459 JOURNAL OF SCIENCE, Hue University, N 0 61, 2010 RESEARCH ON CHRONIC HBV INFECTION AND RISK FACTORS IN PATIENTS WITH LIVER CANCER IN THE HOSPITAL OF HUE COLLEGE OF MEDICINE AND PHARMACY Vo Dang Anh Thu, Nguyen Thi Kim Hoa, Pham Van Linh College of Medicine and Pharmacy, Hue University SUMMARY Research on the risk factors of liver cancer, particularly HBV infection is necessary for preventing liver cancer and to reduce the prevalence of this cancer in future. Objectives: To identify the risk factors among patients with liver cancer in Hue college of Medicine and Pharmacy. Methods: A case-control study was conducted from May 2007 to May 2008 in which there were 40 patients with liver cancer and 40 people without any liver diseases. For each patient, there was a person in the control group has the same age, gender and living areas. Results: (1) The average age of the study subjects was 53.7±8.9 in which age 54.3±12.1 was the mean for men and age 52.9±8.9 for women, 50% of liver cancer patients aged from 45 to 60. The ratio of men to women was 3 to 1. (2) The risk factors of liver cancer include: HBsAg (+) (OR = 17.0), history of alcohol consumption (OR=7.0), drinking frequency (OR=4.5), the volume of alcohol intake (OR=5.18), tobacco consumption (OR = 2.51), familial history of liver cancer (OR = 5.52). (3) The exposure to organic pesticides is not associated with liver cancer (OR=1.48, p>0.05, χ 2 = 0.39). Conclusion: This research was useful in identifying risk factors of liver cancer. The results from this research will be used to inform the community and future study of the risk factors of liver cancer. 1. Introduction Liver cancer is one of the most common cancers worldwide. This is the fifth most common cause of cancer in men and the eighth most common cause in women. In Vietnam, liver cancer is also a common and serious cancer that affects men more often than women, and which was ranked the third most common cancer in men and the sixth in women. As in many Asian countries, Vietnam is one of the countries that have a high prevalence of liver cancer due to the high proportion of hepatitis B and C infection. Major risk factors of hepatocellular carcinoma are hepatitis B and C. Thereto, alcohol and cirrhosis also largely contribute to the causes of this serious cancer. One study has shown that alcoholics were two times more likely than non-alcoholics to develop liver cancer, and twenty-two times more likely to develop liver cancer if there 460 was cirrhosis induced by alcohol. Meanwhile, aflatoxin B1 is the main causal factor of live cancer due to chemicals. Research on risk factors of liver cancer, particularly HBV infection are necessary for preventing liver cancer and contributing to the reduction in the prevalence of this cancer in the future. This study was conducted in order to determine the relationship between chronic hepatitis B virus infection and other risk factors among patients with liver cancer. 2. Methodology A case-control study was done from May 2007 to May 2008. 2.1. Sample Using the formula of Schlesselman 3 : Predicted: f = 0.35; OR = 3.5; accepted:  = 0.05;  = 0.2; → n  40 2.2. Selection of cases and controls The cases were 40 patients with liver cancer who were under treatment at the hospital of Hue college of Medicine and Pharmacy. Under the principle of the same living area, sex and age, 40 non-liver cancer subjects were selected as controls. Consequently, the study subjects include 40 cases and 40 controls. 2.3. Contents of the study The study contents composed of three parts as follow: (1).General characteristics; (2). Personal habits: including alcohol consumption and cigarette smoking; (3). Symptoms and disease history related with liver cancer. 2.4. Investigation methods the constructed questionnaire was used to collect data. All interviewers were trained focusing on the skills of interviewing the subjects. No subjects refused to be interviewed. 2.5. Statistical analysis Classical analysis methods of case-control study was used to analyze data. OR value and χ 2 were calculated. In this study, the EPI INFO 6.04 was used for completing all the statistical analyses.         