Kidney Cancer Linked to Hepatitis C Virus
Chronic infection with hepatitis C virus (HCV) increases a person's risk for renal cell carcinoma (RCC), a study found.
Detroit investigators led by Stuart C. Gordon, MD, Clinical Professor of Medicine at Wayne State University School of Medicine, studied 67,063 individual tested for HCV between 1997 and 2006 at Henry Ford Hospital and who were followed up for the development of RCC until April 2008.
Of these subjects, 3,047 (4.6%) were HCV positive. RCC was diagnosed in 17 (0.6%) of these subjects compared with 177 (0.3%) of the 64,006 HCV-negative individuals. HCV-infected patients had a 77% increased risk of RCC than HCV-negative subjects, after adjusting for known risk factors African-American race, make gender, and CKD, according to a report in Cancer Epidemiology, Biomarkers & Prevention (2010;19:1066-1973).
“The results of this study would suggest a more careful surveillance of newly diagnosed RCCs for the presence of HCV infection,” Dr. Gordon and his colleagues concluded.
“It is premature to recommend more comprehensive screening of HCV-positive patients for this relatively uncommon neoplasm. However, a heightened awareness of an increased kidney cancer risk should dictate more careful follow-up of incidental renal defects when detected on imaging procedures in patients with chronic hepatitis C.”
Of the 17 RCC cases in HCV-positive patients, eight were clear cell, six were papillary, and two were mixed clear cell and papillary. One was classified as undifferentiated/other.
The average of age of HCV-positive patients with RCC was significantly younger than that of HCV-negative patients with RCC (54 vs. 63 years), a cancer generally found among older individuals, according to the researchers.
The authors noted that their findings validate previously published reports suggesting that older age and African-American race are independent risk factors for RCC. In multivariate analysis, each one-year increment in age was associated with a 3% increased risk of RCC. African-American race was associated with a 40% increased risk.
In addition, male gender and CKD were associated with a 2.4-fold and 4.4-fold increased risk, respectively.
Dr. Gordon's group said one of the strengths of their study was that it included a large, ethnically diverse, and well-defined cohort of subjects with ongoing contact with an integrated health-care system and serologic and virologic documentation of HCV infection status.
Potential study limitations included a lack of systematic tobacco histories and possible referral bias, which is inherent in a hepatologic and urologic tertiary medical center, the researchers stated.