Sixteen years of data showed that daily aspirin therapy reduced the risk of HBV-related HCC by 29%, reported lead author, of Taichung (Taiwan) Veterans General Hospital and his colleagues. Analysis also showed that antiviral nucleos(t)ide analogue therapy and statin use were independently associated with reduced risk of HCC, whereas older age, cirrhosis, and male sex increased risk.
“Therapy with [nucleos(t)ide analogues] is associated with reductions in HCC risk, but the risk is not erased,” the investigators wrote in. “Therefore, using only [nucleos(t)ide analogue] therapy may not be enough for HCC prevention. Antiviral therapy is not indicated in most HBV carriers, so another effective way of reducing HCC risk needs to be developed.”
Previous studies have shown that aspirin can reduce the risk of colorectal cancer; however, data supporting aspirin for HCC prevention are limited to a few animal models and human studies, the latter of which are statistically unreliable.
“Therefore, we conducted a nationwide cohort study to evaluate the association of daily aspirin therapy with HBV-related HCC,” the investigators wrote.
They screened 204,507 patients with HBV included in the Taiwanese National Health Insurance Research Database (NHIRD) between 1997 and 2012, first excluding any with confounding conditions, such as hepatitis C infection or alcoholic liver disease. Next, 2,123 patients were identified who had taken aspirin for 90 days or longer. Finally, these cases were randomly matched with 8,492 control patients with HBV who had never received antiplatelet therapy. The main measured outcome was diagnosis with HCC. Patients were followed until this diagnosis was made, death occurred, or the end of the study period.
Analysis showed that most patients were male (72.4%) and took aspirin for about 4 years, usually prescribed for cardiovascular disease risk factors. Almost all patients in the treatment group (98%) received an aspirin dose of 100 mg or less.
After 5 years, the cumulative incidence of HCC in the aspirin group was 5.20% versus 7.87% in the control group (P less than .001). Multivariable analysis revealed that daily aspirin was associated with a significant risk reduction of 29% (HR 0.71; P less than .001), as were nucleos(t)ide analogues and statins, which lowered risk by 46% and 38%, respectively. In contrast, risk increased with older age at the rate of 1% per year, male sex carried an additional risk of 75%, and liver cirrhosis was associated with a 2.89-fold risk increase.
“In the present study, we report that daily aspirin therapy was associated with a reduced incidence of HCC in patients with [chronic hepatitis B],” the investigators wrote. “Our findings may be of help in future efforts to further improve the chemoprevention of HBV-related HCC, and a proof-of-concept study is thus warranted.”
The investigators described several mechanisms that may have contribute to the possible risk reduction provided by aspirin. For one, aspirin inhibits platelet activation, which is associated with development of HBV-related liver disease. Additional benefit may come from induction of HCC cell apoptosis, control of tumor growth, reduced liver fibrosis, and increased liver regeneration, all of which have been associated with aspirin in rodent models.
“Hepatitis B virus–related HCC is generally a consequence of chronic inflammation due to hepatitis, fibrosis, dysplasia, and tumor growth,” the investigators wrote, suggesting that aspirin-related reductions in inflammation could also explain reduced neoplastic activity.
To assess for increased risk of peptic ulcers secondary to aspirin, the investigators performed a subanalysis of peptic ulcer bleeding. These results showed that rates of peptic ulcer bleeding, at around 5%-6%, were similar between the aspirin group and the control group. Among other variables, cirrhosis didn’t significantly affect rates of peptic ulcer bleeding, and aspirin users had similar rates of peptic ulcer bleeding regardless of HBV status. Because of the study design, however, the investigators cautioned that these analyses could underestimate ulcer risk because patients who could not tolerate aspirin for at least 90 days were excluded from the study.
Although statins stood out as another possible risk reducer, the investigators noted that “randomized clinical trials are required to confirm the chemopreventive effect of statins.”
Similarly, the investigators suggested that a prospective trial is needed before aspirin can be adopted as an HCC preventive.
The study was funded by the Ministry of Science and Technology, National Health Research Institutes, and Taichung (Taiwan) Veterans General Hospital, Taiwan. One author reported financial compensation from Gilead and Bristol-Myers Squibb.
SOURCE: Lee T-Y et al. JAMA Intern Med. 2019 Mar 18. .