OBJECTIVETo investigate the association between urinary levels of isothiocyanates (ITCs) and the risk of pancreatic cancer in urban Shanghai.

METHODSA case-control study has been conducted in urban Shanghai. The cases (from December 2006 to December 2008) were identified through an newly established "instant case reporting" system. The high performance liquid chromatography (HPLC) method was applied to determine the urinary levels of isothiocyanates in 390 cases and 414 controls. A food-frequency questionnaire was administered to estimate cruciferous vegetables consumption and dietary ITC exposure.Non-conditional logistic regression model was used to analyze the relationship between dietary and urinary levels of isothiocyanates and the risk of pancreatic cancer.

RESULTSThe cruciferous vegetables intake and ITC consumption, urinary ITC levels (median (P25, P75)) were 95.0 (66.9, 135.8) g/d, 11.0 (7.1, 16.0) µmol/d, 0.95 (0.12, 2.92) µmol/g Cr respectively in cases, all lower than those in controls, separately 107.4 (80.1, 154.1) g/d, 12.3 (8.0, 18.0) µmol/d, 1.78 (0.53, 5.28) µmol/g Cr. The differences were statistically significant (t = 3.75, 3.03, 4.40, all P values <0.01). Urinary levels of ITCs in controls were correlated with cruciferous vegetables consumption and dietary ITC exposure (r = 0.189, 0.201, all P values <0.01). There was inverse association between urinary ITCs and the risk of pancreatic cancer after adjusting for possible confounding factors such as age, sex, history of diabetes and pancreatitis. Compared with the first tertile (<0.825 µmol/g Cr), the odds ratio (95%CI) for the second (0.825-3.342 µmol/g Cr) and third tertiles ( ≥ 3.343 µmol/g Cr) were 0.69 (0.49-0.97) and 0.47(0.33-0.68), respectively, Ptrend<0.01.High levels of cruciferous vegetables or ITC consumption were associated with a reduced risk of pancreatic cancer (all P trend <0.05).

CONCLUSIONindicated that high levels of dietary ITC exposure might reduce the risk of pancreatic cancer.