This article is more than 5 years old. Information may no longer be current.
Flu vaccination shows modest efficacy among patients with cancer
Click Here to Manage Email Alerts
Patients with cancer and cancer survivors should receive seasonal influenza vaccination, although vaccination appeared somewhat less effective for patients with hematologic vs. solid tumor malignancies, according to results of a population-based study published in Journal of Clinical Oncology.
“Patients with cancer are at a high risk for mortality and morbidity from seasonal influenza ... [but] the benefits of influenza vaccination for [these patients] are uncertain,” Phillip S. Blanchette, MD, MSc, oncologist in the division of oncology and department of medicine at University of Toronto, and colleagues wrote. “Some reports have suggested clinical benefit from seasonal influenza vaccination, but most of these studies had small sample sizes and methodologic limitations.”
Blanchette and colleagues evaluated vaccine effectiveness against laboratory-confirmed influenza among patients with cancer using an observational test-negative study design.
Researchers identified 26,463 patients with cancer (mean age, 70 years; 52% men) who had been tested for influenza in Ontario, Canada, during the 2010-11 and 2015-16 influenza seasons. Mean time since cancer diagnosis was 6 years. Most of the patients (69%) had solid tumor cancers, and 23% received active chemotherapy.
Among all patients, 4,320 (16%) tested positive for influenza and 11,783 (45%) had received vaccination. Researchers calculated vaccine effectiveness by comparing the ratio of the odds of vaccination among test-positive inuenza cases with those of test-negative inuenza controls.
Results showed vaccine effectiveness against laboratory-confirmed influenza of 21% (95% CI, 15-26). Vaccine effectiveness against laboratory-confirmed influenza leading to hospitalization was 20% (95% CI, 13-26).
Vaccine effectiveness was greater for patients with solid malignancies vs. hematologic malignancies (25% vs. 8%; P = .015). Researchers also observed greater vaccine effectiveness against laboratory-confirmed influenza leading to hospitalization among patients aged 18 to 65 years vs. those older than 65 years (33% vs. 15%; P = .02).
Active chemotherapy did not significantly affect vaccine effectiveness, especially among patients with solid tumor malignancies.
A possible misclassification of vaccine status among patients not vaccinated in a physician’s office or clinic served as the study’s primary limitation.
“The development of improved vaccines and strategies to optimize influenza prevention among high-risk patients with cancer is warranted,” Blanchette and colleagues wrote. – by John DeRosier
Disclosures: Blanchette reports no relevant financial disclosures. Please see the study for all other authors’ relevant financial disclosures.
Read more about
Click Here to Manage Email Alerts