Efficacy of intranasal or subcutaneous luteinizing hormone-releasing hormone agonist inhibition of ovarian function in the treatment of endometriosis

A review of phase II and III drugs for the treatment and management of endometriosis

INTRODUCTION

Endometriosis is an estrogen-dependent disease that gives rise to pelvic pain and infertility. Although estroprogestins and progestins currently stand as the first-line treatments for this condition, demonstrating efficacy in two-thirds of patients, a significant portion of individuals experience only partial relief or symptom recurrence following the cessation of these therapies. The coexistence of superficial, deep endometriosis, and ovarian endometriomas, as three distinct phenotypes with unique pathogenetic and molecular characteristics, may elucidate the current heterogeneous biological response to available therapy.

AREAS COVERED

The objective of this review is to furnish the reader with a comprehensive summary pertaining to phase II-III hormonal treatments for endometriosis.

EXPERT OPINION

Ongoing research endeavors are directed toward the development of novel hormonal options for this benign yet debilitating disease. Among them, oral GnRH antagonists emerge as a noteworthy option, furnishing rapid therapeutic onset without an initial flare-up; these drugs facilitate partial or complete estrogen suppression, and promote prompt ovarian function recovery upon discontinuation, effectively surmounting the limitations associated with previously employed GnRH agonists. Limited evidence supports the use of selective estrogen and progesterone receptor modulators. Consequently, further extensive clinical research is imperative to garner a more profound understanding of innovative targets for novel hormonal options.

Clinical Efficacy, Pharmacokinetics, and Safety of the Available Medical Options in the Treatment of Endometriosis-Related Pelvic Pain: A Scoping Review

BACKGROUND

In this scoping review, we sought to identify published studies evaluating the drugs currently used in the treatment of endometriosis-related pelvic pain, with reflection on their chemical properties, pharmacokinetics, safety profile, and clinical efficacy.

METHODS

A literature search was conducted with the use of the PubMed and EMBASE electronic databases, focusing on identifying articles published in English between January 1990 and 2023.

RESULTS

Based on the included studies, current therapy options for the treatment of endometriosis-related pain identified and reviewed in this article were: (1) non-steroidal anti-inflammatory drugs; (2) combined oral contraceptive (COCs); (3) progestins; (4) gonadotropin-releasing hormone agonists and antagonists; (5) aromatase inhibitors (AIs); (6) selective estrogen and progesterone receptor modulators; and (7) levonorgestrel-intrauterine device.

CONCLUSIONS

Based on the published evidence, clinicians should consider NSAIDs, COCs, and progestins as the first-line medical therapies. Compared with second-line options, such as GnRH agonists/antagonists or AIs, the abovementioned first-line options are well tolerated, efficacious, and exhibit lower overall price. Future research priorities should be to identify novel target therapies and to evaluate the effects of available drugs through different routes of administration.

Gonadotropin-releasing hormone analogues for endometriosis

BACKGROUND

Endometriosis is a common gynaecological condition affecting 6 to 11% of reproductive-age women and may cause dyspareunia, dysmenorrhoea, and infertility. One treatment strategy is medical therapy with gonadotrophin-releasing hormone analogues (GnRHas) to reduce pain due to endometriosis. One of the adverse effects of GnRHas is a decreased bone mineral density. In addition to assessing the effect on pain, quality of life, most troublesome symptom and patients' satisfaction, the current review also evaluated the effect on bone mineral density and risk of adverse effects in women with endometriosis who use GnRHas versus other treatment options.

OBJECTIVES

To assess the effectiveness and safety of GnRH analogues (GnRHas) in the treatment of painful symptoms associated with endometriosis and to determine the effects of GnRHas on bone mineral density of women with endometriosis.

SEARCH METHODS

We searched the Cochrane Gynaecology and Fertility (CGF) Group trials register, CENTRAL, MEDLINE, Embase, PsycINFO and the trial registries in May 2022 together with reference checking and contact with study authors and experts in the field to identify additional studies.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) which compared GnRHas with other hormonal treatment options, including analgesics, danazol, intra-uterine progestogens, oral or injectable progestogens, gestrinone and also GnRHas compared with no treatment or placebo. Trials comparing GnRHas versus GnRHas in conjunction with add-back therapy (hormonal or non-hormonal) or calcium-regulation agents were also included in this review.  DATA COLLECTION AND ANALYSIS: We used standard methodology as recommended by Cochrane. Primary outcomes are relief of overall pain and the objective measurement of bone mineral density. Secondary outcomes include adverse effects, quality of life, improvement in the most troublesome symptoms and patient satisfaction.  Due to high risk of bias associated with some of the studies, primary analyses of all review outcomes were restricted to studies at low risk of selection bias. Sensitivity analysis including all studies was then performed.

