Correspondence
Cancer among Offspring of Survivors of Childhood Cancer
N Engl J Med 1998; 339:923-924September 24, 1998
- Article
To the Editor:
In the article by Sankila et al. (May 7 issue)1 on the occurrence of cancer among the offspring of childhood-cancer survivors, a total of 44 cancers were diagnosed among 5847 offspring of 14,652 survivors. After excluding 22 cases associated with familial cancer syndromes (retinoblastoma and the Li–Fraumeni syndrome) or predisposing genetic conditions (neurofibromatosis and von Hippel–Lindau disease), the authors calculated a standardized incidence ratio of 1.3 (95 percent confidence interval, 0.8 to 2.0). Sankila et al. suggest that there was no evidence of an increased risk of nonhereditary cancer among the offspring of survivors of childhood cancer. They further suggest that efforts to screen such offspring are unwarranted.
A notable omission in these data is information regarding the treatment the survivors received for the primary cancer. We presume that at least some of the group received chemotherapy or radiation therapy as treatment for their cancers, and details of their therapy are needed in order to interpret these data. Because this study included patients treated as early as 1955, the treatment experience of these patients is likely to have been considerably different from that of a patient receiving a diagnosis in the 1990s. Moreover, the distribution of diagnoses in a population of survivors in the 1990s will differ from that of a cohort of survivors from the 1950s. In the absence of data regarding the treatment the survivors received and an acknowledgment regarding changes in patterns of diagnosis, this article cannot be used to reassure patients currently receiving therapy.
1 ReferencesJulie A. Ross, Ph.D.
Stella M. Davies, M.B., B.S., Ph.D.
University of Minnesota, Minneapolis, MN 554551
Sankila R ,Olsen JH ,Anderson H , et al. Risk of cancer among offspring of childhood-cancer survivors. N Engl J Med 1998;338:1339-1344
Full Text | Web of Science | Medline
Author/Editor Response
The authors reply:
To the Editor: The most important message of our study was that we can reassure the generations of childhood-cancer survivors that we were able to include in the study population, because there was no apparent excess risk of sporadic cancer among their offspring. The survivors of childhood cancer who were treated in the past are now of reproductive age.
Drs. Ross and Davies suggest that our study cannot be used to reassure patients receiving current therapies. In principle, they are correct. We must wait between 10 and 40 years to determine the incidence of cancer in the offspring of patients who are treated for childhood cancer today. We can update our study whenever it is considered necessary. If any excess risk starts to emerge in future studies, we can initiate a nested case–control study focusing on treatments. Regarding the rarity of any parent–offspring pairs with sporadic cancers, this work will require very large patient populations and possibly global collaboration.
Risto Sankila, M.D.
Finnish Cancer Registry, FIN-00170 Helsinki, FinlandJørgen H. Olsen, M.D., Ph.D.
Danish Cancer Society, DK-2100 Copenhagen, DenmarkStanislaw Garwicz, M.D., Ph.D.
University Hospital, S-221 85 Lund, Sweden
