Primary intrathyroidal paraganglioma: A case report of immunohistochemistry findings and a recommendation for surgical resection

Abstract

Introduction: Thyroid paragangliomas are very rare tumors. Awareness of its presentation is important to differentiate it from other common thyroid neoplasms. We present a care report of a primary intrathyroidal paraganglioma and its histopathologic findings. Case Report: A 58-year-old asymptomatic female was referred to the General Surgery clinic following an incidental finding of thyroid nodules on imaging. She had no significant personal or family history of thyroid disease. Routine blood and thyroid function studies were within normal limits. Neck ultrasound demonstrated a multinodular goiter with a hypoechoic nodule in the right superior thyroid. Fine needle aspirate (FNA) showed atypia of unknown significance (Bethesda 3). She underwent a right hemithyroidectomy which confirmed on pathological examination to be a 19 mm intrathyroidal paraganglioma, which was positive for neuroendocrine markers and negative for calcitonin and cytokeratin. Serum metanephrine studies returned within normal limits. Conclusion: Given the difference in management of paragangliomas compared to its cytology mimics and association with familial cancer syndromes, awareness of this rare tumor, and use of immunohistochemical stains are critical in arriving at the diagnosis, which has implications for clinical management and surveillance of these patients.