MAIN RESULTS

Seventy-two studies involving 7355 patients were included. The evidence was very low to low quality: the main limitations of all studies were serious risk of bias due to poor reporting of study methods, and serious imprecision.  Trials comparing GnRHas versus no treatment  We did not identify any studies. Trials comparing GnRHas versus placebo There may be a decrease in overall pain, reported as pelvic pain scores (RR 2.14; 95% CI 1.41 to 3.24, 1 RCT, n = 87, low-certainty evidence), dysmenorrhoea scores (RR 2.25; 95% CI 1.59 to 3.16, 1 RCT, n = 85, low-certainty evidence), dyspareunia scores (RR 2.21; 95% CI 1.39 to 3.54, 1 RCT, n = 59, low-certainty evidence), and pelvic tenderness scores (RR 2.28; 95% CI 1.48 to 3.50, 1 RCT, n = 85, low-certainty evidence) after three months of treatment. We are uncertain of the effect for pelvic induration, based on the results found after three months of treatment (RR 1.07; 95% CI 0.64 to 1.79, 1 RCT, n = 81, low-certainty evidence). Besides, treatment with GnRHas may be associated with a greater incidence of hot flushes at three months of treatment (RR 3.08; 95% CI 1.89 to 5.01, 1 RCT, n = 100, low-certainty evidence). Trials comparing GnRHas versus danazol For overall pain, for women treated with either GnRHas or danazol, a subdivision was made between pelvic tenderness, partly resolved and completely resolved. We are uncertain about the effect on relief of overall pain, when a subdivision was made for overall pain (MD -0.30; 95% CI -1.66 to 1.06, 1 RCT, n = 41, very low-certainty evidence), pelvic pain (MD 0.20; 95% CI -0.26 to 0.66, 1 RCT, n = 41, very low-certainty evidence), dysmenorrhoea (MD 0.10; 95% CI -0.49 to 0.69, 1 RCT, n = 41, very low-certainty evidence), dyspareunia (MD -0.20; 95% CI -0.77 to 0.37, 1 RCT, n = 41, very low-certainty evidence), pelvic induration (MD -0.10; 95% CI -0.59 to 0.39, 1 RCT, n = 41, very low-certainty evidence), and pelvic tenderness (MD -0.20; 95% CI -0.78 to 0.38, 1 RCT, n = 41, very low-certainty evidence) after three months of treatment. For pelvic pain (MD 0.50; 95% CI 0.10 to 0.90, 1 RCT, n = 41, very low-certainty evidence) and pelvic induration (MD 0.70; 95% CI 0.21 to 1.19, 1 RCT, n = 41, very low-certainty evidence), the complaints may decrease slightly after treatment with GnRHas, compared to danazol, for six months of treatment. Trials comparing GnRHas versus analgesics  We did not identify any studies. Trials comparing GnRHas versus intra-uterine progestogens We did not identify any low risk of bias studies. Trials comparing GnRHas versus GnRHas in conjunction with calcium-regulating agents There may be a slight decrease in bone mineral density (BMD) after 12 months treatment with GnRHas, compared to GnRHas in conjunction with calcium-regulating agents for anterior-posterior spine (MD -7.00; 95% CI -7.53 to -6.47, 1 RCT, n = 41, very low-certainty evidence) and lateral spine (MD -12.40; 95% CI -13.31 to -11.49, 1 RCT, n = 41, very low-certainty evidence).  AUTHORS' CONCLUSIONS: For relief of overall pain, there may be a slight decrease in favour of treatment with GnRHas compared to placebo or oral or injectable progestogens. We are uncertain about the effect when comparing GnRHas with danazol, intra-uterine progestogens or gestrinone. For BMD, there may be a slight decrease when women are treated with GnRHas, compared to gestrinone. There was a bigger decrease of BMD in favour of GnRHas, compared to GnRHas in conjunction with calcium-regulating agents. However, there may be a slight increase in adverse effects when women are treated with GnRHas, compared to placebo or gestrinone. Due to a very low to low certainty of the evidence, a wide range of outcome measures and a wide range of outcome measurement instruments, the results should be interpreted with caution.

Advances in targeting estrogen synthesis and receptors in patients with endometriosis

INTRODUCTION

Endometriosis is an estrogen-dependent disease on the background of progesterone resistance. Increased estrogen production, low estrogen metabolization, and altered estrogen receptors (ERs) expression contribute to the hyperestrogenic milieu within endometriotic lesions. Since estrogens play a crucial role in the pathogenesis of the disease, inhibition of estrogen production is one of the main targets of available and emerging drugs.

AREAS COVERED

Firstly, we described the molecular alterations responsible for estrogen dependence. Secondly, we reviewed available and emerging treatments that interfere, through central (gonadotropin-releasing hormone analogs (GnRH-a), GnRH antagonists) or local mechanisms (aromatase inhibitors (AIs), inhibitors of steroid sulfatase (STS) and hydroxysteroid dehydrogenase type 1 (17β-HSD1)), with estrogen dependence. Finally, we focused on emerging treatments targeting ERs (selective estrogen receptor modulators (SERMs), estrogen receptors agonists, and antagonists).

EXPERT OPINION

Available treatments interfering with estrogen pathways exert a contraceptive effect, have hypoestrogenic side effects, and cannot prevent or definitively treat the disease. Preclinical and animal studies are focusing on emerging drugs targeting ERs in order to overcome limitations of available treatments. These treatments may represent a promising option, as they may produce a more specific inhibition of disease activity within endometriotic implants, avoiding prolonged hypoestrogenic status and limiting systemic side effects.

Gonadotropin-releasing hormone analogs: Mechanisms of action and clinical applications in female reproduction

Extra-hypothalamic GnRH and extra-pituitary GnRH receptors exist in multiple human reproductive tissues, including the ovary, endometrium and myometrium. Recently, new analogs (agonists and antagonists) and modes of GnRH have been developed for clinical application during controlled ovarian hyperstimulation for assisted reproductive technology (ART). Additionally, the analogs and upstream regulators of GnRH suppress gonadotropin secretion and regulate the functions of the reproductive axis. GnRH signaling is primarily involved in the direct control of female reproduction. The cellular mechanisms and action of the GnRH/GnRH receptor system have been clinically applied for the treatment of reproductive disorders and have widely been introduced in ART. New GnRH analogs, such as long-acting GnRH analogs and oral nonpeptide GnRH antagonists, are being continuously developed for clinical application. The identification of the upstream regulators of GnRH, such as kisspeptin and neurokinin B, provides promising potential to develop these upstream regulator-related analogs to control the hypothalamus-pituitary-ovarian axis.

