Leukemia in Twins World-wide review of clinical cases

Abstract

We undertook an extensive review of world-wide clinical reports of leukemia in twins. Our survey was a careful one; exclusions are inevitable, but, if so, are inadvertent, except for undocumented “personal communication” cases. These have sometimes been included in large reviews of either leukemia or leukemia in twins. Also excluded are cases mentioned only tangentially in reports of cancer in large population groups, if no clinical details were given. In some instances, we were able to adapt available clinical information to our tables.Leukemia appears to occur at four periods in the lives of twins: (1) the perinatal-congenital period; (2) early childhood; (3) late childhood; and (4) adulthood. Those cases occurring around the time of birth and the first year of life are combined under the title: Perinatal-Congenital. In Tab. I, Early Childhood extends from about 2 to 7 years, and Late Childhood from 7 through 12 years. All other cases have been considered as Adult. Two cases occurring in teenagers have been placed in this group in accordance with clinical practice. We have compiled 62 cases of leukemia in twins from clinical reports from the world publications in the following categories: Perinatal-Congenital, 15; Early Childhood, 26; Late Childhood, 9; Adulthood, 12. Comparative clinical details of all these cases will be published in a subsequent report.Except for those instances about which writers admitted that the diagnosis of zygosity was in question, most reported clinical cases occurred in MZ twins. There were 39 cases of leukemia in MZ twins, 13 cases in DZ twins and 10 cases in whom zygosity was in doubt.