Treated hepatitis C virus (HCV) infections do not return after patients receive chemotherapy or immunosuppressive therapy, researchers report in the June issue of Clinical Gastroenterology and Hepatology.
Cancer chemotherapy leads to HCV reactivation in patients with chronic infections, but little is known about the effect of chemotherapy on HCV infections that have been cured among patients with sustained viral responses (SVRs). Immunosuppressive therapies could also reverse SVRs.
Parag Mahale et al. investigated whether cancer treatments led to relapse of HCV infection among 30 patients who achieved SVRs before they were diagnosed with and treated for cancer.
Half of the patients studied had hematologic malignancies and half had solid tumors; 60% had received HCV therapy with interferon and ribavirin. Chemotherapy was started at a median of 72 months after patients achieved their SVRs, and included rituximab (27%), cyclophosphamide (23%), cisplatin (17%), or corticosteroids (37%). The authors defined HCV infection relapse based on detection of HCV RNA in serum using commercially available assays.
Mahale et al. found that none of the patients had viral relapse after any form of cancer therapy. The authors conclude that SVRs are not affected by chemo- or immunosuppressive therapies.
Some studies have reported detection of HCV RNA in liver cells and peripheral blood mononuclear cells (PBMCs) from patients who already achieved SVRs, but little is known about the clinical significance of these observations. Mahale et al. were not able to determine whether PBMCs from patients included in their study hid some residual HCV.
Further studies are therefore needed to evaluate larger groups of patients, treated with other types of HCV therapies, to determine if these findings can be generalized to all cancer patients with a history of successfully treated HCV infection.