Novel drug delivery methods for improving efficacy of endometriosis treatments

INTRODUCTION

Pharmacotherapy has a key role in the management of endometriosis. However, a significant proportion of patients gains only intermittent or limited benefits. In this regard, alternative and novel drug delivery methods are of paramount importance to improve efficacy and compliance of available treatments and develop alternative medical approaches.

AREAS COVERED

This review aims to provide the reader with a complete overview of available evidence about alternative and novel drug delivery methods for endometriosis pharmacotherapy and highlight new research lines.

EXPERT OPINION

Progestins and estroprogestins, which represent the first-line therapy, are already available in different formulations, being employed for contraception. Nevertheless, evidence on their adoption is still limited for some drug delivery methods, such as vaginal rings, patches, and subcutaneous implants. Further research is needed to define better their clinical utility in patients with endometriosis. Nanotechnologies have been investigated as novel drug delivery methods able to target the drug at the disease level. However, data are very limited and preliminary, and further research is needed to consider a possible clinical application in endometriosis.

[Endometriosis medical treatment: Hormonal treatment for the management of pain and endometriotic lesions recurrence. CNGOF-HAS Endometriosis Guidelines]

The available literature, from 2006 to 2017, on hormonal treatment has been analysed as a contribution to the HAS-CNGOF task force for the treatment of endometriosis. Available data are heterogeneous and the general level of evidence is moderate. Hormonal treatment is usually offered as the primary option to women suffering from endometriosis. It cannot be used in women willing to conceive. In women who have not been operated, the first line of hormonal treatment includes combined oral contraceptives (COC) and the levonorgestrel-releasing intra uterine system (52mg LNG-IUS). As a second line, desogestrel progestin only pills, etonogestrel implants, GnRH analogs (GnRHa) with add back therapy and dienogest can be offered. Add back therapy should include estrogens to prevent bone loss and improve quality of life, it can be introduced before the third month of treatment to prevent side effects. The literature does not support preoperative hormonal treatment for the sole purpose of reducing complications or recurrence, or facilitating surgical procedures. After surgical treatment, hormonal treatment is recommended to prevent pain recurrence and improve quality of life. COCs or LNG IUS are recommended as a first line. To prevent recurrence of endometriomas COC is advised and maintained as long as tolerance is good in the absence of pregnancy plans. In case of dysmenorrhea, postoperative COC should be used in a continuous scheme. GnRHa are not recommended in the sole purpose of reducing endometrioma recurrence risk.

Buserelin alleviates chloride transport defect in human cystic fibrosis nasal epithelial cells

Cystic fibrosis (CF) is the most common autosomal recessive disease in Caucasians caused by mutations in the gene encoding the Cystic Fibrosis Transmembrane conductance Regulator (CFTR) chloride (Cl-) channel regulated by protein kinases, phosphatases, divalent cations and by protein-protein interactions. Among protein-protein interactions, we previously showed that Annexin A5 (AnxA5) binds to CFTR and is involved in the channel localization within membranes and in its Cl- channel function. The deletion of phenylalanine at position 508 (F508del) is the most common mutation in CF which leads to an altered protein (F508del-CFTR) folding with a nascent protein retained within the ER and is quickly degraded. We previously showed that AnxA5 binds to F508del-CFTR and that its increased expression due to a Gonadoliberin (GnRH) augments Cl- efflux in cells expressing F508del-CFTR. The aim of the present work was to use the GnRH analog buserelin which is already used in medicine. Human nasal epithelial cells from controls and CF patients (F508del/F508del) were treated with buserelin and we show here that the treatment alleviates Cl- channel defects in CF cells. Using proteomics we highlighted some proteins explaining this result. Finally, we propose that buserelin is a potential new pharmaceutical compound that can be used in CF and that bronchus can be targeted since we show here that they express GnRH-R.

[Medical treatment of endometriosis: Hormonal treatment of pain, impact on evolution and future perspectives]

CONTEXT

Endometriosis is a chronic painful disease, for which hormone therapy is usually offered as a first line option to women not willing to conceive.

OBJECTIVES

To analyse and synthesize the literature, from 2006 onwards, on pain control, and disease evolution in oemn using combined hormonal contraceptives, progestins and GnRH analogs. Data on other current and future treatment perspectives is included as well.

SOURCES

Medline (Pubmed), the Cochrane Library, and endometriosis treatment recommendations published by European Society of Human Reproduction and Embryology (ESHRE), National Institute for health and Care Excellence (NICE), American College of Obstetricians and Gynecologists (ACOG), Royal College of Obstetricians and Gynaecologists (RCOG) and Société des Obstétriciens et Gynécologues du Canada (SOGC).

STUDY SELECTION

Meta-analysis and clinical trials are included.

RESULTS

Study quality is heterogeneous in general. Hormone therapy inconstantly allows pain relief and prevention of endometrioma and rectovaginal wall nodules recurrence. Available molecules and routes of administration as well as risk benefit balance are evaluated. Data on future perspectives are limited to date and do not allow use in routine.

CONCLUSION

Hormonal treatment of endometriosis relies on combined hormonal contraceptives (using different routes of administration), progestins and particularly the levonorgestrel-releasing IUS, and GnRH analogs as a last option, in combination with an add-back therapy. Promising alternatives are currently under preclinical and clinical evaluation.

