COVID-19 Vaccine-Induced Radiation Recall Phenomenon

Int J Radiat Oncol Biol Phys. 2021 Jul 15;110(4):957-961. doi: 10.1016/j.ijrobp.2021.02.048. Epub 2021 Mar 4.


Radiation recall phenomenon (RRP) is an uncommon, late occurring, acute inflammatory skin reaction that emerges in localized areas coincident with previously irradiated radiation therapy (RT) treatment fields. RRP has been known to be triggered by a number of chemotherapy agents. To the best of our knowledge, this report is the first description of RRP after administration of the Pfizer-BioNTech vaccine for COVID-19, or any other currently available vaccine against COVID-19. Acute skin reactions were observed in 2 RT patients with differing timelines of RT and vaccinations. In both cases however, the RRP presented within days of the patient receiving the second dose of vaccine. For each RT course, the treatment planning dosimetry of the radiation fields was compared with the area of the observable RRP. RRP developed within the borders of treatment fields where prescription dose constraints were prioritized over skin sparing. Our observation is currently limited to 2 patients. The actual incidence of RRP in conjunction with Pfizer-BioNTech vaccine or any other vaccine against COVID-19 is unknown. For patients with cancer being treated with radiation with significant dose to skin, consideration should be given to the probability of RRP side effects from vaccinations against COVID-19.

Publication types

  • Case Reports

MeSH terms

  • Aged
  • BNT162 Vaccine
  • COVID-19 Vaccines / administration & dosage
  • COVID-19 Vaccines / adverse effects*
  • Humans
  • Immunization Schedule
  • Immunization, Secondary / adverse effects*
  • Lung Neoplasms / diagnostic imaging
  • Lung Neoplasms / radiotherapy*
  • Male
  • Middle Aged
  • Radiodermatitis / etiology*
  • Radiodermatitis / pathology
  • Radiosurgery / methods
  • Sarcoma / diagnostic imaging
  • Sarcoma / radiotherapy*
  • Skin Neoplasms / diagnostic imaging
  • Skin Neoplasms / radiotherapy*
  • Spinal Cord Compression / surgery
  • Thoracic Wall


  • COVID-19 Vaccines
  • BNT162 Vaccine