Vaccination considerations for patients receiving cancer therapy

Vaccination rates in patients with cancer remain low, yet these individuals are at increased risk of severe outcomes from vaccine-preventable illnesses.¹ Primary care providers are often uncertain about the safety of vaccines in this population and vaccine recommendations for these patients.^2,3 This article reviews vaccination in patients who are receiving cancer treatment, including safety, timing, and optimization of response to vaccination. Hematopoietic stem cell transplant, chimeric antigen receptor T-cell therapy, and travel vaccinations are outside the scope of this article.

Vaccines can be categorized broadly as live and non-live.^4,5 Live vaccines are attenuated and must replicate within the host to create an immune response (Table 1).^6-11 Live vaccines are contraindicated in immunosuppressed patients.^6,7,12 Non-live vaccines include inactivated, toxoid, subunit, conjugate, mRNA, and viral vector vaccines. Non-live vaccines can be administered to patients receiving cancer therapies; however, immunosuppression may diminish immune response, so consideration of a patient’s treatment schedule is important to optimize response to vaccination.⁸ Even with suboptimal response, there is minimal risk with non-live vaccines and the possibility of some benefit. Primary care providers should also consider vaccination of patients’ family members and close contacts to further protect patients receiving cancer treatment.¹³

Table 1.

Vaccine safety and administration considerations: Clear sections indicate unsafe vaccination circumstances for immunosuppressed patients while shaded sections indicate safe vaccination circumstances in this population.

Cancer therapies are diverse and include corticosteroids, endocrine therapy, radiation therapy, chemotherapy, targeted therapies, and immunotherapies. Immunosuppression will vary with each of these treatment types and, as such, recommendations regarding vaccination will vary according to treatment. Specific considerations for differing cancer therapies are reviewed in Table 2.^4-6,14-22 Ideally, patients should receive any outstanding immunizations before initiating cancer therapy; however, many patients may require time-sensitive vaccines such as those for influenza or COVID-19 while concurrently receiving therapy.^15,16 Patients are no longer considered immunosuppressed 3 months after cessation of treatment for cancer.⁶

Table 2.

Cancer therapies and implications for vaccination

CANCER THERAPY	CONSIDERATIONS FOR VACCINATION
Corticosteroids	Immunosuppressive dose of steroids: prednisone equivalent of ≥2 mg/kg/d or ≥20 mg/d if weight >10 kg, for ≥14 days
Endocrine therapy	No impact on vaccination No considerations for timing of vaccination
Radiotherapy	Radiation can cause immunosuppression when radiation fields encompass substantial bone marrow, such as the pelvis or craniospinal axis Immunosuppression is dose dependent and more likely to be seen in the setting of curative radiation treatment Clinically significant immunosuppression can be seen in the treatment of prostate, cervical, and anal cancers
Chemotherapy	The nadir for leukocytes generally occurs 7 to 14 d after each treatment. If a vaccine is given during a leukopenic period, there will be an inadequate immune response If immunization is necessary while receiving chemotherapy, give immediately before next cycle of treatment to allow for optimal immune system recovery and vaccine response
Targeted therapy	Some targeted agents (eg, sunitinib, palbociclib) can cause immunosuppression with leukopenia or decreased humoral immunity If patient is receiving a targeted therapy that causes immunosuppression, the timing of vaccination should be adjusted accordingly If patient is receiving anti-B-cell therapy (eg, rituximab), vaccinate at least 4 wk before therapy or a minimum of 6 mo after cessation of treatment
Immunotherapy	Live vaccines are not recommended in patients receiving immunotherapy as safety data are inadequate at this time Non-live vaccines are safe in patients receiving immunotherapy Vaccination has not been shown to increase the incidence of immune-mediated adverse effects

Data from the Advisory Committee on Immunization Practices,⁴ Pollard and Bijker,⁵ the Government of Canada,⁶ Ariza-Heredia and Chemaly,¹⁴ Hwang et al,¹⁵ Waissengrin et al,¹⁶ Keam et al,¹⁷ Groeneveld et al,¹⁸ Desage et al,¹⁹ Spagnolo et al,²⁰ Chen et al,²¹ Hoffmann et al.²²

Conclusion

This concise article is intended to provide practical support for primary care providers when vaccinating their patients who have been diagnosed with cancer. The recommendations in this brief will increase primary care providers’ familiarity with administration of vaccines in patients receiving cancer therapy, ideally enabling improved uptake and prevention of severe illness in this population.