Gonadotrophin-releasing hormone analogues for pain associated with endometriosis

EDITORIAL NOTE

See https://pubmed.ncbi.nlm.nih.gov/37341141/ for a more recent review that covers this topic and has superseded this review.

BACKGROUND

Endometriosis is a common gynaecological condition, characterised by the presence of endometrial tissue in sites other than the uterine cavity (excluding adenomyosis) that frequently presents with pain. The gonadotrophin-releasing hormone analogues (GnRHas) comprise one intervention that has been offered for pain relief in pre-menopausal women. GnRHas can be administered intranasally, by subcutaneous, or intramuscular injection. They are thought to result in down regulation of the pituitary and induce a hypogonadotrophic hypogonadal state.

OBJECTIVES

To determine the effectiveness and safety of GnRHas in the treatment of the painful symptoms associated with endometriosis.

SEARCH STRATEGY

Electronic searches of the Cochrane Menstrual Disorders and Subfertility Group specialist register, CENTRAL, MEDLINE, EMBASE, PSYCInfo and CINAHL were conducted in April 2010 to identify relevant randomised controlled trials (RCTs).

SELECTION CRITERIA

RCTs of GnRHas as treatment for pain associated with endometriosis versus no treatment, placebo, danazol, intra-uterine progestagens, or other GnRHas were included. Trials using add-back therapy, oral contraceptives, surgical intervention, GnRH antagonists or complementary therapies were excluded.

DATA COLLECTION AND ANALYSIS

Quality assessment and data extraction were performed independently by two reviewers. The primary outcome was pain relief. Relative risk was used as the measure of effect for dichotomous data. For continuous data, mean differences or standardised mean differences were used.

MAIN RESULTS

Forty one trials (n=4935 women) were included. The evidence suggested that GnRHas were more effective at symptom relief than no treatment/placebo. There was no statistically significant difference between GnRHas and danazol for dysmenorrhoea RR 0.98 (95%CI 0.92 to 1.04; P = 0.53). This equates to 3 fewer women per 1000 (95%CI 12 to 6) with symptomatic pain relief in the GnRHa group. More adverse events were reported in the GnRHa group. There was a benefit in overall resolution for GnRHas RR1.10 (95%CI 1.01 to 1.21, P=0.03) compared with danazol. There was no statistically significant difference in overall pain between GnRHas and levonorgestrel SMD -0.25 (95%CI -0.60 to 0.10, P=0.46). Evidence was limited on optimal dosage or duration of treatment for GnRHas. No route of administration appeared superior to another.

AUTHORS' CONCLUSIONS

GnRHas appear to be more effective at relieving pain associated with endometriosis than no treatment/placebo. There was no evidence of a difference in pain relief between GnRHas and danazol although more adverse events reported in the GnRHa groups. There was no evidence of a difference in pain relief between GnRHas and levonorgestrel and no studies compared GnRHas with analgesics.

Pain scoring in endometriosis: entry criteria and outcome measures for clinical trials. Report from the Art and Science of Endometriosis meeting

Standardized entry criteria and outcome measures for clinical trials in endometriosis-related pain would facilitate the comparison of trial results and the production of systematic reviews, improving evidence-based practice in this area. This report summarizes the recommendations from an international meeting for these criteria.

WITHDRAWN: Gonadotrophin-releasing hormone analogues for pain associated with endometriosis

BACKGROUND

Endometriosis is a common gynaecological condition that frequently presents with the symptom of pain. The precise pathogenesis (mode of development) of endometriosis is unclear but it is evident that endometriosis arises by the dissemination of endometrium to ectopic sites and the subsequent establishment of deposits of ectopic endometrium. The observation that endometriosis is rarely seen in the hypo-oestrogenic (low levels of oestrogen) post-menopausal woman led to the concept of medical treatment by induction of a pseudo-menopause using Gonadotrophin Releasing Hormone Analogues (GnRHas). When administered in a non-pulsatile manner (the pituitary is normally stimulated by pulses of natural GnRH and all analogues act on the pituitary at a constant level) their use results in down regulation (switching off) of the pituitary and a hypogonadotrophic hypogonadal state (low levels of female hormones due to non stimulation of the ovary).

OBJECTIVES

To determine the effectiveness of Gonadotrophin Releasing Hormone analogues (GnRHas) in the treatment of the painful symptoms of endometriosis by comparing them with no treatment, placebo, other recognised medical treatments, and surgical interventions.

SEARCH STRATEGY

The search strategy of the Menstrual Disorders and Subfertility review group (please see Review Group details) was used to identify all randomised trials of the use of GnRHas for the treatment of the painful symptoms of endometriosis.

SELECTION CRITERIA

Trials were included if they were randomised, and considered the effectiveness of GnRHas in the treatment of the painful symptoms of endometriosis.

DATA COLLECTION AND ANALYSIS

Twenty-six studies had data appropriate for inclusion in the review. The largest group (15 studies) compared GnRHas with danazol. There are five studies comparing GnRHas with GnRHas plus add-back therapy, three comparing GnRHa with GnRHa in a different form or dose, one compares them with gestrinone, one with the combined oral contraceptive pill, and one with placebo. Data was extracted independently by two reviewers. The authors of eleven studies have been contacted to clarify missing or unclear data. Only four have replied to date. Data on relief of pain, change in revised American Fertility Society (rAFS) scores, and side effects was collected.

MAIN RESULTS

No difference was found between GnRHas and any of the other active comparators with respect to pain relief or reduction in endometriotic deposits. The side effect profiles of the different treatments were different, with danazol and gestrinone having more androgenic side effects, while GnRHas tend to produce more hypo-oestrogenic symptoms.

