This Article Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Google Scholar Articles by Moy, K. A. Articles by Yu, M. C. PubMed PubMed Citation Articles by Moy, K. A. Articles by Yu, M. C.

Urinary Total Isothiocyanates and Colorectal Cancer: A Prospective Study of Men in Shanghai, China

¹ The Masonic Cancer Center, University of Minnesota, Minneapolis, Minnesota; ² Lombardi Comprehensive Cancer Center, Georgetown University, Washington, District of Columbia; ³ USC/Norris Comprehensive Cancer Center, University of Southern California, Los Angeles, California; and ⁴ Department of Epidemiology, Shanghai Cancer Institute, Shanghai, People's Republic of China

Requests for reprints: Jian-Min Yuan, Division of Epidemiology and Community Health, University of Minnesota, 1300 South 2nd Street, Suite 300, Minneapolis, MN 55455. Phone: 612-625-8058; Fax: 612-624-0315. E-mail: jyuan{at}umn.edu

Laboratory and epidemiologic evidence suggests that dietary isothiocyanates (ITCs) may have a chemopreventive effect on cancer. Humans are exposed to ITCs primarily through ingestion of cruciferous vegetables that contain glucosinolates, the precursors to ITCs. The association between urinary total ITC level and colorectal cancer risk was examined in a cohort of 18,244 men in Shanghai, China, with 16 years of follow-up. Urinary total ITCs were quantified on 225 incident cases of colorectal cancer and 1,119 matched controls. Odds ratios (ORs) and their 95% confidence intervals (95% CIs) were calculated using logistic regression models. High levels of urinary total ITCs were associated with a reduced risk of colorectal cancer 5 years after baseline measurements of ITCs, whereas a statistically nonsignificant increase in the risk of colorectal cancer was observed for cases within 5 years of post-enrollment (OR, 1.93; 95% CI, 0.85-4.39 for the upper three quartiles of urinary ITCs versus the lowest quartile). The inverse ITC-colorectal cancer association became stronger with a longer duration of follow-up. Compared with the first quartile, ORs (95% CIs) for the second, third, and fourth quartiles of total ITCs in urine collected 10 or more years before cancer diagnosis were 0.61 (0.35-1.05), 0.51 (0.29-0.92), and 0.46 (0.25-0.83), respectively, for risk of colorectal cancer (P for trend = 0.006). The present study suggests that dietary ITCs may exert tumor inhibitory effects, especially during earlier stages of the multistage process of carcinogenesis. (Cancer Epidemiol Biomarkers Prev 2008;17(6):1354–9)