Age-specific familial risks for renal cell carcinoma with evidence on recessive heritable effects.
BACKGROUND
Systematic comparisons of mode of inheritance for renal cell carcinoma (RCC) have not been carried out. The occurrence of cancer in parents and offspring may be due to dominant causes, whereas cancer affecting only siblings may indicate a recessive causation. Environmental effects need to be excluded.


METHODS
The Swedish Family-Cancer Database includes all Swedes born after 1931 with their biologic parents, totaling 10.2 million persons. Cancer data were retrieved from the Swedish Cancer Registry from years 1961 to 2000, included 2415 cases of RCC in offspring and 18531 in parents. Standardized incidence ratios (SIRs) and 95% CI limits were calculated for offspring whose parents or sibling were diagnosed with RCC.


RESULTS
The SIRs for siblings for RCC depended on their age difference. SIR was 7.63 (95% CI 3.63-14.08) when the age difference was less than 3 years and compared to 3.43 (95% CI 1.77-6.02) for large age difference. SIRs for familial risk of RCC were 1.73 (95% CI 1.31-2.26) when a parent and 4.58 (95% CI 2.87-6.94) when a sibling had RCC. Age-specific analysis of familial RCC among siblings revealed maxima at ages 40 to 49 and 60 to 68 years.


CONCLUSIONS
The findings in the present study offer evidence on recessive effects in early onset RCC.
Hemminki
Kari
K
Department of Biosciences at Novum, Karolinska Institute, Huddinge, Sweden.
Li
Xinjun
X
D000293:Adolescent; D000328:Adult; D000367:Age Factors; D017668:Age of Onset; D000368:Aged; D002292:Carcinoma, Renal Cell / Q000453:epidemiology* / Q000235:genetics*; D002648:Child; D002675:Child, Preschool; D016208:Databases, Factual; D005260:Female; D005808:Genes, Recessive; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007680:Kidney Neoplasms / Q000453:epidemiology* / Q000235:genetics*; D008297:Male; D008875:Middle Aged; D012042:Registries; D012307:Risk Factors; D013548:Sweden / Q000453:epidemiology