A retrospective analysis of 117 cases of Hodgkin's disease treated at the Centre G.F. Leclerc between 1976 and 1985 was performed with three objectives: 1): to re-evaluate the histologic subtype by the Lukes-Rye classification according to recent data; 2): to demonstrate the frequency of CD 15 antigen by an indirect, three stage immunoperoxidase technique on initial node biopsy histologic sections; 3): to study the prognostic value of this antigen. Histologic reclassification disclosed that 9 cases were in fact non Hodgkin's lymphoma. The remaining 108 cases were classified as lymphocyte predominant (n = 11), nodular sclerosis (n = 77), and mixed cellularity (n = 17), with no cases of either lymphocyte depletion or nodular paragranuloma of Poppema and Lennert identified. In these specimens, fixed in Bouin's solution and embedded in paraffin, CD 15 antigen was detected in the Reed-Sternberg cells and the mononuclear variety of Hodgkin cells in 64 patients (59%). The presence of this antigen was independent of histologic subtype, patient age or sex, clinical stage and the presence of systemic symptoms. Both actuarial disease-free and overall survivals showed that the prognosis of Hodgkin's disease is more favorable in CD 15 positive cases.