HCV patients treated with DAA therapy not at increased risk of developing liver cancer, study finds

A new study presented this week at The Liver Meeting® — held by the American Association for the Study of Liver Diseases — found patients with hepatitis C who take direct-acting antiviral medication are at no higher risk for developing liver cancer than those who do not take the medication. However, they might be at an increased for more aggressive, infiltrative patterns of cancer, should they develop it.

"Data on clinical outcomes in cirrhotic patients with hepatitis C treated with direct-acting antiviral agents (DAAs) are still scanty and somehow controversial, and this is particularly true for development of a liver cancer, one of the most frequent and deadly complications of the disease," says Alfredo Alberti; professor of gastroenterology at University of Padova in Padova, Italy, and lead investigator in the study.

Recent studies have suggested the possibility of increased risk of developing liver cancer (hepatocellular carcinoma, or HCC) during and after DAA treatment in patients with hepatitis C (HCV). Dr. Alberti's team recently looked at the incidence of new cases of liver cancer among 3,075 HCV patients with advanced liver disease who were treated with DAAs. Almost 70 percent of the patients studied were men, and nearly 86 percent had cirrhosis (scarring of the liver). HCV genotypes one through four were all represented in the study, and patients with a past history of liver cancer were excluded.

All participants were treated with oral DAA therapy and monitored monthly. At the time of Dr. Alberti's team's analysis, patients had an average follow up of nearly 305 days from the time they started DAA therapy. During this period, the researchers found 41 patients had developed liver cancer, and the overall incidence (per 100 patient years) was 1.64.

Dr. Alberti's team further noted an incidence rate of 0.23 in patients without cirrhosis and of 1.93 in those with cirrhosis (1.93 for men and 1.94 for women). Incidence rates varied among HCV genotypes as well, with HCV-1 at the low end (1.70) and HCV-3 at the high end (2.44). Finally, cirrhotic patients with a Child-Pugh score of 'A' had an incidence rate of 1.64 and those with more advanced disease and a score of 'B' had a rate of 2.92.

"These rate incidences were not significantly different from those observed in historical control cohorts of similar patients from the same geographic area, not receiving antiviral therapy, indicating that the risk of developing HCC is not increased by oral DAAs, being closely dependent on stage of disease as in untreated cases," says Dr. Alberti.

Liver cancer was diagnosed four weeks after starting DAA therapy in three patients, at week eight in three patients, week 12 in six patients, between week 12 and 24 in thirteen patients, and after treatment ended in sixteen patients. Fifty percent of patients who developed liver cancer developed a single nodular cancer with a typical vascular pattern, while 50 percent had a more aggressive pattern. Finally, 28 out of the 41 patients who developed cancer were successfully cured of HCV (reaching a sustained virological response at 12 weeks), while the remaining 13 relapsed.

In different analyses of the data, Dr. Alberti's team found elevated liver enzymes and low platelet count to be associated with liver cancer risk, while gender, age, HCV genotype and DAA regimen were not. The best baseline predictor of liver cancer risk was APRI scores (which calculate scarring in the liver). The researchers find the risk of developing liver cancer increased linearly by 10 percent at each one-point increase in APRI value.

"The results of this study, while confirming that DAAs treatment doesn't increase the overall risk of HCC, indicate that there is no pharmacological prevention of HCC even with successful antiviral therapy, at least during the first six to 12 months after initiation of treatment when microscopic and therefore initially invisible HCC foci might even be boosted in their growth as consequence of the profound immunological and molecular changes in the liver microenvironment following abrupt cessation of HCV replication," explains Dr. Alberti. "Therefore, it is mandatory that patients treated with DAAs with advanced liver disease should continue to be monitored for HCC."