Cyclophosphamide, cisplatin, and leuprolide acetate in patients with debulked stage III or IV ovarian carcinoma

Current management strategies for ovarian cancer

Epithelial ovarian cancer originates in the layer of cells that covers the surface of the ovaries. The disease spreads readily throughout the peritoneal cavity and to the lymphatics, often before causing symptoms. Of the cancers unique to women, ovarian cancer has the highest mortality rate. Most women are diagnosed as having advanced stage disease, and efforts to develop new screening approaches for ovarian cancer are a high priority. Optimal treatment of ovarian cancer begins with optimal cytoreductive surgery followed by combination chemotherapy. Ovarian cancer, even in advanced stages, is sensitive to a variety of chemotherapeutics. Although improved chemotherapy has increased 5-year survival rates, overall survival gains have been limited because of our inability to eradicate all disease. Technologic advances that allow us to examine the molecular machinery that drives ovarian cancer cells have helped to identify numerous therapeutic targets within these cells. In this review, we provide an overview of ovarian cancer with particular emphasis on recent advances in operative management and systemic therapies.

Second-line therapy of advanced ovarian cancer with GnRH analogs

Ovarian cancer is still the first cause of death among female malignancies. The standard treatment adopted in ovarian cancer is a radical surgical treatment or cytoreduction, followed by six courses of platinum-based chemotherapy; second-line regimens are associated with severe side effects. GnRH analogs could represent an alternative therapeutical approach. The aim of our study was to evaluate the role of GnRH analogs in the management of platinum-resistant ovarian cancers. We enrolled 12 patients affected by advanced ovarian cancer, previously treated with six courses of platinum-paclitaxel. In second-line therapy, we used leuprolide on 1, 8, and 28 days of treatment. CA 125 levels were recorded for each patient. One case of clinical partial response was obtained (8.3%). Stable disease was diagnosed in three patients (25%). Progression was recorded in eight cases (66.7%). Progression-free survival was 6 months. The treatment was well tolerated by patients. The high tolerability and the results obtained with leuprolide versus platinum in second-line therapy might permit a better use of the analogs for advanced ovarian cancer.

Primary and salvage therapy with LH-RH analogues in ovarian cancer

The efficacy of modern surgical and chemotherapeutic options for the treatment of ovarian cancer is still unsatisfactory. In spite of the availability of new cytotoxic agents, the majority of ovarian cancer patients will finally die of chemoresistant disease. LH-RH agonists in conventional doses have been shown to induce objective responses in approximately 9% of patients with refractory ovarian cancer and disease stabilization in 26% of these women. As toxicity of LH-RH agonists is low or absent, and since their efficacy is not strikingly inferior to that of experimental chemotherapy, they have a vital indication in the salvage situation. A trial is presently being performed among platinum/taxol-refractory patients, comparing the impact of the LH-RH agonist leuprorelin and that of the cytotoxic agent treosulfane on survival and quality of life. The addition of LH-RH agonists in conventional doses to standard first-line surgical and chemotherapy does not improve relapse-free and overall survival. For many years it has been suggested that LH-RH agonists inhibit proliferation of ovarian cancer by suppressing endogenous gonadotropins, which were considered to be mitogenic in this malignancy. Recent experimental and clinical data have made this hypothesis questionable. In contrast, a large body of experimental evidence has emerged during the past few years indicating that LH-RH agonists and antagonists directly inhibit proliferation of ovarian cancer through LH-RH receptors expressed by 80% of these tumors. To exploit these direct antiproliferative effects of LH-RH analogues, higher tissue concentrations are necessary than those achieved with the conventional doses used today. Alternative routes of administration or higher systemic doses of potent LH-RH antagonists, such as Cetrorelix, might improve the efficacy of this approach. Clinical trials addressing this issue are under way. Finally, the LH-RH receptors expressed by ovarian cancers could be employed for targeted chemotherapy using cytotoxic LH-RH analogues. This approach has been shown to be effective in experimental models and might be tested in clinical trials in the near future.

Luteinizing hormone-releasing hormone agonist triptorelin in combination with cytotoxic chemotherapy in patients with advanced ovarian carcinoma. A prospective double blind randomized trial. Decapeptyl Ovarian Cancer Study Group

BACKGROUND

Several lines of evidence suggest that the proliferation of ovarian carcinoma might be stimulated by gonadotrophins. A number of Phase I/Phase II clinical trials have reported that the suppression of endogenous luteinizing hormone and follicle-stimulating hormone secretion by luteinizing hormone-releasing hormone (LHRH) analogs induced objective remissions and/or disease stabilization in 10-30% of patients with advanced refractory ovarian carcinoma. The current study was performed to evaluate whether the addition of LHRH agonist treatment to standard platinum-based chemotherapy could prolong survival of patients with surgically treated Stage III or IV epithelial ovarian carcinoma.

METHODS

One hundred and thirty-five patients with Stage III or IV epithelial ovarian carcinoma participated in this prospective randomized double blind trial. After cytoreductive surgery, 69 patients received monthly injections of a depot preparation of the LHRH agonist [D-Trp6] LHRH (triptorelin, 3.75 mg) and 66 patients received placebo until their deaths or termination of trial, respectively. All patients were treated with a standard platinum-based chemotherapy, and, if necessary, with second- or third-line cytotoxic regimens.

RESULTS

Endogenous gonadotrophins were reliably suppressed in patients treated with triptorelin. However, their progression free and overall survival were not significantly different from that of patients receiving placebo injections (statistical power > 80% for a difference between both groups of > or = 20%).

CONCLUSIONS

The results of this trial suggest that the suppression of endogenous gonadotrophins by conventional doses of an LHRH agonist produces no relevant beneficial effects in patients with advanced ovarian carcinoma who receive standard surgical cytoreduction and cytotoxic chemotherapy.