A 35-year-old man undergoes parathyroidectomy for primary hyperparathyroidism. Intraoperatively, a single enlarged gland is found and removed. Final pathology shows a parathyroid carcinoma. Which intraoperative finding most strongly suggests carcinoma rather than adenoma?

• A Gland weight greater than 1 gram
• B Oxyphil cell predominance
• C Presence of a rim of normal parathyroid tissue
• D Dense fibrosis and adherence to surrounding structures ✓

Explanation

Parathyroid carcinoma is suggested intraoperatively by dense fibrosis, capsular invasion, and adherence to surrounding structures such as the thyroid or strap muscles. A rim of normal tissue is characteristic of adenoma. Gland weight and oxyphil predominance are not reliable distinguishing features. Definitive diagnosis requires histopathological evidence of invasion.

Reference: Robbins and Cotran Pathologic Basis of Disease, 10th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

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