THE INDUCTION OF BENIGN EPITHELIAL NEOPLASMS OF THE OVARIES OF GUINEA-PIGS BY TESTOSTERONE STIMULATION - A POTENTIAL ANIMAL-MODEL

We studied the effects of different hormones on the epithelial cells o f the ovaries of 11 guinea pigs, Three received testosterone, two rece ived estrone, three megestrol, and three chorionic gonadotropin. Three control guinea pigs received sterile water, Benign epithelial cysts l arger than 1.5 mm were found in six guinea pigs, three who received te stosterone, one who received megestrol, and two who received chorionic gonadotropin. In one of the three guinea pigs who received testostero ne, 2.5-cm bilateral cysts were grossly identified. Papillary excresce nces were found on the ovarian surface in four guinea pigs, three who received testosterone and one who received megestrol. The proliferatin g epithelial cells also formed benign glands in the ovarian stroma in two guinea pigs who received testosterone. The most exuberant epitheli al proliferations, including large bilateral cystadenomas, papillary e xcrescence that formed a small papillary neoplasm, and glands in the o varian stroma that formed adenomatous areas, were seen in the guinea p ig who received an intermediate dose of testosterone for the longest t ime. By radioimmunoassay, the serum level of testosterone was 22 ng/dL in one of the controls and 10,000, 12,000, and 15,000 ng/dL in the th ree guinea pigs who received testosterone. In the guinea pig with the most exuberant epithelial proliferation, the level of testosterone in the uterus was similar to that in the serum (13,860 ng/mg), but in the wall of the ovarian epithelial cyst, it was three times higher than i t was in the serum (44,000 ng/mg), Our study shows that testosterone s timulates the growth of epithelial cells in the ovaries of guinea pigs , resulting in benign cysts, small adenomas in the ovarian parenchyma, and papillomas on the ovarian surface, The study also shows that guin ea pigs can be used as an animal model for epithelial tumors of the hu man ovary.