Chronic hepatitis C infection as a risk factor for renal cell carcinoma.

BACKGROUND: Chronic hepatitis C virus (HCV) infection causes cirrhosis and hepatocellular carcinoma but is also etiologically linked to several extrahepatic medical conditions including renal disorders. HCV is also associated with extrahepatic malignancies and may be oncogenic. Whether HCV confers an increased risk of renal cell carcinoma (RCC) remains controversial.

AIMS: Prospectively determine whether chronic HCV is associated with an increased risk of RCC.

METHODS: At an integrated medical center in Detroit, Michigan, adult patients with suspected RCC or newly diagnosed colon cancer (controls) were screened for hepatitis C antibody (HCAB) and HCV RNA. Renal or colon cancers were confirmed histologically. The proportion of patients with HCAB and HCV RNA in each group was compared, and risk factors for renal cell carcinoma were determined by multivariable logistic regression analysis.

RESULTS: RCC patients had a higher rate of HCAB positivity (11/140, 8 %) than colon cancer patients (1/100, 1 %) (p < 0.01). Of the HCAB-positive patients, 9/11 RCC and 0/1 controls had detectable HCV RNA. HCV RNA positivity was a significant risk factor for RCC (OR 24.20; 95 % CL 2.4, >999.9; p = 0.043). Additionally, viremic RCC patients were significantly younger than RCC patients who were HCV RNA negative (p = 0.013).

CONCLUSIONS: Patients with chronic HCV are at heightened risk of RCC.