Correlation of diameters of secretory granules in clinically non-functioning chromophobe adenomas of the pituitary with those of normal thyrotrophs.

Diameters of secretory granules in thyrotrophs in gonadotrophs were measured in electron micrographs of operation specimens of 4 pituitary glands and of the secretory granules in operation specimens of 10 clinically non-functioning chromophobe adenomas. The mean diameter of the thyrotroph granules was 137 plus or minus 26 nm, of the gonadotrophs 204 plus or minus 38 nm, of 9 of the adenomas 141 plus or minus 20 nm and of the remaining adenoma 248 plus or minus 67 nm. The significance of the close correlation in granule size in most of the adenomas with that of thyrotrophin granules is discussed briefly.