Incidence of multiple myeloma in Nagasaki City

In order to observe the incidence of multiple myeloma in the population of Nagasaki City from 1973 to 1982, and to assess any influence caused by A-bomb exposure, 85 cases of myeloma have been collected and analysed. Informatively, 48 cases of this number were A-bomb survivors. Among the middle-aged cases, the crude incidence rates of myeloma in the exposed group were found to be higher than those in the non-exposed group. Further, the relative risk of myeloma was higher in A-bomb survivors and this tendency become more pronounced in the those who were within 2 km of the epicenter of the blast. The age-adjusted relative risk in male and female A-bomb survivors was 1.59 and 1.68 respectively, but no significant differences were noted. (author)