Modern medical management of endometriosis

The use of gonadotropin releasing hormone analogues in adolescent and young patients with endometriosis

PURPOSE OF REVIEW

Endometriosis is increasingly being recognized and diagnosed in adolescents. As a result of this earlier diagnosis, treatment with agents like gonadotropin releasing hormone agonist (GnRHa) begins earlier and may last longer. Long-term effects of GnRHa treatment for endometriosis are of concern when treating adolescents.

RECENT FINDINGS

GnRHas are used for adolescents with surgically confirmed endometriosis. GnRHa treatment is effective for pain reduction, but is associated with menopausal symptoms and decreases in bone density. Different regimens of hormonal add-back therapy have been studied in adults to attempt to prevent these side-effects.

SUMMARY

GnRHa therapy is a highly effective, nonsurgical treatment option for many adolescents with endometriosis, but is accompanied by side-effects of bone loss and menopausal symptoms. Side-effects may be decreased by introducing appropriate add-back therapy. Monitoring of bone density by DXA is recommended for prolonged use of GnRHa in adolescents.

Treatment of endometriosis with local acetylsalicylic acid injection: experimental study in rabbits

The objective of the present study was to estimate the effects of introduction of acetylsalicylic acid solution into peritoneal implants in autologous endometrium as a method for treating endometriosis. Forty adult female rabbits were subdivided into 4 groups of 10 rabbits each, and endometriosis was induced via autotransplantation of endometrial fragments into the peritoneal cavity. At 30 days after induction of endometriosis, all animals were randomly assigned to 1 of 2 protocols. In protocol 1, animals were evaluated at 24 hours after treatment; group 1 (control) received physiologic solution, and group 2 received acetylsalicylic acid. In protocol 2, animals were evaluated at 10 days after treatment, group 3 (control) and group 4 received acetylsalicylic acid. After measuring the lesion, the endometriotic focus was removed and prepared for mounting on slides for histologic analysis. Imaging software was used for analysis of the total remaining area of endometrial tissue. The affected area in acetylsalicylic acid-treated animals was smaller than that in control animals at 24 hours and 10 days after treatment; a significant difference was found between control and treated groups (p < .001). Statistical analysis comparing protocols 1 and 2 demonstrated no differences between controls groups or acetylsalicylic acid groups (p = .30), and no differences between times (p = .75). Acetylsalicylic acid solution led to less growth (or higher involution) of endometrial implants. Acetylsalicylic acid injected directly into endometriotic foci was effective in their destruction. This presents new perspectives for treatment of endometriosis and for clinical applications based on further clinical studies.

Role of melatonin in regulating matrix metalloproteinase-9 via tissue inhibitors of metalloproteinase-1 during protection against endometriosis

Endometriosis is a gynecological disease of women and plausibly regulated by matrix metalloproteinases (MMPs). However, mechanisms of alterations in MMPs during endometriosis remain unclear. Human endometriotic tissues possessing varying degrees of severity were examined for expression of MMPs and tissue inhibitors of metalloproteinase (TIMP)-1. In addition, endometriosis was generated in mice and endometriotic tissues were tested for MMP-9 activity. Results show significant upregulation of secreted and synthesized proMMP-9 activity with duration and severity of endometriosis. Along with upregulation of activity, the expression of proMMP-9 was found increased while TIMP-1 expression followed an inverse trend. The effect of melatonin, a major secretory product of the pineal gland, on endometriosis was examined in preventive and therapeutic models in mice. The results show that melatonin arrested lipid peroxidation and protein oxidation and downregulated proMMP-9 activity and expression in a time and dose-dependent manner while protecting and regressing peritoneal endometriosis. Moreover, the attenuated activity and expression of proMMP-9 were associated with subsequent elevation in the expression of TIMP-1. Our study reveals for the first time the role of melatonin in arresting peritoneal endometriosis in mice and a novel marker, expression ratio of proMMP-9 versus TIMP-1, was identified for assessing severity and progression of endometriosis.

Toward gene therapy of endometriosis: adenovirus-mediated delivery of dominant negative estrogen receptor genes inhibits cell proliferation, reduces cytokine production, and induces apoptosis of endometriotic cells

OBJECTIVE

To use dominant negative mutants of estrogen receptor genes delivered to endometriosis cells via an adenovirus vector (Ad-DN-ER) to abrogate estrogen action on these cells.

DESIGN

Experimental in vitro study.

SETTING

University research laboratory.

PATIENT(S)

Patients with ovarian endometriomas provided endometriotic cells, and patients with uterine prolapse or subserous leiomyoma provided control endometrial cells.

