PT  - JOURNAL ARTICLE
AU  - Suha Abdulla
AU  - Eamon Shamil
AU  - Mark Wilsher
AU  - Antony Jacob
TI  - Atypical presentation of oncocytic parathyroid adenoma masquerading as metastatic carcinoma
AID  - 10.1136/bcr-2019-231373
DP  - 2019 Sep 01
TA  - BMJ Case Reports
PG  - e231373
VI  - 12
IP  - 9
4099  - http://casereports.bmj.com/content/12/9/e231373.short
4100  - http://casereports.bmj.com/content/12/9/e231373.full
SO  - BMJ Case Reports2019 Sep 01; 12
AB  - Parathyroid carcinoma is the rarest endocrine malignancy. Definitive diagnosis is challenging as it is difficult to distinguish malignant from benign disease. A 71-year-old man presented with weight loss and hypercalcaemia. CT scans revealed multiple lung nodules and lytic bone lesions that were consistent with metastatic dissemination. Technetium-99m-sestamibi-single-photon emission computed tomography scan showed an abnormal uptake in the right thyroid lobe. Fine-needle aspiration (FNA) was performed on three occasions. The patient underwent parathyroidectomy with ipsilateral hemithyroidectomy without postoperative complications. Microscopic examination showed a parathyroid neoplasm with fibrosis and intravascular tumour on a background of unremarkable thyroid parenchyma. This resulted in an initial impression of parathyroid carcinoma. Further review by two independent pathologists provided a final diagnosis of oncocytic parathyroid adenoma. This case highlights the subjectivity and interobserver variation with endocrine histological examination. FNA can induce changes that mimic parathyroid carcinoma on histology. An index of suspicion for benign parathyroid adenomas should be maintained.