Gastrointestinal (GI) tumors are a significant burden of tumors in China. Similarly, China is also a major country with a high burden of hepatitis B. The role of hepatitis B as a causative factor for liver cancer is relatively clear. However, the relationship between hepatitis B virus infection and gastrointestinal (GI) tumors remains unclear. Therefore, Chinese scholars conducted a related study to explore the relationship between chronic hepatitis B virus (HBV) infection and the risk of gastrointestinal (GI) tumors (including liver, stomach, gallbladder cancer or extrahepatic bile duct cancer, pancreatic cancer, small intestine, esophageal cancer, and colorectal cancer). The results were published in the International Journal of Cancer.

Among the 93,402 participants, the average age was 51.52 ± 12.43 years, with 74,637 males (79.91%) and 18,765 females (20.09%). There were differences between the HBsAg seropositive group and the HBsAg seronegative group in terms of age, gender, TG, TC, ALT, TBil, hs-CRP, prevalence of hypertension, physical exercise, smoking status, family income, liver cirrhosis, fatty liver, gallstones, and gallbladder polyps (P > 0.05). There were no differences between the HBsAg seronegative group and the HBsAg seropositive group in BMI, prevalence of diabetes, alcohol consumption, cancer family history, marital status, high salt intake, and high school graduation status (including the above).

After a mean follow-up of 13.02 (12.68-13.20) years, 1,791 participants were diagnosed with gastrointestinal tumors (colorectal cancer (n = 664), liver cancer (n = 411), gastric cancer (n = 356), pancreatic cancer (n = 167), bladder or extrahepatic bile duct cancer (n = 155), esophageal cancer (n = 127), and small intestine cancer (n = 9)), including 99 cases (5.53%) diagnosed with multiple tumors. The crude incidence density of GI cancer per 1000 person-years was 1.57, 1.40, and 7.23 in the overall population, HBsAg seronegative group, and HBsAg seropositive group, respectively. Compared with HBsAg seronegative participants, a significant positive correlation between HBV infection and the occurrence of digestive system tumors was observed in both univariate models (risk ratio 5.14, 95% CI: 4.46-5.92) and multivariate adjusted models (risk ratio 5.59, 95% CI: 4.84-6.45).

In the specific analysis of different sites, after adjusting for potential confounding factors, participants with seropositive HBsAg had significantly increased risks of liver cancer (HR = 21.56, 95% CI: 17.32-26.85), gallbladder cancer or extrahepatic bile duct cancer (HR = 14.89, 95% CI: 10.36-21.41), colorectal cancer (HR = 1.75, 95% CI: 1.15-2.96), and pancreatic cancer (HR = 1.86, 95% CI: 1.10-3.99). However, there was no significant correlation between HBV infection and the risk of esophageal cancer, gastric cancer, or small intestine cancer.

In competing risk analysis, 9,535 participants died before the occurrence of gastrointestinal cancer during a median follow-up of 13 years. After adjusting for death as a competing risk event and confounding factors, the association between hepatitis B virus infection and the risk of developing liver, gallbladder, extrahepatic bile duct, colorectal, and pancreatic cancer was observed in both the CS model and the SD model.

Stratified analyses were conducted by age, gender, BMI, smoking, and drinking status. In all stratified analyses, HBV-infected patients were associated with an increased risk of liver cancer. Smoking and drinking status also influenced this association. A positive correlation between HBV infection and gallbladder or extrahepatic bile duct cancer was also observed in all stratified analyses. In the colorectal cancer analysis, a significant association was observed only in men, young adults, middle-aged adults, those with normal BMI, smokers, or non-drinkers, but no significant association was observed in women, elderly individuals, overweight, obese, non-smokers, or current drinkers. No interaction effects were found in any of the analyses. In the pancreatic cancer analysis, a significant association was found only in men, young adults, middle-aged adults, obese individuals, and non-smokers, and the interactions between them did not appear to be significant.

Overall, the study suggests that HBV infection is associated with an increased risk of liver and extrahepatic tumors, including gallbladder cancer, extrahepatic bile duct cancer, pancreatic cancer, and colorectal cancer, among adults in northern China.

Original source:

Liu T， Song C， Zhang Y， Siyin ST， Zhang Q， Song M， Cao L， Shi H. Hepatitis B virus infection and the risk of gastrointestinal cancers among Chinese population： A prospective cohort study. Int J Cancer. 2021 Dec 2. doi： 10.1002/ijc.33891. Epub ahead of print. PMID： 34855203.

Liu T, Song C, Zhang Y, Siyin ST, Zhang Q, Song M, Cao L, Shi H. Hepatitis B virus infection and the risk of gastrointestinal cancers among Chinese population: A prospective cohort study. Int J Cancer. 2021 Dec 2. doi: 10.1002/ijc.33891. Epub ahead of print. PMID: 34855203.