(HealthDay)—Smoking is a risk factor for clear cell and papillary renal cell carcinoma, but not for the chromophobe subtype, according to a study published in the September issue of The Journal of Urology.

Neel H. Patel, M.D., from the State University of New York in Buffalo, and colleagues examined the correlation between smoking and subtype. Data were collected from 816 patients with nonfamilial renal cell carcinoma (705) or benign pathology (111) undergoing nephrectomy.

The researchers found that 51 percent of patients reported smoking, including 21 percent active smokers and 30 percent former smokers. Compared with benign histology, active smoking was more common with clear cell or papillary cell carcinoma (23 and 26 percent, respectively, versus 14 percent; P < 0.05 each). Active smoking was less common with chromophobe renal cell carcinoma (6 percent; P < 0.05 versus clear cell or papillary). Any history was also less common with chromophobe versus clear cell or papillary histology (26 percent versus 53 percent [P = 0.003] or 58 percent [P = 0.001]). For clear cell and papillary histologies, but not chromophobe histology, independent associations with persisted after multivariable adjustment (odds ratios, 2.2 and 2.4, respectively; both P < 0.05).

"These findings underscore distinct carcinogenic mechanisms underlying the various renal cell carcinoma subtypes," the authors write.