DID ATOMIC-BOMB RADIATION INFLUENCE THE INCIDENCE OF RETINOBLASTOMA IN NAGASAKI AND HIROSHIMA

The authors studied the effect of atomic bomb radiation in Nagasaki an d Hiroshima on the incidence of retinoblastoma by examining the histor y of exposure to atomic bomb radiation among the grandparents and pare nts of retinoblastoma patients in Nagasaki and Hiroshima. Of 85 patien ts born in Nagasaki Prefecture from 1965 to 1986 and in Hiroshima Pref ecture from 1966 to 1986, 42 had records of whether or not their grand parents and parents had been exposed to atomic bomb radiation. Seven h ad parents or grandparents exposed to atomic bomb radiation. These pat ients showed neither a high incidence of bilateral retinoblastoma nor a family history of retinoblastoma, although a higher incidence of can cer in the family history was found in the exposed group. Exposure to radiation showed no correlation with the onset of retinoblastoma. More over, the incidence of retinoblastoma in Nagasaki and Hiroshima Prefec tures was almost the same as the average incidence in Japan. The autho rs failed to find evidence of increased incidence of retinoblastoma in the offspring of those exposed to atomic bomb radiation in Nagasaki a nd Hiroshima. However, this does not mean that the effect of radiation on the occurrence of retinoblastoma can be ruled out.