Model diagram. Patients diagnosed with HL who respond to initial chemotherapy receive either no additional treatment (CT strategy) or low-dose radiation (CRT strategy). Patients may relapse and receive salvage therapy. Patients then face risks for late recurrence and/or treatment-specific excess second cancer and cardiac mortality late effects. *Late-recurrence risk spans from 3 years (treatment completion) to 10 years since initial diagnosis.¹²  Cumulative dosage for COPP/ABV × 4: cyclophosphamide, 2400 mg/m²; vincristine, 5.6 mg/m; procarbazine, 2800 mg/m²; prednisone, 2240 mg/m²; doxorubicin, 140 mg/m²; bleomycin, 40 IU/m²; and vinblastine, 24 mg/m².