Is chronic hepatitis C virus infection a risk factor for breast cancer?

To evaluate the prevalence of breast tumors in adult females with chronic hepatitis C virus (HCV) infection.

Prospective, single-center study, based on female outpatients consulting in a liver unit, for 1 year. The study group included females with present and/or past history of chronic infection by HCV. Patients with spontaneous recovery were excluded. Chronic hepatitis had been proved by liver biopsy in the majority of cases and/or biological markers of inflammation and fibrosis. The control group included female patients with other well documented chronic liver diseases: chronic hepatitis B, alcoholic liver disease, autoimmune hepatitis, hemochromatosis, non alcoholic liver disease, chronic cholangitis. Participating patients were prospectively questioned during consultation about past breast history and follow-up by mammography.

Breast carcinoma was recorded in 17/294 patients with HCV infection (5.8%, 95% CI: 3.1-8.4) vs 5/107 control patients (4.7%, 95% CI: 0.67-8.67). Benign tumors of the breast (mastosis, nodules, cysts) were recorded in 75/294 patients with HCV infection (25.5%, 95% CI: 20.5-30.5) vs 21/107 (19.6%, 95% CI: 12.1-27.1) in the control group. No lesion was noted in 202 patients with HCV (68.7%, 95% CI: 63.4-74) vs 81 control patients (75.7%, 95% CI: 67.6-83.8). Despite a trend to an increased prevalence in the group with HCV infection, the difference was not significant compared to the control group (P = NS). In patients over 40 years, the results were, respectively, as follows: breast cancer associated with HCV: 17/266 patients (6.3%, 95% CI: 3.4-9.3) vs 5/95 patients (5.2%, 95% CI: 0.7-9.7) in the control group; benign breast tumors: 72/266 patients with HCV infection (27%, 95% CI: 21.7-32.4) vs 18/95 patients (18.9%, 95% CI: 11-26.8) in the control group; no breast lesion 177/266 (66.5%, 95% CI: 60.9-72.2) in patients with HCV infection vs 72/95 (75.7%, 95% CI: 67.1-84.4) in the control group. The differences were not significant (P = NS).

These results suggest that chronic HCV infection is not a strong promoter of breast carcinoma in adult females of any age.