AUTHORS' CONCLUSIONS

There is little or no difference in the effectiveness of GnRHas in comparison with other medical treatments for endometriosis. GnRHas do appear to be an effective treatment. Differences that do exist relate to side effect profiles. Side effects of GnRHas can be ameliorated by the addition of addback therapy.

The physiological basis of human sexual arousal: neuroendocrine sexual asymmetry

Normal sexual arousal and response suppose an integrated process involving both physiological and psychological processes. However, the current understanding of sexual arousal does not provide a coherent model that accounts for the integration of multiple physiological systems that subsequently generate a coordinated sexual response at both the spinal peripheral and cerebral central levels. Herein we suggest a model that involves both sympathetic and parasympathetic activation during sexual arousal via the two classes of gonadal hormones, androgens and oestrogens. We discuss the manner in which gonadal hormones may activate such a system, transforming pre-pubertal (non-erotic) genital stimulation to post-pubertal erogenization of stimulation and subsequent sexual arousal. Finally, we indicate that the different balance of androgens and oestrogens in men and women may generate asymmetric effects on each of the components of the autonomic nervous system, thereby explaining some of the differences in patterns of sexual arousal and the responses cycle across the sexes.

Dienogest is as effective as triptorelin in the treatment of endometriosis after laparoscopic surgery: results of a prospective, multicenter, randomized study

OBJECTIVE

To compare the efficacy of Dienogest versus Decapeptyl at 3.75 mg as consolidation therapy for surgery in the treatment of endometriosis.

DESIGN

Multicenter, open, randomized, parallel-group clinical trial.

SETTING

Volunteer patients in an academic research environment.

PATIENT(S)

Women with grade 2, 3, and 4 (</=70) endometriosis at initial laparoscopy.

INTERVENTION(S)

We provided 16 weeks of treatment with Dienogest, 1 mg tablet daily; or with Decapeptyl, 3.75 mg IM injection every 4 weeks.

MAIN OUTCOME MEASURE(S)

A change in the patient's Revised American Fertility Society score at the post-treatment laparoscopy.

RESULT(S)

From June 1994 to July 1998, 142 patients were enrolled in the trial. After exclusion for major protocol deviations, 59 patients were included in the Dienogest group and 61 in the Decapeptyl group. This study group was comparable to the first inclusion group. The patient demographic and clinical characteristics, median duration of endometriosis, Revised American Fertility Society scores, and Visual Analogic Squale (VAS) scores were comparable in both groups. Statistical analysis of efficacy was not significantly different between the two groups. Adverse events were reported by 87.7% of patients in the Dienogest group and 85.1% in the Decapeptyl group. Neither treatment affected patient body weight or vital signs.

CONCLUSION(S)

Dienogest is as effective as Decapeptyl for consolidation therapy after surgery for the treatment of endometriosis. The safety profile of dienogest differed from Decapeptyl (3.75 mg). Dienogest constitutes a new therapeutic alternative to the GnRH analogues.

Medical and surgical therapies for pain associated with endometriosis

Endometriosis is a common condition for which a number of treatments have been proposed. Medical treatments are based on the hormonal responsiveness of endometriosis implants. These therapies include progestins (with or without estrogens), androgens, and gonadotropin-releasing hormone (GnRH) analogs. Surgical treatments may include hysterectomy with oophorectomy or organ-sparing surgery involving ablation or resection of visible lesions of endometriosis and restoration of pelvic anatomy. There are no studies that directly compare the effectiveness or adverse effects of medical therapy and surgical therapy. Studies on medical therapy compare different treatments with placebo or with other active treatments. Hormone-based therapies for endometriosis show 80%-100% effectiveness in relief of pelvic pain over a 6-month course of therapy. Serious adverse outcomes after medical therapy are unusual. Studies on surgical therapy are largely anecdotal, with noncomparative reports on a variety of surgical methods. A few comparative surgical studies have been reported. Because of the noncomparative nature of many of the surgical studies, the use of combinations of surgical procedures and techniques in the reported studies, and the reporting of results from surgeons with an unusually high level of technical skill, the gynecological practitioner has little basis in the literature for assessing the optimum surgical approach. Surgical complications are believed to be underreported and may be related to how aggressive a surgical procedure is undertaken.

The evidence for the management of endometriosis

This review article has focussed on identifying the evidence from randomized controlled trials for the medical and surgical management of endometriosis. A critical summary of the medical management has shown that there is little difference in effectiveness of various medical treatments, but there are differences in the side-effect profiles. Few randomized controlled trials have been undertaken in surgery, but these have shown that surgical management is effective in the management of both painful symptoms and subfertility.

The effect of gonadotropin-releasing hormone agonist on type I collagen C-telopeptide and N-telopeptide: the predictive value of biochemical markers of bone turnover

