Palpable parathyroid adenomas presenting as clinical solitarythyroid nodules and cytologically as follicular thyroid neoplasms

Background: A palpable parathyroid mass, in a patient with primary hyperparathyroidism, is presumed to be parathyroid carcinoma until proven otherwise, with other less common causes including parathyroid cysts and adenomas. These parathyroid pathologies can be more difficult to interpret with concomitant thyroid disease. Methods: A retrospective review was undertaken of a series of three patients with palpable parathyroid adenomas mimicking thyroid nodules. Results: Two of three patients had preoperative biochemical evidence of primary hyperparathyroidism. Sestamibi scanning confirmed the presence of parathyroid pathology in one case. Fine-needle aspiration cytology revealed probable follicular neoplasms of the thyroid in all three cases. Only one of three parathyroid adenomas was diagnosed at neck exploration; the others were diagnosed at subsequent histopathology. Conclusion: Parathyroid and thyroid disease often occur simultaneously. Concomitant parathyroid pathology should be considered, even in the absence of biochemical and radiological evidence, at neck exploration for thyroid disease. Macroscopic identification of parathyroid disease at neck exploration can be difficult when within the thyroid gland capsule. Cytology and imaging of parathyroid adenomas may, on occasion, mimic follicular thyroid neoplasms.