INTERVENTION(S)

Transfection of endometriotic cells by dominant negative estrogen receptor genes via adenovirus vector (Ad-DN-ER).

MAIN OUTCOME MEASURE(S)

The main outcome measures were cellular proliferation, cytokine production, and induction of apoptosis in endometriotic cells.

RESULT(S)

Coxsackievirus-adenovirus receptor mRNA expression and adenovirus transduction efficiency were significantly higher in endometriotic than normal endometrial cells. Ad-DN-ER-treated endometriotic cells, as compared with control virus-treated cells, showed cell rounding and detachment (cell death), a 72% reduction in the number of viable cells 5 days after transduction, significantly less production of monocyte chemotactic protein-1 (7.8 +/- 0.5 vs. 152.8 +/- 1.9 pg/mL, respectively), vascular endothelial growth factor (356.2 +/- 11.6 vs. 997.3 +/- 16.5 pg/mL, respectively), and interleukin-6 (268.7 +/- 2.6 vs. 414.5 +/- 3.6 pg/mL, respectively), and a significantly higher percentage of apoptotic cells (51.2 +/- 7.8 vs. 23.8 +/- 1.7, respectively).

CONCLUSION(S)

An adenovirus can effectively transfect endometriotic cells in vitro. The DN-ER delivered to endometriotic cells via an adenovirus decreases cell proliferation, induces apoptosis, and decreases cytokine production. Adenovirus-mediated gene therapy may represent a potential therapeutic option for endometriosis in the future.

Effect of a statin on an in vitro model of endometriosis

OBJECTIVE

To determine the inhibitory effect of a statin on angiogenesis in a three-dimensional (3-D) culture of human endometrial fragments in vitro. Angiogenesis has been proposed as an important mechanism in the pathogenesis of endometriosis, and statins (3-hydroxy-3-methylglutaryl-coenzyme A reductase inhibitors) have been shown to have anti-inflammatory and anti-angiogenic activity.

DESIGN

Experimental in vitro study of human endometrial biopsies and 3-D culture in fibrin matrix.

SETTING

Research laboratory at a university-affiliated infertility center.

PATIENT(S)

Forty-six normal ovulating women undergoing infertility treatment.

INTERVENTION(S)

Endometrial samples obtained from the fundus of the uterine cavity were minced, and the fragments were placed in a three-dimensional fibrin matrix culture system.

MAIN OUTCOME MEASURE(S)

Presence or absence of proliferation of stromal cells and invasion of the fibrin matrix, presence or absence of vessel sprouting, and immunohistochemical characterization of cellular components.

RESULT(S)

During the 1st week of culture, invasion of stromal cells into the fibrin matrix occurred in the control group and in some wells outgrowths were observed. After 2 weeks, endometrial glands were observed in the outgrowths at a distance from the main tissue and were growing in conjunction with new vessel formation until the end of culture period. A concentration-dependent effect of lovostatin was seen on cell growth and angiogenesis in the experimental groups. In the presence of 5 and 10 microM of statin, angiogenesis was abolished, and cell proliferation was inhibited. In the presence of 1 microM of lovastatin, angiogenesis was reduced, but cell proliferation was not affected.

CONCLUSION(S)

The statins were shown to be effective in inhibiting the mechanisms of cell proliferation and angiogenesis in an experimental model for the development of endometriosis-like tissue.

Medical management of endometriosis

Current approved medical therapies for endometriosis rely on drugs that suppress ovarian steroids and induce a hypoestrogenic state, which determines the atrophy of the ectopic endometrium. Gonadotropin-releasing hormone analogs such as danazol, progestogens and estrogen-progestin combinations have all proven effective in relieving pain and reducing the extent of endometriotic implants. However, symptoms often recur after discontinuation of therapy and hypoestrogenism-related side effects limit the long-term use of most medications. Recently, knowledge of the pathogenesis of endometriosis, particularly at the molecular level, has grown substantially, providing a rational basis for the development of new drugs with precise targets that may be safely administered over the long term.

Extragenital endometriosis--a clinicopathological review of a Glasgow hospital experience with case illustrations

The clinicopathological characteristics of 34 cases of extragenital endometriosis (mean age 33.74) presenting to surgeons over a 9-year period at Glasgow Royal Infirmary were reviewed. A total of 379 cases of endometriosis were diagnosed by histology during the period, giving an 8.9% prevalence of extragenital manifestations. Eleven (32.3%) cases were in the intestinal tract, two (5.9%) in the urinary tract and 21 (61.8%) were in other sites, including pfannenstial scar, inguinal canal, umbilicus and perineum; 52.9% presented to gynaecologists and mean time to diagnosis was 24.54 months (CI: 13.2 - 35.8). Pain was the most common presentation in 76.5% but this was cyclical, reported in only 41.2%. Palpable mass was found in 41.2%, especially in pfannenstial scar (26.5%), suggesting iatrogenic cause. Histology remains the cornerstone of diagnosis and several of the case histories describe delay and diagnostic confusion. Endometriosis is rarely fatal, but continues to challenge patients and clinicians in all specialities in presentation and diagnosis.

