Percutaneous aspiration for hormone levels in the diagnosis of functioning endocrine tumors.

Percutaneous aspiration to measure hormone levels in suspected functioning endocrine adenomas has been performed in 23 suspected cases of parathyroid adenomas, 7 cases of ACTH-producing thoracic carcinoid tumors, and 1 case of gastrinoma. When tumors secrete hormone or peptide markers, the biochemical assay can replace cytology to identify the lesion with greater specificity and at less expense.