MORPHOMETRIC AND ELECTRON-MICROSCOPIC ANALYSES OF THE EFFECTS OF GONADOTROPIN-RELEASING-HORMONE AGONISTS ON UTERINE LEIOMYOMAS

Objective.-Reports on the histologic effects of gonadotropin-releasing hormone agonists on uterine leiomyomas provide conflicting results. M ost previous studies used qualitative methods of analysis. Using quant itative and semiquantitative stereologic methods of analysis, we asses sed volume density of hyalinized areas, cell density, nuclear volume, and cytoplasmic cross-sectional areas of smooth muscle cells in histol ogic sections and also measured diameters of collagen fibrils in elect ron micrographs of uterine leiomyomas. Design.-Thirty leiomyomas from patients treated with gonadotropin-releasing hormone agonists (10 diff erent patient samples), age-matched control patients (10 different pat ient samples), and postmenopausal women (10 different patient samples) were used. Hyalinization was assessed using a microscope with a proje ction head and affixed morphometric grid. Cell size and density were e valuated using a video-based, computerized system attached to the micr oscope, for which morphometric ad hoc programs were written. Diameters of collagen fibrils were measured from electron micrographs. Setting. -The study was conducted in the Department of Pathology, Mount Sinai M edical Center, New York, NY. Patients.-A total of 30 patient samples w ere studied, with three groups comprising 10 samples each, including p atients treated with gonadotropin-releasing hormone agonists, age-matc hed control patients, and postmenopausal women. Results.-Myomas from p atients treated with gonadotropin-releasing hormone agonists exhibited more hyalinization, greater cell density, slightly smaller cell sizes , and larger collagen fibrils than those of age-matched control patien ts and postmenopausal women. Conclusions.-Shrinkage after treatment wi th gonadotropin-releasing hormone agonists is attributed to smaller ce ll size and increased collagenization in myomas.