Direct-acting antivirals reduce liver cancer risk

There is a low risk of liver cancer after patients infected with hepatitis C virus (HCV) achieve sustained virological response (SVR) after treatment with direct-acting antivirals (DAA), according to a new study.

New DAAs have become widely used over the last few years and have changed the way physicians treat HCV.

“Almost everyone who is infected with HCV and treated with DAAs is now cured. There has been some concern of anecdotal reports that liver cancer may be a complication of this treatment, and that there is a risk of developing liver cancer that is more aggressive than previously seen with interferon-based treatment,” Fasiha Kanwal, MD, professor of medicine and interim chief of gastroenterology and hepatology at the Baylor College of Medicine in Houston, Texas, told Medical Economics.

Kanwal and colleagues conducted a retrospective cohort study of 22,500 HCV patients who were treated with DAAs in 129 Veterans Health Administration hospitals during 2015. They calculated the annual incidence rates for hepatocellular carcinoma (HCC) by SVR.

The researchers published their results on June 19, 2017, in Gastroenterology.

Next: Study details

Among those treated with DAA, 19,518 had SVR and 2,982 were without SVR. Their mean age was 61.6 years, and just more than one-third of them had cirrhosis.

There were 271 new cases of HCC, including 183 cases in patients with SVR.

Those who achieved SVR had a significantly reduced risk of HCC as compared to patients who did not achieve SVR. Some 40% of the patients in the study had established cirrhosis. Patients with established cirrhosis had the highest annual incidence of HCC after SVR, she noted.

Nearly half of HCC cases were classified as Stage I. Maximum size of the largest lesion was up to 5 cm in more than three-quarters of cases.

“DAAs were very effective, and cured most patients, with a much lower risk of liver cancer. DAAs appear to be protective. Those who are cured have a substantially lower risk of liver cancer,” said Kanwal.

She noted that the baseline risk of HCC is higher in this study compared to previous studies because patient characteristics have changed. “Treatments are so safe now that we are treating those we never thought of treating before, including those with significant liver disease and older patients, who have an increased baseline risk of liver cancer,” said Kanwal.

The study’s follow-up is short, only 15 months, she said, but “within that time frame there was a substantial reduction in liver cancer. With time and further follow-up, we will see if the risk falls farther,” said Kanwal.

The results clearly point to the value of successfully treating HCV-infected patients with DAAs, she added.

“Primary care physicians should not worry about the effects of DAAs on liver cancer. However, when patients with HCV are treated and they already have cirrhosis, they need to be followed up after DAA treatment. The overall risk of HCC is lower, but it remains high enough to carefully follow those patients with established cirrhosis,” Kanwal said.