Cytological challenges in the diagnosis of intrathyroidal parathyroid carcinoma: A case report and review of literature

Abstract

Parathyroid carcinoma is an uncommon malignancy and the probability of an intrathyroidal location is low. Fine needle aspirations (FNA) of these presumably "thyroid nodules" can lead to misinterpretation because of the similarities in cytological features of parathyroid and thyroid lesions. Despite limitations, USG guided FNA cytology remains the first line of investigation. We report a case of intrathyroidal parathyroid carcinoma presenting with hypercalcemia and elevated serum parathormone. Cytological findings attributed it to a possible parathyroid lesion and histopathology revealed a parathyroid carcinoma. It is reported due to its rare occurrence on FNA along with brief literature review.

Keywords: fine needle aspiration cytology; hyperparathyroidism; parathyroid carcinoma.