Adjuvant hormone therapy of primary endometrial carcinoma with oxyprogesterone caproate

The results of preoperative use of oxyprogesterone caproate (OPC) in 398 patients suffering from primary endometrial carcinoma are presented. The following characteristic histological changes of the tumor as a result of OPC treatment are noted: (1) decrease in the proliferative activity; (2) increase in the structural and functional differentiation, active secretion; (3) secretory exhaustion; (4) atrophic changes resulting in necrosis of the tumor and its complete or partial regression. Comparison of histology of the endometrium before OPC treatment and after surgery shows a complete regression of the tumor in 8.5% of cases, increase of differentiation and secretion in 54.8% of cases, and doubtful effect or its absence in 36.7% of cases. Random study of the role of adjuvant OPC treatment was carried out. In the group of 164 patients not treated with OPC, the 5-year survival rate was 78.6%, whereas in the group of 112 patients treated with OPC (10–16.0 g) before surgery, the 5-year survival rate was 85.7% ( P >0.05). The treatment with OPC was most effective in patients suffering from highly differentiated adenocarcinoma in combination with hyperestrogenecity, obesity, and diabetes mellitus. The frequency of recurrences and metastases among patients treated with OPC was considerably lower than among the patients of the control group. The clinical data on the use of OPC therapy as a component of the complex treatment of primary endomentrial cancer are presented.