Efficacy of sequential cyclical hormonal therapy in endometrial cancer and its correlation with steroid hormone receptor status. Adjuvant progestagen therapy improves survival in patients with endometrial cancer after hysterectomy. Results of one-institutional prospective clinical trial. Megestrol and tamoxifen in patients with advanced endometrial cancer: an Eastern Cooperative Oncology Group Study (E4882). Tamoxifen and medroxyprogesterone therapy for advanced endometrial carcinoma. Oral medroxyprogesterone acetate in the treatment of advanced or recurrent endometrial carcinoma: a dose-response study by the Gynecologic Oncology Group.
Forty-six eligible women with metastatic endometrial cancer were randomly allocated to receive monthly cycles of either CAF (cyclophosphamide, adriamycin, 5-fluorouracil) or CAF plus Provera 200 mg daily for 3 weeks followed cyclically by Tamoxifen 20 mg daily for 3 weeks. Overall response rates of 15 and 43% were seen with CAF and CAF plus hormonal therapy. Using a multivariate analysis of the results, this difference is significant (P value 0.05). In 8 patients with operable endometrial cancer, negative estrogen receptor concentration (ER less than 15 fmole/mg protein) and Grade 3 disease, the clinical course was aggressive in 4 patients with systemic and local relapse. In 10 other similar patients (negative ER and Grade 3) who received adjuvant cyclical hormonal therapy only 1 relapsed and the other 9 are disease-free for an average of more than 31 months. Sequential cyclical hormonal therapy with ER and progesterone receptor analysis has a place in the management of endometrial carcinoma. A prospective study was conducted to determine the effectiveness of adjuvant hormonotherapy in endometrial cancer after surgery. Two hundred and five patients were randomly assigned to adjuvant progestagen treatment or were given no additional therapy. The follow-up was 5-years. We concluded that there was evidence of gain from adjuvant progestagen therapy in postoperative endometrial cancer. The group of patients who received progestagens had significantly longer survival than the control group without hormonotherapy (Logrank test; P < 0.001). To investigate the effect of adding tamoxifen to megestrol in the hormonal therapy for advanced endometrial cancer, 66 patients were entered in this study. Initially, 41 patients were randomized to either the standard progestin therapy of megestrol or to the combination of megestrol and tamoxifen between October 1982 and October 1984. The megestrol arm was terminated because of poor accrual and 25 patients were directly assigned to the combination arm. Among the 20 eligible cases on the megestrol arm, the response rate of 20% consisted of I complete response and 3 partial responses. The response rate on the megestrol plus tamoxifen arm was 19% with 1 (2%) complete response and 7 (17%) partial responses among 42 eligible cases. The median survival times were 12.0 months and 8.6 months, respectively. Only mild and moderate toxicities were observed on megestrol compared with more toxic complications observed on the combination of megestrol and tamoxifen, including a life-threatening case of pulmonary embolism. Although we could not carry out a comparative evaluation as intended, we conclude that the combination of megestrol and tamoxifen offers no clinical advantage over megestrol alone in the treatment of advanced endometrial carcinoma. We have studied the response rates and survival of a group of 93 patients with Stage III or IV endometrial adenocarcinoma after random allocation to therapy with tamoxifen (TAM) 20 mg twice daily (n = 45) or medroxyprogesterone acetate (MPA) 1 g/wk intramuscularly (n = 48). The patients were examined every 4 months. In the non-responders and in those who relapsed, combination therapy with TAM and MPA was given. Twenty-four of 45 (53.4%) responded to TAM alone, 27 of 48 (56.2%) responded to MPA alone. Of the responders 23 later relapsed in the TAM group and 24 in the MPA group and of these 14 (60.8%) and 15 (62.5%), respectively, responded to the combination therapy. Of the original 21 non-responders to MPA alone, 10 responded to the combination (47.6%) and 11 (52.4%) did not; the comparable figures for the TAM alone group were 13 (61.9%) and 8 (38.1%), respectively. Survival rates were much higher in the differentiated than in the undifferentiated carcinomas. In conclusion, we feel that the efficacy, and the few side-effects of these drugs used alone and particularly when used in sequential combination, make them a very attractive treatment for advanced endometrial adenocarcinoma. Progestins have definite activity against advanced or recurrent endometrial carcinoma. Both parenteral and oral progestins yield similar serum levels and response rates, which range from 18% to 34%. The one major study that used oral medroxyprogesterone acetate (MPA) noted a response rate at the lower end of the range (18%) and much poorer progression-free and overall survival times (4 and 10.5 months, respectively) than previously reported. The present study sought to confirm this earlier study of oral MPA, to assess the importance of prognostic factors such as histologic grade and receptor levels, and to determine whether a higher dose of MPA would yield a higher response rate.
                Two hundred ninety-nine eligible women with advanced or recurrent endometrial carcinoma were randomized to receive oral MPA either 200 mg/d or 1, 000 mg/d until unacceptable toxicity intervened or their disease progressed.
                Among 145 patients receiving the low-dose regimen, there were 25 complete (17%) and 11 partial (8%) responses for an overall response rate of 25%. The 154 patients receiving the high-dose regimen experienced 14 (9%) complete and 10 (6%) partial responses for an overall response rate of 15%. Median durations of progression-free survival were 3.2 months and 2.5 months for the low-dose and high-dose regimens, respectively. Median survival durations were 11.1 months and 7.0 months, respectively. The adjusted relative odds of responding to the high-dose regimen compared with the low-dose regimen was 0.61 (90% confidence interval, 0.36 to 1.04). Prognostic factors having a significant impact on the probability of response included initial performance status, age, histologic grade, and progesterone receptor concentration. Compliance with oral therapy was documented with serum levels 1 month after starting therapy, when possible. MPA levels were commensurate with the assigned dose and schedule.
                Oral MPA is active against endometrial carcinoma. Response to progestin therapy is more frequent among patients with a well-differentiated histology and positive progesterone receptor status. This study provides no evidence to support the use of MPA 1,000 mg/d orally instead of MPA 200 mg/d orally. In fact, the trends suggest the opposite. The use of oral MPA 200 mg/d is a reasonable initial approach to the treatment of advanced or recurrent endometrial carcinoma, particularly those lesions that are well-differentiated and/or progesterone receptor-positive (> 50 fmol/mg cytosol protein). Patients with poorly differentiated and/or progesterone receptor levels less than 50 fmol/mg cytosol protein had only an 8% to 9% response rate.