Increased risk of cancer among siblings of long-term childhood cancer survivors: a report from the childhood cancer survivor study.
We determined risk of cancer among first-degree relatives of 5-year survivors of childhood leukemia, lymphoma, central nervous system tumors, sarcomas, Wilms' tumor, and neuroblastoma. Subjects were 13,703 participants in the Childhood Cancer Survivor Study. Family history was collected on 56,759 first-degree relatives using a self-reported questionnaire. Incidence was compared with age- and sex-specific rates using the U.S. Surveillance, Epidemiology and End Results program. Siblings of the survivors had an increased risk of cancer [standardized incidence ratio (SIR), 1.5; 95% confidence interval (95% CI), 1.35-1.7]. Risk was elevated for siblings of probands of leukemia (SIR, 1.3; 95% CI, 1.0-1.6), Hodgkin's disease (SIR, 1.5; 95% CI, 1.2-1.9), non-Hodgkin's lymphoma (SIR, 1.8; 95% CI, 1.3-2.5), Wilms' tumor (SIR, 1.9; 95% CI, 1.2-3.2), soft tissue sarcoma (SIR, 1.5; 95% CI, 1.0-2.2), and bone tumors (SIR, 1.6; 95% CI, 1.2-2.2). Cancer risk was elevated in siblings (SIR, 2.4; 95% CI, 1.5-3.7) and offspring (SIR, 15.0; 95% CI, 5.3-42.9) of probands with second malignant neoplasms (SMN) compared with relatives of probands without SMNs. Siblings of probands with leukemia, Hodgkin's disease, neuroblastoma, and Wilms' tumor had elevated risks for the same malignancies. Parents had no increased risk (fathers' SIR, 0.7; 95% CI, 0.7-0.8; mothers' SIR, 0.9; 95% CI, 0.9-1.0). Seventy percent of siblings' cancers developed in adulthood. These findings suggest that familial cancer syndromes may be revealed as this cohort and family members age and with accrual of more offspring and subjects with SMNs.
Friedman
Debra L
DL
University of Washington and Fred Hutchinson Cancer Research Center, Suite D5-280, 1100 Fairview Avenue North, Seattle, WA 98109, USA. dfriedma@fhcrc.org
Kadan-Lottick
Nina S
NS
Whitton
John
J
Mertens
Ann C
AC
Yasui
Yutaka
Y
Liu
Yan
Y
Meadows
Anna T
AT
Robison
Leslie L
LL
Strong
Louise C
LC
D002648:Child; D005190:Family; D005260:Female; D006801:Humans; D015994:Incidence; D008297:Male; D009369:Neoplasms / Q000453:epidemiology / Q000401:mortality*; D012306:Risk; D035781:Siblings; D011795:Surveys and Questionnaires; D017741:Survivors / Q000706:statistics & numerical data*