Saima N. Waqar, MD

Influenza infection is a potential cause of additional morbidity and mortality in patients who are immunocompromised because of cancer or its treatment. Of particular note, influenza infection may delay or interrupt chemotherapy and necessitate hospitalization. Successful immunization depends on an intact immune system that can produce antibodies in response to antigen exposure. Patients with cancer often have a suppressed immune system, resulting from their disease and/or immunosuppressive therapies, and as a consequence they may have a suboptimal serologic response to influenza vaccination. Since vaccination is the only proven method for preventing influenza infection, the Advisory Committee on Immunization Practices recommends seasonal influenza vaccination for adults without contraindications who have disease- or medication-related immunosuppression. Patients with cancer should be given the trivalent inactivated vaccine. Preliminary data suggest that administering the vaccine between cycles of chemotherapy may yield the best results.