[en] The incidence of primary site and histological type of malignant lymphoma and the relationship to the atomic bomb exposure in Nagasaki City were investigated in a population of age over 30 years during 1973 to 1982. Of 365 cases (male 207, female 158) of malignant lymphoma reported, 142 (male 66, female 76) had the atomic bomb exposure. No significant difference in incidence of malignant lymphoma was found between the exposed and non-exposed groups. Primary sites of non-Hodgkin lymphoma were: lymph nodes; male exposed, 66; non-exposed, 67%; female exposed, 50%; non-exposed, 69%, gastrointestinal (G.I.) tract, male exposed, 14%; non-exposed, 11%; female exposed, 21%; non-exposed, 17%. histological reexamination of 232 cases according to the National Cancer Institute (USA) criteria yielded: diffuse large cell type, 27.2%; large cell immunoblastic type, 28.0%. No significant difference in these items was found between the exposed and the non-exposed groups. A comparison to the Hiroshma data revealed that an atomic bomb survivor does not show higher incidence in Nagasaki but in Hiroshima. (author)