In a series of 129 patients with Hodgkin's disease the presence of previously described abnormal cells in the peripheral blood correlated closely with splenic or bone marrow involvement. These cells are therefore regarded as a fairly reliable indicator for Hodgkin's invasion of the spleen. In these cases both parameters point to hematogenous dissemination or a multicentric origin of the disease. The results of therapy in connection with these findings are discussed. It is felt that the choice of treatment is facilitated in this way.