In addition to increasing the risk of hepatocellular carcinoma, researchers have found that hepatitis C virus infection is associated with an elevated risk for developing bile duct cancers and diffuse large B-cell lymphoma among US older persons, a study published in the journal Cancer has shown.1

Although previous research has established that hepatitis C virus infection causes hepatocellular carcinoma and subtypes of non-Hodgkin lymphoma, its associations with other malignancies is unknown.

To evaluate associations between hepatitis C virus infection and other cancers in the US older population, investigators analyzed Surveillance, Epidemiology, and End Results (SEER)-Medicare data from 1,623,538 adult patients aged 66 years or older who had their first cancer identified in SEER registries between 1993 and 2011 and from 200,000 cancer-free matched controls.

Results showed that 0.7% of patients infected with the hepatitis C virus developed a cancer vs 0.5% of controls.

After adjusting for confounding factors, researchers found that hepatitis C virus infection was associated with an approximately 31 times higher risk for developing cancers of the liver (odds ratio [OR], 31.5; 95% CI, 29.0-34.3), a 3 times higher risk of intrahepatic bile duct cancer (OR, 3.40; 95% CI, 2.52-4.58), and an approximately 2 times increased risk of extrahepatic bile duct cancer (OR, 1.90; 95% CI, 1.41-2.57).

The study further demonstrated that hepatitis C virus infection was associated with a 97% increased risk of anal cancer (OR, 1.97; 95% CI, 1.42-2.73) and a 53% higher risk of nonmelanoma nonepithelial skin cancer (OR, 1.53; 95% CI, 1.15-2.04), including Merkel cell carcinoma (OR, 1.92; 95% CI, 1.30-2.85) and appendageal skin cancers (OR, 2.02; 95% CI, 1.29-3.16).

Investigators also observed higher risks of hematologic malignancies, such as myelodysplastic syndrome (OR, 1.56; 95% CI, 1.33-1.83) and diffuse large B-cell lymphoma (OR, 1.57; 95% CI, 1.34-1.84), among patients infected with hepatitis C virus.

In contrast, the study revealed inverse association between hepatitis C virus infection and risk of uterine cancer (OR, 0.64; 95% CI, 0.51-0.80) and prostate cancer (OR, 0.73; 95% CI, 0.66-0.82).

Given the associations between hepatitis C virus infection and a variety of cancers, these findings ultimately support a possible etiologic role for the viral infection in an expanded group of malignancies.

Reference

1. Mahale P, Torres HA, Kramer JR, et al. Hepatitis C virus infection and the risk of cancer among elderly US adults: A registry-based case-control study. Cancer. 2017 Jan 24. doi: 10.1002/cncr.30559. [Epub ahead of print]