Luteinising hormone releasing hormone (LHRH) agonists for the treatment of relapsed epithelial ovarian cancer

Background Ovarian cancer is seventh most common cancer in women worldwide. Approximately 1.3% of women will be diagnosed with ovarian cancer at some point during their life time. The majority of tumours arise from surface of the ovary (epithelial). Two thirds of these women will present with advanced disease, requiring aggressive treatment, which includes debulking surgery (removal of as much disease as possible) and chemotherapy. However, most women (75%) with advanced epithelial ovarian cancer (EOC) will relapse following surgery and chemotherapy. Patients who relapse are treated with either platinum or non-platinum drugs and this is dependent on the platinum-sensitivity and platinum-free interval. These drug regimens are generally well-tolerated although there are potential severe side effects. New treatments that can be used to treat recurrence or prevent disease progression after first-line or subsequent chemotherapy are important, especially those with a low toxicity profile. Hormones such as luteinising hormone releasing hormone (LHRH) agonists have been used in the treatment of relapsed EOC. Some studies have shown objective remissions, while other studies have shown little or no benefit. Most small studies report a better side-effect profile for LHRH agonists when compared to standard chemotherapeutic agents used in EOC. Objectives To compare the effectiveness and safety of luteinising hormone releasing hormone (LHRH) agonists with chemotherapeutic agents or placebo in relapsed epithelial ovarian cancer (EOC). Search methods We searched the Cochrane Gynaecological Cancer Group trials register, Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE and Embase up to January 2016. We also searched registers of clinical trials and abstracts of scientific meetings. Selection criteria Randomised controlled trials (RCTs) that compared LHRH agonists with chemotherapeutic agents or placebo in relapsed EOC. Data collection and analysis Two review authors independently assessed whether relevant studies met the inclusion criteria, retrieved data and assessed risk of bias. Main results Two studies, including 97 women, met our inclusion criteria: one assessed LHRH agonist (leuprorelin) use in relapsed (platinum-resistant and platinum-refractory) EOC in comparison with a chemotherapeutic agent (treosulfan) (Du Bois 2002); the other examined LHRH agonist (decapeptyl) versus a placebo (Currie 1994). Since both studies had different control groups, a meta-analysis was not possible. There may be little or no difference between treatment with leuprorelin or treosulfan in overall survival (OS) (hazard ratio (HR) 0.98, 95% confidence interval (CI) 0.58 to 1.67; very low-quality evidence) or progression-free survival (PFS) at six and 12 months (risk ratio (RR) 0.61, 95% CI 0.22 to 1.68, and RR 0.65, 95% CI 0.12 to 3.66; very low-quality evidence), respectively (Du Bois 2002). The duration of follow-up was 2.5 years and quality of life (QoL) was not reported in this study. Alopecia and fatigue were probably more common with treosulfan than leuprorelin (alopecia RR 0.32, 95% CI 0.12 to 0.91 (very lowquality evidence)). There may be little or no difference in other Grade 3/4 side effects: nausea and vomiting (RR 0.65, 95% CI 0.12 to 3.66 (very low-quality evidence)); neurotoxicity (RR 0.32, 95% CI 0.01 to 7.71 (very low-quality evidence)) and neutropenia (RR 0.97, 95% 0.06 to 14.97 (very low-quality evidence)), The Currie 1994 study, which compared decapeptyl treatment with placebo, reported mean PFS of 16 weeks verus 11.2 weeks, respectively. No relative effects measures or P value at a particular time point were reported. Overall survival (OS) and QoL outcomes were not reported. In addition, adverse events were only mentioned for the decapeptyl group. Adverse events were incompletely reported (no adverse events in decapeptyl group, but not reported for the placebo group). Authors' conclusions Based on this review of two small RCTs, there is not enough evidence to comment on the safety and effectiveness of LHRH agonists in the treatment of platinum-refractory and platinum-resistant (relapsed) EOC. Overall, the quality of evidence for all outcomes (including OS, PFS, QoL and adverse events) is very low.