Objective
To study the COVID-19 disease and vaccination status, and the causes of refusal of vaccination among survivors of medullary thyroid cancer.
Methods
From March to July 2022, and after the end of the 4 waves of COVID-19, we surveyed patients with medullary thyroid carcinoma (MTC) followed in the Endocrinology Department of the University Hospital of Constantine in Algeria. Survey measures include the status concerning COVID-19 disease, vaccination status, and the causes of vaccine refusal.
Results
From 27 patients with MTC, median age 52 years, 77.8 women, AJCC 8 stage I 33.3%, stage II 18.5%, stage III 7.4%, and stage IV 40.7%. Median duration evolution of 58 months, 11.5% have received radiotherapy and 19.2% were taking tyrosine kinase inhibitors. 46.2% had a recurrence/persistent disease among them 19.2% were M1. 19.2% had high blood pressure and 23.1% were diabetic. COVID-19 infections were reported by 46.2% of patients, and 32% were vaccinated (8% 1 dose, 16% 2 doses, 8% 3 doses). Answers about causes of refusal were fear of potential side effects in 44.4% of patients, fear of interaction with active treatment in 17%, previous COVID-19 infection in 5.9%, fear of allergic reaction in 5.9%, discouraged by a health professional in 5.9%, does not believe in vaccine effectiveness 5.9%, and fear of intramuscular injection 5.9%. No statistically significant differences between vaccinated and not vaccinated groups were found according to clinical characteristics were found.
Discussion/Conclusion
Despite being at high risk, most of our patients with medullary thyroid carcinoma are still not vaccinated mainly because of fear of vaccine side effects, more efforts have to be done to reinforce confidence in COVID-19 vaccination.