Incidental detection of parathyroid adenomas on chest CT before clinical presentation of hyperparathyroidism

To evaluate whether parathyroid adenomas can be detected by thoracic radiologists on routine chest CT.

This retrospective study included patients with hyperparathyroidism evaluated by parathyroid scans and a control group with normal calcium. All had enhanced chest CT within 36 months prior to parathyroid imaging. Chest CTs were reviewed by 3 blinded thoracic radiologists. We report diagnostic accuracy for all positive findings and findings > 8 mm.

Our sample comprised 126 patients, 63 with confirmed hyperparathyroidism and 63 control patients; 6 parathyroid cases were excluded for being out of the field of view. Readers 1, 2, and 3 had sensitivity of 95%, 60%, and 35%, and specificity of 88%, 89%, and 97%, respectively. Specificity increased to 95%, 97%, and 98% when considering only findings larger than 8 mm. Review of false negative studies for reader 1 revealed 3 parathyroid adenomas visualized in retrospect. Review of the 7 false positive studies for reader 1 revealed candidate lesions in all of them attributed to exophytic thyroid nodules or lymph nodes. 90%, 67%, and 40% of the parathyroid adenoma patients had at least 1, 2, and 3 complications respectively. Most prevalent complications were nephrolithiasis (48%) and osteopenia (46%).

Routine contrast-enhanced chest CT can detect the majority of parathyroid adenomas with high specificity.

Increasing awareness of parathyroid adenomas by chest radiologists allow for detection of enlarged parathyroid glands, diagnosing hyperparathyroidism before clinical presentation.