Two hundred ninety patients with Hodgkin's disease pathologic stage (PS) I or II were treated in the prospective randomized trial of the Danish National Hodgkin Study (see Appendix) with radiotherapy +/- adjuvant combination chemotherapy. The initial tumor burden of each patient was assessed, combining tumor size of each involved region and number of regions involved. Multivariate analyses of prognostic factors including treatment, tumor burden, histologic subtype, pathologic stage, number of involved regions, mediastinal size, systemic symptoms, erythrocyte sedimentation rate (ESR), sex, and age were carried out. With regard to disease-free survival tumor burden was by far the most important prognostic factor for patients treated with adjuvant chemotherapy as well as for patients treated with radiotherapy alone. With regard to survival from Hodgkin's disease only tumor burden and age were independently significant. A combination of tumor burden, histologic subtype, and sex singled out patients with a high relapse rate both after radiotherapy only, and after radiotherapy plus chemotherapy. This combination also singled out patients destined to die from Hodgkin's disease more accurately than other prognostic factors.