Statistical observation on autopsy cases of malignancy at the Japanese Red Cross, Nagasaki Atomic Bomb Hospital

Statistical observation was made as to autopsy cases of atomic-bomb survivors in Nagasaki. The total of autopsy cases at the Japanese Red Cross, Nagasaki Atomic Bomb Hospital from the opening of the hospital, 1968, to December in 1975 was 1,486 cases (autopsy rate, 65.1%) in which 880 cases of atomic bomb survivors (autopsy rate, 68.0%) were contained. Cases of malignancy totaled 829 and 528 cases of those were atomic bomb survivors. Cases of malignancy were divided into three groups, that is, group exposured to atomic bomb at place within 2 km from the explosion place, group exposured at place from more than 2 km or entering after explosion into the city, and not-exposured group. Relationship between main malignancies and exposure was discussed, and the following results were obtained. 1) Obvious relationship was found to exist between exposure and acute and chronic medullary leukemia. 2) Malignant lymphoma was scarecely correlated with exposure, but its occurrence rate was higher than the mean rate in Japan in reflection the region where this disease occurs much geographically. 3) Relationship between exposure and stomach cancer, lung cancer, cancer of the large intestine, and double cancer was not found obviously, but occurrence rate of hepatic cancer was higher than the mean rate in Japan in three groups. The reason was supposed to be geographical factor. 4) Cases of thyroid gland cancer were a small number in female of the group exposured within 2 km, and cases of prostate cancer were a small number in the group within 2 km, but their occurrence rate was high specifically. (Tsunoda, M.)