Intestinal endometriosis: the great masquerader

Chronic symptoms of abdominal pain and irregular bowel habits in women evoke a broad differential diagnosis including irritable bowel syndrome, infection, malabsorption, and inflammatory bowel disease. Endometriosis, a common disorder in young women that can involve the intestinal tract, deserves consideration as well. Intestinal endometriosis is typically asymptomatic; however, when symptoms occur, they can mimic those of irritable bowel syndrome. Identifying intestinal endometriosis can be challenging, but historical points and key clinical features aid in diagnosis.

Endometriosis and Reproductive Disorders

The classic concept of endometriosis as a cause of infertility is challenged. Traditionally, both surgical and medical therapy have focused on alleviation of symptoms, prevention of disease progression, and promotion of fertility. In spite of significant developments in medical and surgical approaches, the optimal therapy for treating endometriosis-associated infertility has yet to be established. The relationship between prevalence of fecundity and stage of the disease was studied according to the type of management. Of 151 women who were consecutively proved by laparoscopy to have endometriosis stage I and II, operative laparoscopy was performed in 49, medical treatment in 59, and expectant management in 43 cases. During a 24-month period, the cumulative pregnancy rates were 36.7%, 30.5%, and 20.9%, respectively. Survival analysis over the 20 weeks of pregnancy showed that the probability of carrying the pregnancy beyond this week was 30.6%, 25.4%, and 16.2%, respectively. Of 64 patients with advanced disease, 34 (53%) became pregnant during the 2-year follow-up period. A significantly increased pregnancy rate was found for the first year as compared to the second (76% vs. 24%). The existence of adhesions affected adversely the outcome of the treatment when early achievement of pregnancy is considered. Diagnosis and treatment of endometriosis was beneficial for the infertile women. Laparoscopic surgery seems to be the best treatment in these cases, as it increases the fecundity and involves minimal risk.

Three-dimensional in vitro culture of endometrial explants mimics the early stages of endometriosis

OBJECTIVE

To reproduce the earliest phases of endometriosis using a new in vitro model in which cells from a cultured endometrial fragment can proliferate, invade, reconstitute new endometrial-like tissue, and generate blood vessels.

DESIGN

Experimental in vitro study.

SETTING

A hospital-based academic research institute.

PATIENT(S)

Five normal ovulating women undergoing surgery for various benign gynecological indications.

INTERVENTION(S)

Endometrial samples obtained from the fundus of the uterine cavity were placed in a three-dimensional fibrin matrix culture system.

MAIN OUTCOME MEASURE(S)

Degree of proliferation of stromal cells and invasion of the fibrin matrix, gland, and stroma formation, vessel sprouting, and immunohistochemical characterization of various cellular components.

RESULT(S)

During the first week of culture, an endometrial cell outgrowth was observed from the original fragments in 120 of 144 wells (83.3%). Subsequently, cell outgrowths could be quantified in 132 (91.6%), 129 (89.5%), and 127 (88.1%) of the wells after 15, 60, and 90 days, respectively. An invasion of the matrix by the human endometrial cells led to the formation of tubular structures that coalesced into tissue, architecturally resembling endometrium and in which the glands were immunohistochemically positive for cytokeratin. New capillaries, immunohistochemically positive for CD31 and vimentin, sprouted from the endometrial outgrowths at the beginning of the fifth week of culture.

CONCLUSION(S)

These data show that cells from endometrial explants can proliferate and invade a fibrin matrix in vitro generating new glands, stroma, and vessels consistent with endometriosis. The three-dimensional fibrin matrix used in the present study provides an opportunity to observe the earliest biological events of endometriosis in a quantifiable way.

A pilot study of the use of low dose human menopausal gonadotropin in ovulation induction

OBJECTIVE

To evaluate the clinical efficacy of a combined regimen of follicle stimulating hormone (FSH) and low dose human menopausal gonadotropin (hMG) following GnRH agonist ultralong protocol in controlled ovarian hyperstimulation (COH) for in vitro fertilization and embryo transfer (IVF-ET).