To evaluate the clinical utility of recently developed biochemical markers in the assessment of bone metabolism during GnRH agonist (GnRHa) treatment, we compared five bone resorption markers [C-telopeptide (CTX) and N-telopeptide (NTX) of type I collagen, hydroxyproline (Hpr), pyridinoline (Pyr), and deoxypyridinoline (Dpyr)] and two bone formation markers [total alkaline phosphatase (Alp) and osteocalcin (OC)]. Sixty-eight normally menstruating women were injected with a long-acting GnRHa once a month for 24 weeks for the treatment of endometriosis or leiomyoma. The mean percentage bone loss at the lumbar spine was 3.79% at the end of treatment. Although levels of all markers increased significantly as the treatment progressed, CTX and NTX exhibited the highest correlation coefficients between bone loss at 24 weeks and the seven markers measured at 0, 4, 12, 16, and 24 weeks of treatment. Serum estradiol levels were similarly suppressed during the treatment in both fast losers (whose bone loss was more than the mean) and slow losers (whose bone loss was less than the mean). However, significantly higher z-scores of bone resorption markers, but not of bone formation markers, were observed in the fast losers at 24 weeks of treatment, suggesting a more accelerated bone resorption in this group. Whereas the three highest z-scores at 24 weeks of treatment were CTX, NTX, and Dpyr (in that order), the highest z-score (P < 0.05) was observed for CTX in the fast losers. The subjects in the highest quartile of CTX, the highest, and second highest quartiles of NTX at 24 weeks of treatment experienced 2.1, 2.2, and 1.7 times more bone loss (P < 0.001), respectively, than those in the lowest quartiles. Furthermore, the subjects in the highest quartile of both CTX and NTX experienced 3.6 times more bone loss (P < 0.001) than those in the lowest quartile of both markers. These results indicate that both CTX and NTX are useful and sensitive markers for bone resorption in a hypoestrogenic state induced by GnRHa.

Management of stage III and IV endometriosis: a 10-year experience

A retrospective analysis is reported of the management of 117 cases of infertility associated with Stage III and IV endometriosis. Combined medico-microsurgical treatment was selected in 75.3% of Stage III cases and in 83.3% of those on Stage IV. Medication consisted of medroxyprogesterone acetate in 26 patients and danazol in the remaining 64. Microsurgery alone was utilized in 24.7% of Stage III patients and in 16.6% of those on Stage IV. Both surgery alone and the combined therapy had a profound positive effect on subjective symptoms: dysmenorrhea, dyspareunia and pelvic pain. Following combined therapy, pregnancy was achieved in 34.4% of all women. Respective figures are 30.7% for medroxyprogesterone acetate (29.4% Stage III and 33.3% Stage IV) and 35.9% for danazol (37.7% Stage III and 27.2% Stage IV). In the group of patients treated by surgery alone, pregnancy occurred in 25.9%. Of the pregnancies in women with Stage III endometriosis, 25 were carried to term and 6 ended with a spontaneous abortion; figures for Stage IV women are 5 and 2, respectively. Second-look laparoscopy was performed in 49 of the 79 patients who failed to conceive, at 12-36 months after treatment; persistent genital pathology, to which infertility could be attributed, was found in 77.5% of them.

Endometriosis: medical therapy

The management of women with endometriosis is complex and necessitates individualization of patient care. The most commonly used medical therapies are danazol, GnRH agonists, medroxyprogesterone acetate and gestrinone. Studies to date have shown these drugs to have equal efficacy in terms of reduction in laparoscopic score and relief of symptoms. However, their side-effects make them unsuitable for long-term use. The addition of low dose hormone replacement therapy to GnRH agonist regimens may allow prolonged use but the current cost of these agents is high. Low dose oral contraceptive pills deserve further investigation. The role of medical treatment for women with endometriosis and infertility is controversial. There is no place for hormonal therapy in such women with stage I or II disease. When expectant management fails, gamete intrafallopian transfer offers excellent results. For those with stage III or IV disease, surgery is preferable with adjunctive medical therapy in selected cases. If pregnancy does not ensue, in vitro fertilization and embryo transfer are the next line of management, and results are optimized by prior medical therapy and aspiration of endometriomas. Major advances have been made in the medical management of endometriosis. However, current treatment strategies are ineffective in eliminating the disease in most women. New approaches are required in both basic and clinical research in order to finally eradicate this often devastating disease.

Buserelin acetate in the treatment of pelvic pain associated with minimal and mild endometriosis: a controlled study

OBJECTIVE

To evaluate the changes of pain symptoms induced by buserelin acetate, a gonadotropin-releasing hormone agonist, in a group of patients with endometriosis.

DESIGN

Thirty-five infertile patients with one or more of the following symptoms (dysmenorrhea, pelvic pain, deep dyspareunia, and endometriosis stage I or II) were allocated randomly to treatment with buserelin acetate 1,200 micrograms/d IN for 6 months (n = 19) or expectant management (n = 16). Pain symptoms were recorded by the women themselves using a questionnaire that included two scales for pain evaluation: one analogue and one multidimensional. The treated and untreated patients were followed for a minimum of 18 and 12 months from the time of randomization, respectively.

RESULTS

Buserelin acetate markedly reduced dysmenorrhea, pelvic pain, and dyspareunia during the treatment and also for the 12 subsequent months. During follow-up of the expectant management group, dysmenorrhea resolved in 19% (3/16) of the cases, and pelvic pain did not recur after diagnostic laparoscopy in one of the three women affected nor did deep dyspareunia in two of the five who reported the symptom before laparoscopy.

CONCLUSION

Buserelin acetate induced a significant improvement of pain symptoms that persisted in approximately half of the patients even after withdrawal of the drug. However, symptoms associated with endometriosis showed a spontaneous remission in approximately one fifth of the untreated patients.

Cholesterol fractions and apolipoproteins during endometriosis treatment by a gonadotrophin releasing hormone (GnRH) agonist implant or by danazol

OBJECTIVE

The evaluation of cholesterol fractions and apoproteins during ovarian suppression by a GnRH agonist implant vs danazol in the treatment of endometriosis.

