[Relationship between serum hepatitis B virus DNA load and hepatocellular carcinoma in Qidong, China: a cohort follow-up study of 14 years].

OBJECTIVE: To explore the relationship between serum HBV DNA load and hepatocellular carcinogenesis in Qidong HBsAg carriers. METHODS: In 1997, 477 HBsAg carriers and 477 age, gender and residence matched HBsAg negative controls were enrolled as a prospective cohort in Qidong city. The entry serum samples were detected for the levels of HBeAg and HBV DNA. The relationship between baseline HBV DNA load and hepatocellular carcinoma (HCC) during the follow-up period from June 1997 to June 2011 were analyzed. RESULTS: The total observed person-years (PY) were 12 200. Eighty-seven patients developed HCC with an incidence of 1498/100 000 PY in the HBsAg positive group versus 6 with an incidence of 94/100 000 PY (P = 0.000) in the HBsAg negative group. The relative risk (RR) was 15.96. N o significant difference existed between the incidences of other tumors in two groups (P = 0.161). Compared with the HBsAg negative group, the RR of HCC was 11.38 (95%CI 4.87 - 26.62, P < 0.01)in the HBsAg+/HBeAg- group and 29.08 (95%CI 12.37 - 68.37, P < 0.01) in the HBsAg+/HBeAg+ group; 5.80 (95%CI 2.29 - 14.70, P < 0.01) in the HBsAg+/HBV DNA- group and 27.75 (95%CI 12.07 - 63.81, P < 0.01) in the HBsAg+/HBV DNA+ group. In HBsAg positive subjects, while the HBV DNA load was classified into 5 levels namely 250 - 10(4), 10(4)-, 10(5)-, 10(6)- and ≥ 10(7) copies/ml, the relative risks for HCC at each level were 2.84 (95%CI 1.44 - 5.61, P < 0.01), 5.75 (95%CI 2.77 - 11.95, P < 0.01), 9.05 (95%CI 4.71 - 17.41, P < 0.01), 6.39 (95%CI 2.79 - 14.64, P < 0.01) and 4.35 (95%CI 2.21 - 8.56, P < 0.01) respectively versus the < 250 copies/ml group. CONCLUSION: HBV DNA is an important risk predictor of hepatocellular carcinoma. The HBsAg carriers with the serum loads of HBV DNA between 10(5) - 10(6) copies/ml are most likely to present with HCC.

[Longitudinal study of aflatoxin exposure in the development of primary liver cancer in patients with chronic hepatitis].

OBJECTIVE: To study the relationship between aflatoxin exposure and the development of primary liver cancer (PLC) in patients with chronic hepatitis. METHODS: A 21-year longitudinal study was carried out in a large cohort of 515 PLC high-risk individuals with HBV infection in PLC high prevalence region. RESULTS: (1) The PLC year-incidence of cohort was 1437.25/100,000. And it was significantly higher than that of the same natural peoples (184. 53/100,000, P = 0.000, RR = 7.79). There was no significant difference in the incidence of other tumors between these two groups (P = 0.576). (2) The PLC patients in the cohort were diagnosed at an average age 1.4 year younger than those in the same natural peoples and had an average survival of 6.42 months longer than the latter. (3) The PLC year-incidence of those with the exposure to aflatoxin was significantly higher than that of unexposed people (2784. 96/100,000 vs. 1251.02/100,000, P = 0.008, RR = 2.23). There was no relationship between the incidence rate of other tumors and the aflatoxin exposure. (4) The PLC year-incidence of aflatoxin-exposing people increased with the rising urine excretion of AFM1. When the urine excretion of AFM1 was more than 100 ng during 24 hours, the PLC year-incidence was high as 4717.82/100,000. The urine excretion of AFM1 was also obviously related with the abnormal liver function (P = 0.035). There was no relationship with the positive rate of HBeAg (P = 0.812). (5) The PLC year-incidence of those with the exposure to aflatoxin were infected with HBV (2 784. 96/100 000) significantly higher than that of cohort people (P = 0.001) and the same natural peoples (P = 0.000, RR = 15.09). (6) It took an average time of 14.65 years (median 13.68) from hepatitis occurrence to PLC diagnosis and 7.38 years (median 6.40) from liver cirrhosis to PLC diagnosis. CONCLUSION: HBV infection is a main etiological factor of PLC and the aflatoxin exposure has obvious synergistic effect in the carcinogenesis of PLC. Regular observation in a PLC high-risk cohort is effective for an early diagnosis and treatment. Hepatitis control and aflatoxin de-pollution is effective to inhibit the occurrence of PLC.

Effects of glucosinolate-rich broccoli sprouts on urinary levels of aflatoxin-DNA adducts and phenanthrene tetraols in a randomized clinical trial in He Zuo township, Qidong, People's Republic of China.

Residents of Qidong, People's Republic of China, are at high risk for development of hepatocellular carcinoma, in part due to consumption of aflatoxin-contaminated foods, and are exposed to high levels of phenanthrene, a sentinel of hydrocarbon air toxics. Cruciferous vegetables, such as broccoli, contain anticarcinogens. Glucoraphanin, the principal glucosinolate in broccoli sprouts, can be hydrolyzed by gut microflora to sulforaphane, a potent inducer of carcinogen detoxication enzymes. In a randomized, placebo-controlled chemoprevention trial, we tested whether drinking hot water infusions of 3-day-old broccoli sprouts, containing defined concentrations of glucosinolates, could alter the disposition of aflatoxin and phenanthrene. Two hundred healthy adults drank infusions containing either 400 or < 3 micromol glucoraphanin nightly for 2 weeks. Adherence to the study protocol was outstanding; no problems with safety or tolerance were noted. Urinary levels of aflatoxin-N(7)-guanine were not different between the two intervention arms (P = 0.68). However, measurement of urinary levels of dithiocarbamates (sulforaphane metabolites) indicated striking interindividual differences in bioavailability. An inverse association was observed for excretion of dithiocarbamates and aflatoxin-DNA adducts (P = 0.002; R = 0.31) in individuals receiving broccoli sprout glucosinolates. Moreover, trans, anti-phenanthrene tetraol, a metabolite of the combustion product phenanthrene, was detected in urine of all participants and showed a robust inverse association with dithiocarbamate levels (P = 0.0001; R = 0.39), although again no overall difference between intervention arms was observed (P = 0.29). Understanding factors influencing glucosinolate hydrolysis and bioavailability will be required for optimal use of broccoli sprouts in human interventions.