, according to a new report.
Among patients with cirrhosis and fibrosis-4 (FIB-4) scores of 3.25 or higher, the incidence of hepatocellular carcinoma appeared to decline progressively each year up to 7 years after a sustained virologic response, although the rate remained above the 1% per year threshold that warrants screening.
“The majority of patients with hepatitis C have been treated and cured in the United States,” George Ioannou, MD, the senior study author and professor of medicine at the University of Washington, Seattle, said in an interview. “After hepatitis C eradication, these patients generally do very well from the liver standpoint, but the one thing they have to continue worrying about is development of liver cancer.”
Dr. Ioannou, who is also director of hepatology at the Veterans Affairs Puget Sound Health Care System, Seattle, noted that patients may be screened “indefinitely,” which places a burden on the patients and the health care system.
“We are still not sure to what extent the risk of liver cancer declines after hepatitis C eradication as more and more time accrues,” he said. “In those who had cirrhosis of the liver prior to hepatitis C cure, we are still not certain if there is a time point after hepatitis C cure when we can tell a patient that their risk of liver cancer is now very low and we no longer need to keep screening for liver cancer.”
The study was published online in Gastroenterology.
Risk calculations
In a previous study, Dr. Ioannou and colleagues found that hepatocellular carcinoma risk declined during the first 4 years of follow-up after a sustained virologic response from direct-acting antiviral medications. But the follow-up time wasn’t long enough to determine whether the cancer risk continues to decline to levels low enough to forgo screening.
In this study, Dr. Ioannou and colleagues extended the follow-up to 7 years. They were curious to see whether the cancer risk declines enough to drop the screening requirement, particularly as related to pretreatment cirrhosis and fibrosis-4 scores.
The research team analyzed electronic health records from the Veterans Affairs Corporate Data Warehouse, a national repository of Veterans Health Administration records developed specifically for research purposes.
The researchers included 29,033 patients in the Veterans Affairs health care system who had been infected with hepatitis C virus and were treated with direct-acting antivirals between January 2013 and December 2015. The patients had a sustained virologic response, which is defined as a viral load below the lower limit of detection at least 12 weeks after therapy completion.
The patients were followed for incident hepatocellular carcinoma until December 2021. The researchers then calculated the annual incidence during each year of follow-up after treatment.
About 96.6% of patients were men, and 52.2% were non-Hispanic White persons. The average age was 61 years. The most common conditions were alcohol use disorder (43.7%), substance use disorder (37.7%), and diabetes (28.9%).
Among the 7,533 patients with pretreatment cirrhosis, 948 (12.6%) developed hepatocellular carcinoma during a mean follow-up period of 4.9 years. Among patients with FIB-4 scores of 3.25 or higher, the annual incidence decreased from 3.8% in the first year to 1.4% in the seventh year but remained substantial up to 7 years after sustained virologic response. Among patients with both cirrhosis and a high FIB-4 score, the annual rate ranged from 0.7% to 1.3% and didn’t change significantly over time.
Among the 21,500 patients without pretreatment cirrhosis, 541 (or 2.5%) developed hepatocellular carcinoma during a mean follow-up period of 5.4 years. The incidence rate was significantly higher for patients with high FIB-4 scores. Among patients without cirrhosis but who had a high FIB-4 score, the annual rate remained stable but substantial (from 0.8% to 1.3%) for up to 7 years.
In a subgroup analysis that examined incidence according to changes in FIB-4 scores before and after treatment, the rate remained high among those with cirrhosis regardless of a score change. Among those without cirrhosis but who had a persistently high FIB-4 score, the incidence was high. In those without cirrhosis whose FIB-4 score dropped, the incidence was lower.
“The study demonstrates a clear decline in the risk of liver cancer over time after hepatitis C cure in the highest-risk group. This is very positive news for patients,” Dr. Ioannou said. “However, even with that decline in risk up to 7 years after eradication of hepatitis C with direct-acting antivirals, the risk is still high enough to warrant liver cancer screening.”