DESIGN

A randomized study in 33 patients comparing goserelin (3.6 mg/4 weeks s.c., n = 20) with danazol (2 x 400 mg/day p.o., n = 13) in patients with a laparoscopic diagnosis of endometriosis and treated for 6 months.

MEASUREMENTS

Triglycerides, cholesterol (C), LDL-C, HDL-C subfractions and apoproteins A-1 and B were measured at admission, at months 2, 4 and 6 of treatment and at month 2 post-treatment.

RESULTS

After 1 month of therapy, serum oestradiol levels were maintained in the menopausal range with goserelin and in the early follicular phase range with danazol. Goserelin induced a significant elevation in HDL-C (by 31.4%), in HDL2-C (24.6%) and in HDL3-C (45.7%) but no significant change in LDL-C or in ApoA-1 and ApoB. By contrast, danazol caused significant diminutions in HDL-C (23.9%), HDL2-C (56.6%) and ApoA-1 (35.6%). Moreover, danazol increased LDL-C (10.5%) and ApoB (29.0%, P less than 0.05). The lipoprotein changes during goserelin had a favourable effect on the atherogenic index (cholesterol/HDL-C) and ApoA-1/ApoB ratio whereas those of danazol had opposite effects. These changes reverted 2 months after danazol while HDL was still elevated after goserelin.

CONCLUSIONS

In relation to cholesterol, goserelin is a safe medication. The significance of temporary adverse changes in cholesterol fractions due to danazol is still unknown.

Time-related effects of gonadotropin-releasing hormone analog treatment in experimentally induced endometriosis in the rat

The purpose of our study was to characterize the time-dependent effect of gonadotropin-releasing hormone analog (GnRH-a) therapy on endometriosis explant using the rat model. Endometriosis was induced in 60 mature female rats. One group of treated animals as well as controls were killed at 2, 4, 6 and 8 weeks of treatment at which time the explant was evaluated. Explant volume was significantly reduced in all treatment groups, an effect that was more significant in animals treated for greater than or equal to 4 weeks compared with those treated for only 2 weeks. We conclude that GnRH-a treatment caused gradual regression of endometrial explant that was effectively complete by 4 weeks of treatment. We further conclude that this experimental model may be useful in the evaluation of other modes of endometriosis therapy.

Gonadotrophin releasing hormone agonist (buserelin) in the treatment of endometriosis: changes in the extent of the disease and in CA 125 serum levels after 6-month therapy

Twenty-two women with endometriosis were treated with the luteinizing hormone-releasing hormone (LHRH) agonist buserelin for 6 months. At second-look laparoscopy the mean score of endometriosis had decreased from 23.1 (SD 17.0) to 17.2 (SD 20.2) (P less than 0.05). CA 125 serum levels decreased from 38.4 (SD 32.2) U/ml at diagnosis to 15.5 (SD 7.0) at second look (P less than 0.005). CA 125 levels correlated at diagnosis with total score of endometriosis (P less than 0.05) and with active score of endometriosis (P less than 0.05), but not with the adhesion score. CA 125 levels were not correlated with endometriosis scores at second look laparoscopy, thus suggesting that mechanisms other than the change in the extent of the disease may be involved in the CA 125 decrease during therapy. CA 125 levels may therefore not be a reliable indicator for monitoring the efficacy of LHRH agonist treatment of endometriosis.

Elevated peritoneal fluid luteinizing hormone and prolactin concentrations in infertile women with endometriosis

In this study, we compared (Mann-Whitney U-test) the peritoneal fluid FSH, LH and PRL levels, measured by RIA, at the follicular and luteal phases of the menstrual cycle in women with (n = 43; age 25-44 years) and with no evidence of endometriosis (n = 35; age 25-39 years) who were considered as controls. Both follicular and luteal phase FSH concentrations of women with endometriosis were not statistically different (n = 22 vs 18; 0.32-5.8 vs 0.50-8.2 IU/l, P = 0.247; n = 13 vs 14; 0.6-6.5 vs 0.66-6.7 IU/l, P = 0.604) compared to their respective controls. In contrast to FSH, the concentrations of LH at follicular (n = 19 vs 17; 3.1-34.2 vs 2.3-12.2 IU/l, P = 0.01) and luteal (n = 17 vs 15; 2.1-95.4 vs 1.3-17.9 IU/l, P = 0.02) phases of the test group was significantly elevated at both phases of the cycle. With respect to differences in PRL concentrations at follicular phase no significant change (n = 21 vs 16; 1030-5800 vs 1305-4650 mIU/l; P = 0.255) was observed. The greatest difference in luteal PRL concentrations (P = 0.007) was obtained between the women with endometriosis and controls (n = 17 vs 17; 1895-8600 vs 1041-5000 mIU/l). The results suggest that disordered synchronization of neuroendocrine mechanisms controlling LH and PRL may be the underlying abnormality causing infertility in our group of patients with endometriosis.

Endometriosis-associated infertility treated by long-term gonadotropin-releasing hormone agonist administration and assisted fertilization

Two patients with long-lasting infertility associated with moderate and severe symptomatic endometriosis were treated with long-term GnRH-agonist suppression of ovarian function. Both patients were relieved of their endometriosis-related abdominal pains during the first treatment month. After an additional treatment period of 3 to 5 months, assisted fertilization was performed, resulting in an ongoing pregnancy for both patients.

