Abstract
BACKGROUND: Primary pericardial mesothelioma is an extremely rare disease. Prognosis is poor, with little effects of chemo- or radio-therapy. The majority of cases is diagnosed at autopsy. CASE SUMMARY: A 22-year-old man, who presented with recurrent pericarditis and large pericardial effusion 2 months after a second BNT162b2 COVID-19 vaccine, underwent pericardiocentesis and pericardial window. Pathology specimen of pericardium revealed benign mesothelial inflammation, consistent with acute pericarditis. Four months later, he presented with a large pericardial mass manifesting in heart failure and underwent urgent pericardiectomy. A new pathology specimen immunostaining and fluorescence in situ hybridization analysis revealed pericardial mesothelioma. Despite intensive care, the patient died 3 weeks later. DISCUSSION: Primary pericardial mesothelial should be considered in the differential diagnosis of refractory recurrent pericarditis, even with prior biopsy-proven pericarditis or when a putative trigger (COVID-19 mRNA prior vaccination) is suspected, as was the case in this patient. Tumour diagnosis and identification consist of multimodal imaging and laboratory tests. A multidisciplinary, individualized care approach should be performed.