[Hormone dependency and progestogen therapy in the treatment of endometrial cancer]

The anti-tumor activities of steroid compounds on endometrical cancer (Ishikawa cell line) were examined in vitro by human tumor clonogenic assay (HT CA). Clinically effective progestational compounds including medroxyprogesterone acetate (MAP), and 17 alpha hydroxy-progesterone caproate were effective. Norethindrone (ENT), which is also a potent progestational compound, and RU486, which is known to be a progesterone antagonist were ineffective in this in vitro system, neither having any influence on the effect of MAP. These results indicated that the anti-tumor activity of MAP did not proceed via the so-called progesterone receptor system. Morphological changes induced by MAP in undifferentiated endometrial cancer, the effectiveness of tamoxifen, hormonochemotherapy, and the use of MAP for adjuvant therapy and prophylaxis were also discussed.