Endometriosis and infertility

The relationship of endometriosis, the most common benign gynaecological disease during reproductive life, to infertility is generally ill understood. The association between infertility and minimal to mild endometriosis, when no anatomical defect is evident, may be explained by the following possible mechanisms: alternations in peritoneal fluid (macrophages - immunoglobulins, Interleukin-1, protease inhibitors, prostanoids, an ovum capture inhibitor), ovulatory dysfunctions (anovulation, LUF syndrome), luteal phase defect, disturbed implantation, and spontaneous abortion. These possibilities are discussed. The latest prospective controlled studies offer strong evidence that endometriosis per se is not a direct cause of infertility. On the other hand, the disease usually deteriorates if not treated, and therefore medical or surgical interventions are often needed when expectant treatment or other infertility therapies, e.g., ovulation induction, fail to result in pregnancy. Women with minimal to mild endometriosis only should be diagnosed as having unexplained infertility, which today may be treated by in vitro fertilization.

Buserelin. A review of its pharmacodynamic and pharmacokinetic properties, and clinical profile

The gonadotrophin releasing hormone (GnRH) [luteinising hormone-releasing hormone (LHRH); gonadorelin] agonist buserelin is a promising new agent in the treatment of a variety of disorders in gynaecology and andrology, paediatrics and oncology. While a single dose of buserelin stimulates the release of pituitary gonadotrophins, multiple doses produce reversible pituitary desensitisation, and this specific blockade of gonadotrophin support to the gonads provides the basis for the drug's efficacy in conditions dependent on sex hormone secretion. Thus, buserelin provides comparable efficacy to orchidectomy or high dose estrogens in the treatment of hormone-sensitive prostate cancer and exhibits a lower incidence of adverse effects. During the early phase of treatment it may be particularly useful in combination with antiandrogens. Buserelin also appears promising in hormone-sensitive premenopausal breast cancer. Extensive studies have proven the value of buserelin in endometriosis, where it produces a transient remission with gradual recurrence of the disease on cessation of treatment. Surgical intervention is necessary in severe disease after buserelin-induced involution of the lesions. In patients with uterine leiomyoma, preliminary data suggest that buserelin may be beneficial in rendering surgery more conservative by reducing fibroid size, although it appears unlikely to preclude surgical intervention. The use of buserelin to induce a state of reversible hypogonadotrophism before administration of exogenous gonadotrophins is a promising strategy in the treatment of infertility associated with polycystic ovary syndrome and other conditions of infertility with underlying ovarian dysfunction; such a strategy also clearly enhances the efficiency of in vitro fertilisation programmes. Initial studies suggest its potential usefulness as a female contraceptive when administered intermittently in conjunction with a progestogen. Buserelin represents a first-line treatment of central precocious puberty. In endometriosis the adverse effect profile of buserelin is generally favourable, with hypoestrogenic effects such as hot flushes and vaginal dryness, and decreased libido, predominating. There is no apparent detrimental effect on lipid metabolism. The potential for adverse hypoestrogenic effects on bone mineral content with long term administration remains to be clarified. Thus, the GnRH agonist buserelin represents an advance in the treatment of a variety of gynaecological and andrological as well as paediatric and oncological conditions, infertility and other sex-hormone dependent conditions, with a low incidence of adverse treatment effects.

Endocrine, metabolic, and clinical effects of gestrinone in women with endometriosis

The effect of oral gestrinone, 2.5 mg twice weekly for 6 months, was studied in 11 women with mild or moderate endometriosis laparoscopically confirmed. The mean laparoscopic score decreased from 17.18 to 9.09 (P greater than 0.005). Painful symptoms were relieved in all patients within 2 months from start of therapy. Gonadotropins, prolactin (PRL) 17 beta-estradiol (17 beta-E2), estrone (E1), progesterone (P), androstenedione (A), and dehydroepiandrosterone sulfate (DHEA-S) remained in the follicular phase range. Total testosterone (TT) and sex hormone-binding globulin (SHBG) decreased, whereas free testosterone (FT) slightly increased. Metabolic studies showed a decrease of total triglycerides, very low-density lipoprotein (VLDL) triglycerides, and high-density lipoprotein (HDL) and VLDL cholesterol, parallel to the decrease of associated apoproteins. Low-density lipoprotein cholesterol and apoprotein B increased during therapy. The results suggest that gestrinone possesses antiestrogenic, androgenic, and progestigenic effects at therapeutic dosages both by acting on central and peripheral steroid receptors. For its efficacy and good tolerance, gestrinone may be considered an option for treating endometriosis.

Metabolic changes during medical treatment of endometriosis: nafarelin acetate versus danazol

In this double-blind study of changes in plasma lipid and lipoprotein concentrations during 6-month medical treatment of endometriosis, 53 patients were randomly assigned to one of four treatment schedules: danazol, 800 mg/day (n = 10); danazol, 600 mg/day (n = 8); intranasal nafarelin acetate, 800 micrograms/day (n = 10); or intranasal nafarelin acetate, 400 micrograms/day (n = 25). Plasma levels of triglycerides, cholesterol, and low-density lipoprotein, very low-density lipoprotein, and high-density lipoprotein cholesterol fractions were obtained before, during, and 1 month after treatment. High-density lipoprotein2 and high-density lipoprotein3 cholesterol concentrations were measured in selected patients. Body weight was also followed. The drugs were equally effective in achieving symptomatic relief and laparoscopically demonstrated resolution of endometriosis but differed significantly in their effects on lipid concentrations. Nafarelin acetate had no adverse effects on serum lipoprotein concentrations, whereas danazol significantly decreased high-density lipoprotein cholesterol (p less than 0.01), as well as the high-density lipoprotein2 subfraction (p less than 0.05), and increased low-density lipoprotein cholesterol (p less than 0.01). Danazol significantly increased body weight (p less than 0.01), whereas nafarelin did not.