Hepatitis C virus genotype distribution varies by underlying disease status among patients in the same geographic...

Hepatitis C virus (HCV) is a known carcinogen with considerable genetic heterogeneity: six different genotypes have been identified. HCV genotype distribution varies from country to country. In the United States, the most prevalent genotypes are 1a, and 1b followed by genotypes 2, and 3.

To examine whether the distribution of HCV genotypes differed by cancer status among patients in the same area.

We reviewed epidemiologic and virological data of 636 patients with HCV infection evaluated at 3 institutions in Houston, Texas, in 2008 and 2009.

We included 129 cancer patients (53 with hematologic malignancies and 76 with solid tumors), 333 immunocompetent patients, and 102 HIV-co-infected patients. The prevalence of genotype 1 (G-1) was 66% among cancer patients, 84% among immunocompetents (P=0.00004), and 99% among HIV-co-infected patients (P<0.00001). G-2 and G-3 were more common in cancer patients than other patients. Demographics, risk factors, and duration of HCV infection were similar between cancer and immunocompetent patients. G-1 was more prevalent in immunocompetents (84%) than in patients with hepatocellular carcinoma (74%, P=0.08) or lymphoma (59%, P=0.001). G-2 was more prevalent in lymphoma patients (24%) than in immunocompetents (8%, P=0.003); cancer risk was 3 times as great with G-2 as with other genotypes (OR 3.72, 95% CI 1.38-9.76).

This multicenter retrospective study provides evidence of differences in HCV genotype distribution by underlying disease among geographically related patients and suggests a possible greater carcinogenic potential of some variants. Large-scale prospective studies are warranted to investigate HCV genotype distribution in other regions.