2 3 2 33βα pf qpf1fZu12uZ n              1ORf1 OR 1f 2 1 u     1ORf1 fOR p 3   33 p1q  461 3. Results Table 1. Age Age Frequency % 15 - 30 0 0 > 30 - 45 10 25 > 45 - 60 20 50 > 60 10 25 Sum 40 100 *There was 50% liver cancer patients aged 45-60. Table 2. Sex Sex Frequency % Male 30 75.0 Female 10 25.0 Sum 40 100 *Men have higher proportion of liver cancer than women; the ratio of men to women is three to one. Table 3. The situation of hepatitis B infection among patients with liver cancer HBsAg Cases n % (+) 30 75.0 (-) 10 25.0 Sum 40 100 *75% patients with liver cancer have HBsAg (+) Table 4. The relation between hepatitis B infection and liver cancer Cases Controls HBsAg(+) 30 6 36 HBsAg(-) 10 34 44 40 40 80 462 OR = 17.0 95%CI of OR = (4.91 – 62.64) χ 2 = 29.1 p < 0.001 Table 5. The relation between contracting hepatitis B in history and liver cancer Cases Controls Yes 14 3 17 No 26 37 63 40 40 80 OR = 6.64 95%CI of OR = (1.55 – 32.62) χ 2 = 9.04 p < 0.01 Table 6. The relation between history of alcohol consumption and liver cancer Cases Controls Yes 30 12 42 No 10 28 38 40 40 80 OR = 7.00 95%CI of OR = (2.36 – 21.39) χ 2 = 16.24 p < 0.001 Table 7. The relation between alcohol drinking frequency and liver cancer Cases Controls Frequent 18 3 21 No frequent 12 9 21 30 12 42 OR = 4.50 95%CI of OR = (0.84 – 26.75) 463 χ 2 = 4.20 p < 0.05 Table 8. The relation between the daily volume of alcohol intake and liver cancer Cases Controls ≥ 30 gammes 19 3 22 < 30 gammes 11 9 20 30 12 42 OR = 5.18 95%CI of OR = (0.96 – 31.12) χ 2 = 5.05 p < 0.05 Table 9. The relation between history of exposure to chemicals and liver cancer Cases Controls Yes 7 5 12 No 33 35 68 40 40 80 OR = 1.48 95%CI of OR = (0.37 – 6.09) χ 2 = 0.39 p > 0.05 Table 10. The relation between history of tobacco smoking and liver cancer Cases Controls Smoking 26 17 43 Non-smoking 14 23 37 40 40 80 OR = 2.51 95%CI of OR = (0.93 – 6.88) χ 2 = 4.07 p < 0.05 464 Table 11. The relation between family history with liver cancer and liver cancer Cases Controls Yes 9 2 11 No 31 38 69 40 40 80 OR = 5.52 95%CI of OR = (0.99 – 40.12) χ 2 = 5.16 p < 0.05 4. Discussion 4.1 General characteristics Age In this study, there was no patient under thirty years old and the average age of the subjects was 53.7±8.9 in which 54.3±12.1 for men and 52.9±8.9 for women. Of the 40 cases, there were 20 (50%) patients aged from 46 to 50. This figure is approximate with previous national and international studies. Sex Men are more likely to contract liver cancer than women. The ratio of male patients to female patients in this study was 3 to 1. Several studies have suggested that hormone androgen facilitates the development of the tumors, whereas oestrogen in women has a protective effect. In addition, men have greater risk factors of liver cancer than women including smoking and alcohol consumption. 4.2 The relation between chronic hepatitis B virus infection and liver cancer The prevalence of patients with liver cancer having HBsAg (+) was 75 percent. Meanwhile, in the control groups, there were only 15 percent of the subjects having HBsAg (+). Therefore, patients who have HBsAg (+) get the higher risk of contracting liver cancer than people with HBsAg (-) (OR = 17, p <0.01, χ2 = 29.1). 4.3. Other risk factors of liver cancer Alcohol consumption Research has shown that there was an association between drinking frequency and the volume of alcohol intake with liver diseases. To examine the association between alcohol consumption with liver cancer, the history of alcohol consumption, drinking frequency and the volume of alcohol intake of the subjects were analyzed. Of 465 the 40 liver cancer patients, there were 30 (75%) patients having the history of alcohol consumption. In comparison with the control groups, this can be concluded that alcohol drinkers would get 7 times greater risk of contracting liver cancer than non-drinkers (OR=7.0, p<0.01, χ 2 =16.24). In addition, alcohol can interrelate