The advanced forms of multiple myeloma of bone, stage III, or those with a large tumoral mass, characterized by a considerable number of myeloma-cells, pose difficult problems in treatment. Little progress has been made since the introduction of the alkylating agents, and combined chemotherapy does not seem to be any more effective in terms of survival. It is these severe forms that culminate in painful symptoms which are often difficult to eliminate. The radiosensitivity of myeloma led us to treat 20 patients affected by severe forms of the disease by total body irradiation in two stages, and we analyse here the effects of treatment and the tolerance for this technique.