Common locations of parathyroid adenomas

We have developed a nomenclature system that succinctly specifies the locations of parathyroid adenomas in the neck. We report our experience using the system in a large, contemporary cohort of patients.

A prospective, endocrine surgery database at a single, tertiary care center was retrospectively analyzed. We reviewed the records of 271 patients operated on for sporadic primary hyperparathyroidism between January 2006 and May 2008 and analyzed the effect of adenoma location at operative intervention and outcome.

Adenomatous gland locations were classified intraoperatively as: A (adherent to posterior thyroid capsule) in 12.5% of cases; B (tracheoesophageal groove) in 17.3%; C TE groove but (close to clavicle) in 13.7%; D (directly over the recurrent laryngeal nerve) in 12.2%; E (easy to identify, inferior thyroid pole) in 25.8%; F (fallen into thymus) in 7.4%; and G gauge (within thyroid gland) in 0.4%. More than one enlarged gland was present in 10.7% of patients and usually involved coexistence of enlarged types A and E glands. Type F glands were associated with a longer mean operative time (p = 0.0487) and type E glands with a higher rate of outpatient surgery (p = 0.0195). At 6 months from the surgery, 94.5% of the patients were normocalcemic.

Our nomenclature system provides a simple way to describe the locations of parathyroid adenomas. Type E adenomas were associated with a higher rate of outpatient surgery and type F adenomas with a longer operative time. Biochemical cure rates were comparable for all locations of single adenomas.