Herpes Zoster Following COVID-19 Vaccination in Long-Term Breast Cancer Survivors.

Mortality from coronavirus disease 2019 (COVID-19) is higher among patients with cancer. Vaccination represents a cornerstone in overcoming the disease, and vaccine safety needs to be closely assessed. This article discusses two cases of herpes zoster (HZ) following the administration of the BNT162b2 mRNA vaccine in patients who are long-term survivors of breast disease. HZ developed 24 days and two days after the second dose of the vaccine in women aged 81 and 61, respectively. These two patients were breast cancer operated respectively nine and 16 years before; interestingly HZ developed in the same site of previous surgical resection. The patients did not show lymphocytopenia or other signs of immunosuppression and were treated with acyclovir, resulting in the complete resolution of HZ. To our knowledge, these two patients are the first described cases of HZ reactivation following COVID-19 vaccination in cancer survivors.