation (patterns of treatment failure). * To assess patient-reported symptoms and health-related quality of life in children with high risk HL compared to those treated on the unfavorable treatment arm of the St. Jude HOD99 study. OUTLINE: AEPA REGIMEN: Patients receive brentuximab vedotin on days 1, 8, and 15, etoposide on days 1 to 5, prednisone three times daily (TID) on days 1 to 15, and doxorubicin hydrochloride on days 1 and 15. Treatment repeats every 28 days for 2 courses in the absence of disease progression or unacceptable toxicity. CAPDac REGIMEN: Patients receive cyclophosphamide on days 1 and 8, brentuximab vedotin days 1 and 8, prednisone TID on days 1 to 15, and dacarbazine on days 1 to 3. Treatment repeats every 21-28 days for 4 courses in the absence of disease progression or unacceptable toxicity. Beginning 2-3 weeks after CAPDac chemotherapy, patients with lymph nodes that do not go into remission after 2 courses of AEPA chemotherapy undergo radiation therapy daily, 5 days a week for 3-4 weeks. After completion of study treatment, patients are followed up every 3 months for 1 year, every 4 months for 2 years, every 6 months for 2 years, and then annually for 5 years.