Optimal timing ID'd for flu shot during three-week chemo cycle

(HealthDay)—For adults with solid cancer undergoing three-week cytotoxic chemotherapy cycles, antibody responses are comparable for influenza vaccination on day one and 11, according to a study published online Dec. 20 in Cancer.

Bhumsuk Keam, M.D., Ph.D., from Seoul National University College of Medicine in South Korea, and colleagues randomized adult patients with solid cancer undergoing scheduled three-week cytotoxic chemotherapy to receive the 2014 to 2015 seasonal influenza vaccine on day one (43 patients) or 11 (54 patients) during the chemotherapy cycle. Patients were stratified by age and previous influenza vaccination status. The final analysis included 83 patients.

The researchers found that the rates of seroprotection after vaccination were not significantly different for the day one versus day 11 groups (strain H1N1, 67 versus 75 percent [P = 0.403]; strain H3N2, 77 versus 80 percent [P = 0.772]; and strain B, 21 versus 27 percent [P = 0.472]). The groups also had similar seroconversion rates and post-vaccination geometric mean titers. The day 11 group more often had vaccine-related adverse events (32 versus 13 percent; P = 0.040).

"The antibody responses to influenza vaccination on days one and 11 during a three-week cytotoxic chemotherapy cycle were comparable," the authors write. "Influenza vaccination can be performed concurrently with cytotoxic chemotherapy or during the cytopenic period."