Can a patient undergoing radiotherapy for breast cancer receive a flu shot?

Influenza Vaccination for Breast Cancer Patients on Radiotherapy

Yes, patients undergoing radiotherapy for breast cancer should receive the influenza vaccination as it is safe, minimally invasive, and recommended for all cancer patients receiving active treatment. 1

Benefits and Safety

• Influenza vaccination is particularly important for cancer patients as they are considered a high-risk group with significant morbidity and mortality from influenza infections 1
• The Italian Society of Medical Oncology (AIOM) explicitly recommends influenza vaccination for cancer patients both untreated and receiving active therapy, including those undergoing radiotherapy 1
• Vaccination is safe for cancer patients and represents the most effective method for preventing influenza infection in this vulnerable population 1

Immune Response Considerations

• Cancer patients may experience disease- or treatment-related immunosuppression, potentially resulting in a suboptimal serologic response to influenza vaccination 1
• While the immune response may be reduced compared to healthy individuals, a considerable number of cancer patients still reach protective antibody levels 1
• Studies in breast cancer patients show that influenza vaccination is well-tolerated, though the immune response may be somewhat lessened in patients receiving certain treatments 2

Timing of Vaccination

• For patients undergoing radiotherapy for breast cancer, there are no specific contraindications to receiving the flu shot during treatment 1
• The optimal timing for administration of influenza vaccines in patients receiving cancer treatments is not clearly defined 1
• For patients with solid tumors, if possible, vaccination should be given mid-cycle of treatment or at the furthest possible time point away from treatment during a given cycle 1

Type of Vaccine

• Cancer patients should receive the trivalent inactivated vaccine rather than live attenuated influenza vaccine (LAIV) due to their potentially compromised immune system 1
• Some data suggest increased seroprotection rates with vaccines containing adjuvants, higher doses of antigen, or potentially a second dose of vaccine 1

Additional Protection Strategies

• Vaccination of household contacts and healthcare personnel is highly recommended to increase herd immunity in the patient's environment and reduce the likelihood of infection 1
• Strict preventive measures should be adopted in oncology wards when hospitalized patients develop influenza-like illness 1

Special Considerations for Breast Cancer Treatments

• Patients receiving targeted therapies like trastuzumab appear to benefit from influenza vaccination with good immunogenicity and without increased adverse events 3
• Patients on chemotherapy for breast cancer may mount better antibody responses when vaccinated early after a chemotherapy cycle (≤day 5) 4
• Patients receiving docetaxel may have lower immune responses to influenza vaccination, with seroconversion rates around 28% for H1N1, 8% for H3N2, and 16% for B strains 5

Common Pitfalls to Avoid

• Do not withhold vaccination due to concerns about efficacy; even a suboptimal response provides some protection and is better than no protection 1
• Do not administer live attenuated influenza vaccines to cancer patients due to their potentially compromised immune systems 1
• Do not assume that one vaccination strategy fits all cancer patients; response may vary based on specific treatments and individual factors 1

In summary, influenza vaccination is recommended for breast cancer patients undergoing radiotherapy as part of a comprehensive approach to reduce morbidity and mortality from influenza infection in this vulnerable population.