To examine the association between body mass index and renal cell carcinoma
risk, we analyzed data from a case-control study of members of a health ma
intenance organization in western Washington State. We identified cases dia
gnosed between 1980 and 1995 through a population-based cancer registry. We
selected controls from membership files. We collected adult weight and hei
ght from medical records. Increased body mass index was associated with inc
reases in risk for both men and women (for the top quartile relative to the
bottom quartile of maximum body mass index: in women, OR = 3.3, 95% CI = 1
.2-8.7; in men, OR = 2.3, 95% CI = 1.2-4.5).