{Reference Type}: Case Reports {Title}: Adrenal schwannoma can be FDG-Avid on PET/CT: case report and review of historic institutional pathology. {Author}: Fackelmayer OJ;Rodriguez ED;Sisk AE;Livhits MJ; {Journal}: Diagn Pathol {Volume}: 18 {Issue}: 1 {Year}: 2023 Oct 13 {Factor}: 3.196 {DOI}: 10.1186/s13000-023-01399-5 {Abstract}: Schwannomas are benign, generally indolent tumors of neural crest origin and comprise the most common histologic tumor of peripheral nerves. Schwannomas are a rare histology for retroperitoneal tumors and very rare histologic findings for tumors of the adrenal gland with fewer than 50 cases in the reported literature. Here we present a case report of a non-hormonally functional but metabolically active adrenal tumor with indeterminate imaging characteristics with final pathology showing a 6.1 cm adrenal schwannoma as well as historical institutional pathology review revealing two additional cases.