Endocrine Abstracts

Background: Often parathyroid indicentalomas (PI) in the form macroscopically enlarged single or multiple parathyroid glands are encountered during surgical thyroidectomy. The reported incidence in literature is variable (0.4–4.5%), but we feel its underreported compared to its frequency, as only less than 500 cases were reported thus far. Another enigma about PI is their clinical significance and natural history. In this context, we analysed our own experience and tried to derive lessons on its clinical relevance.

Methods: This is a retrospective study conducted in Endocrine Surgery department of tertiary care Hospital. All surgical thyroidectomies were performed by single primary endocrine surgeon. Study spanned over 10 years from 2009 to 2018. In all 2105 cases of thyroidectomies with no preoperative diagnosis of hyperparathyroidism are included in this study. A retrospective analysis was performed to identify patients in whom abnormal parathyroid tissue was removed at surgery.

Results: 31/ 2105 patients (1.47%) had a single macroscopically abnormal parathyroid gland removed (29 patients) and two glands (in 2 cases) sent for histopathology. Twenty eight patients were found to have histological evidence of a parathyroid adenoma or hyperplasia. Three patients had normal parathyroid histology. Preoperatively, 26 patients had no abnormal serum calcium detected, 3 patients had raised serum calcium level and in 3 patients serum calcium testing was not done. Postoperatively, 25 patients had normal calcium, six had temporary hypocalcaemia. Two patients had temporary recurrent laryngeal nerve palsy.

Conclusions: 1) We opine that the entity of PI is underreported and underinvestigated, 2) Though there is risk of removing a histologically normal gland, we believe that PI found during surgery should be excised as majority of them may be causing subclinical or early or normocalcemic hyperparathyroidism. Moreover, we have found this to be a safe procedure with minimal morbidity to the patient. By removing them at the original operation, the patient is saved complicated redo neck surgery, when clinically apparent primary hyperparthryoidism develops later, 3) The scenario of PI also emphasizes the need and provides a chance for routine clinical and biochemical evaluation for associated hyperparathyroidism in all cases of thyroid disease.

Keywords: Thyroidectomy, Parathyroid adenoma, Hyperplasia, Hypercalcemia, Calcium