with hepatitis B in the pathogenesis of liver cancer 1 . The result of this study has demonstrated that there was a strong relation between the drinking frequency and liver cancer. Frequent drinkers have more 4.5 times at risk of liver cancer than non-frequent drinkers (OR=4.5, p<0.05, χ 2 =4.2). Frequently consuming alcohol can speed up the progress of the development of liver lesions to liver cancer. The structure and function of the liver can be recovered by ceasing to drink alcohol. However, if alcohol consumption has occurred over many years, it can lead to permanent lesions of the liver. Viral hepatitis often occurs in alcoholics. Both viral hepatitis and alcoholism can lead to cirrhosis which promotes the development of liver cancer. Regarding the volume of alcohol intake, research has shown that daily consuming 30 grammes of ethanol on average can lead to the high risk of cirrhosis . The results of this study pointed out that the subjects who drunk more than 30 gammes of alcohol daily had more 5.18 times at risk of liver cancer than the light drinking subjects (OR=5.18 với p<0.05 và χ 2 =5.18). Tobacco consumption Though toxic components of tobacco are transformed in the liver, little research has been done on the relationship between tobacco consumption and the liver’s lesions. In this study, patients with a history of tobacco consumption (accounted for 42.5%) had a 2.51 times higher risk of liver cancer than non-smokers (OR = 2.51, p < 0.05, χ 2 = 4.07). Exposure to chemicals In the world, there are 6,000 cases of cancer of all kinds due to pesticides annually. The halogenated organic pesticides is not a harmful carcinogen for the liver, but is a promoter stimulating unlimited liver cell proliferation which is believed to play an important role in the development of liver cancer. However, this study showed that the exposure to organic pesticides did not reveal a relationship to liver cancer (OR=1.48, p>0.05, χ 2 = 0.39). Familial history of liver cancer Several studies have mentioned familial history as an important factor of liver cancer. The results from table 11 shows that subjects who have relatives who contracted liver cancer get more than 5.52 times higher at risk of liver cancer than those who have not (OR = 5.52, p < 0.01, χ 2 = 5.16). Particularly, this happens more often among 466 patients having HBsAg(+). 5. Conclusion Overall, this research was useful in identifying risk factors of liver cancer. The results from this research will be used to inform the community and future study of the risk factors of liver cancer including HBsAg (+), history of alcohol consumption, drinking frequency, the volume of alcohol intake, tobacco consumption and familial history of liver cancer. Thereto, the exposure to organic pesticides is not associated with liver cancer. REFERENCES 1. Dominguez, MH., Gaytan, GS. Hepatocellular Carcinoma. Ultra structural Pathology, 25(6), (2001), 497-516. 2. Lee, JH., Oh, BK., Choi, J., Park, YN. Telomeric 3’ overhangs in chronic HBV-related hepatitis and hepatocellular carcinoma. International journal of cancer, 123, (2008), 264-272 3. Dinh Thanh Hue. Theory of origin and analytical study by observing. Epidemiological methods, (2004), 103-108. 4. Pham Van Linh, Pham Anh Vu, Duong Thi Hao. Research on the values of laboratory tests of diagnosing liver cancer. Vietnamese medical journal, 297, (2004), 152-157. 5. Brown, LM. Epidemiology of alcohol-associated cancers, Alcohol, 35(3), (2005), 161- 168. . Van Linh College of Medicine and Pharmacy, Hue University SUMMARY Research on the risk factors of liver cancer, particularly HBV infection is necessary for preventing liver cancer and to reduce. Objectives: To identify the risk factors among patients with liver cancer in Hue college of Medicine and Pharmacy. Methods: A case-control study was conducted from May 2007 to May 2008 in which there. interviewed. 2.5. Statistical analysis Classical analysis methods of case-control study was used to analyze data. OR value and χ 2 were calculated. In this study, the EPI INFO 6.04 was used for