COVID-19 Vaccine Considerations for Appendix Cancer and Pseudomyxoma Peritonei Patients

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COVID-19 Vaccine Considerations for Appendix Cancer and Pseudomyxoma Peritonei Patients

For more information regarding COVID-19 recommendations and resources for appendix cancer and pseudomyxoma peritonei patients go to our other pages: COVID-19 Patient Information and/or COVID-19 Resources


General considerations:

Two vaccines are currently being distributed in the United States through Emergency Use Authorization (EUA): the BNT162b2 (Pfizer) and mRNA-1273 (Moderna) mRNA COVID-19 vaccines. Both vaccines achieved 94-95% vaccine efficacy in the study population, however neither trial enrolled patients with immunocompromising conditions or medications1,2. Persons with stable HIV infection were included in mRNA COVID-19 vaccine clinical trials, though data remain limited. The main concerns for immunocompromised patients include safety and efficacy.



The most commonly observed side effects in immunocompetent study subjects include pain at the injection site, fever, headache, fatigue, and joint pain, more common with the second dose of vaccine. Theoretical concerns in immunocompromised patients include a hyper-inflammatory response. These effects have not been demonstrated in humans and protein-based and inactivated vaccines have not been associated with unique side effects in immunocompromised patients. Given current widespread community transmission of COVID-19, the benefits of vaccination likely outweigh safety concerns in the majority of patients.



Patients receiving cytotoxic chemotherapy may have diminished responses to the vaccine. However, immunocompromised patients are at high risk of morbidity and mortality associated with COVID-19 and vaccination has not been associated with major safety concerns. Given current widespread community transmission of COVID-19, the benefits of vaccination outweigh risks for the majority of patients undergoing cancer therapy. This recommendation is supported by the American Society of Hematology, American Society for Transplantation and Cellular Therapy, and European Society for Blood and Marrow Transplantation3,4.


Because immunocompromised individuals may not respond to the vaccine and because vaccine recipients who contract COVID-19 may shed infectious virus, it is critical that patients should continue social distancing, handwashing, and mask-wearing despite vaccination.


Vaccines authorized for use in the US:

Mechanism Dosing schedule
BNT162b2 (Pfizer) mRNA 2 doses, 21 days apart
mRNA-1273 (Moderna) mRNA 2 doses, 28 days apart


Patients undergoing cytotoxic chemotherapy:

Patients are anticipated to have the best response to vaccination when given ≥2 weeks before chemotherapy. If a 2 week window is not feasible, vaccination and immunosuppression should be spaced out as much as possible.

Among patients receiving cytotoxic chemotherapy for solid tumor malignancies, administer vaccine when it is available6

Specific guidance regarding biologic therapies and vaccine deferral:

    1. Rituximab, ofatumumab, obinatuzumab, blinatumomab, alemtuzumab: suggest deferral of vaccination for 6 months
    2. ATG: suggest deferral of vaccination for 3 months
    3. Daratumumab, TNF inhibitors: no deferral necessary

Checkpoint inhibitors: No contraindications to vaccination when available. Autoimmune and vaccine reactions may look similar.


Asplenic Patients

The CDC recommends  that groups at high risk for severe illness (including those with asplenia) may still receive the vaccine if there are no contraindications. Individuals lacking functional adaptive immune cells, such as those who are asplenic, may be unable to generate a fully protective immune response to the SARS-CoV-2 vaccine. It is possible that asplenic patients may have a weakened immune response when compared to the general population, and thus should be advised regarding the importance of maintaining all current guidance to protect themselves even after vaccination. Additionally, caregivers and household contacts should be strongly encouraged to get vaccinated when vaccine is available in an effort to protect the patient.7


Thank you to Dr. Laura Lambert and the Huntsman Cancer Institute for providing much of the information listed above.

  1. Polack FP, Thomas SJ, Kitchin N, et al. Safety and Efficacy of the BNT162b2 mRNA Covid-19 Vaccine. The New England journal of medicine. 2020;383(27):2603-2615.
  2. Baden LR, El Sahly HM, Essink B, et al. Efficacy and Safety of the mRNA-1273 SARS-CoV-2 Vaccine. The New England journal of medicine. 2020.
  3. Ljungman P, Cesaro S, Cordonnier C, Mikulska M, Styczynski J, de la Camara R. COVID-19 vaccines, Version 2.1 December 21, 2020. 2020.
  4. Auletta J, Chemaly RF, Khawaja F, et al. ASH-ASTCT COVID-19 and Vaccines: Frequently Asked Questions. 2020.
  5. Prevention CfDCa. Interim Clinical Considerations for Use of mRNA COVID-19 Vaccines Currently Authorized in the United States. Published 2021. Accessed.
  6. NCCN. Preliminary Recommendations of the NCCN COVID-19 Vaccination Advisory Committee. 2021.


Last updated 2/9/21