Human Pituitary Tumors Secrete Chromogranin-A*

Chromogranin-A (CgA) has emerged as a serum and tissue marker for a number of endocrine tumors. We studied 15 patients with pituitary tumors to evaluate the clinical value of CgA as a serum and tissue marker for such tumors. One third of the patients had elevated serum CgA levels; 2 of these patients had nonsecreting pituitary tumors, and the other 3 had corticotroph adenomas. CgA-positive cells were detected in 9 of the 11 anterior pituitary tumors that were immunostained; in these 9 tumors at least half of the cells were CgA positive. We conclude that CgA production is common in pituitary tumors and that immunohistochemical studies for CgA may aid in their classification. In addition, serum CgA measurements may help to identify patients with pituitary tumors, especially those that do not secrete a known pituitary peptide.