STUDY DESIGN

IVF-ET was performed on 45 patients who had uterine or peritoneal factors, such as moderate to severe endometriosis, adenomyosis, or uterine myoma. The patients were randomized into two groups after the administration of long-acting GnRH agonist 2-4 times within a 4-week interval; highly purified FSH (FSH-HP) and hMG (Group A, n=26), FSH-HP only (Group B, n=19). hMG was administered at a fixed-dose of 75IU per day and the dose of FSH-HP was adjusted according to the patient's individual response. The results of COH and IVF-ET were assessed and compared between the two groups.

RESULTS

Serum estradiol (E2) level on hCG day was significantly higher in Group A (1418.2+/-920.2 pg/ml, mean+/-S.D.) than in Group B (678.4+/-457.8 pg/ml) (P<0.05). The clinical pregnancy rate and implantation rate tended to be higher in Group A than in Group B; 23.1% (6/26) versus 10.5% (2/19), 11.0% (9/82) versus 4.6% (3/65).

CONCLUSION

In COH for IVF-ET using GnRH agonist ultralong protocol, the combined treatment of FSH-HP and low dose hMG showed a higher serum E2 level when compared with treatment with FSH-HP alone.

In vivo properties of an anti-GnRH Spiegelmer: an example of an oligonucleotide-based therapeutic substance class

Spiegelmers are high-affinity l-enantiomeric oligonucleotide ligands that display high resistance to enzymatic degradation compared with d-oligonucleotides. The target binding properties of Spiegelmers can be designed by an in vitro-selection process starting from a random pool of oligonucleotides. Applying this method, a Spiegelmer with high affinity (K(D) = 20 nM) for the peptide hormone, gonadotropin-releasing hormone (GnRH) was isolated. The Spiegelmer acts as an antagonist to GnRH in Chinese hamster ovary cells stably expressing the human GnRH receptor, and its activity is unchanged by linking to 40-kDa polyethylene glycol. In a castrated rat model the Spiegelmer further demonstrated strong GnRH antagonist activity, which is more pronounced and persists longer with the polyethylene glycol-linked derivative. Furthermore, in rabbits the anti-GnRH Spiegelmer was shown to have a very low, possibly negligible immunogenic potential. These studies suggest that Spiegelmers could be of substantial interest in the development of new pharmaceutical approaches against GnRH and other targets.

Gonadotropin-releasing hormone agonist treatment for endometriosis of the rectovaginal septum

OBJECTIVE

This study was undertaken to evaluate the effectiveness of a 6-month course of gonadotropin-releasing hormone agonist treatment for patients with symptomatic endometriosis of the rectovaginal septum.

STUDY DESIGN

Fifteen patients with rectovaginal endometriosis and moderate to severe pain symptoms were the subjects of the study. None of these patients had either clinical or objective evidence of ovarian endometriosis, nor was there evidence of any obstructive lesions of the intestine or ureters. All patients were given leuprolide acetate depot at 3.75 mg, 1 ampule intramuscularly every 28 days, and treatment had a planned duration of 6 months. Follow-up evaluations were set every 2 months during the treatment phase and every 3 months thereafter until the completion of 1 year after discontinuation of medical therapy. At each follow-up visit pain symptoms were recorded, and clinical exploration, transvaginal ultrasonography, and transrectal ultrasonography were performed.

RESULTS

Two patients stopped the treatment early after the second and fourth leuprolide doses; in both cases the reason was persistence of pain, and both requested a surgical solution. The other 13 patients showed a marked improvement with respect to pain during the 6-month treatment course but had early pain recurrence after drug suspension; 11 of them required further treatment within the first year of follow-up. The failure rate of gonadotropin-releasing hormone agonist therapy to produce 1-year pain relief after treatment discontinuation was 87% (13/15) on an intent-to-treat basis. The endometriotic lesions showed a slight but significant reduction in size during therapy but had returned to the original volume within 6 months after cessation of the gonadotropin-releasing hormone analog treatment.

CONCLUSION

Our results suggest that gonadotropin-releasing hormone analogs should not be considered a real therapeutic alternative to surgical treatment for patients with symptomatic endometriosis of the rectovaginal septum, except possibly in a limited and unpredictable number of cases.

An evidence-based medicine approach to the treatment of endometriosis-associated chronic pelvic pain: placebo-controlled studies

OBJECTIVE

Use an evidence-based medicine (EBM) approach to evaluate the evidence regarding efficacy of treatment of endometriosis-associated chronic pelvic pain (CPP) in placebo-controlled randomized clinical trials (RCT).

DESIGN

Review of six randomized, controlled trials (Canadian Task Force classification I).

SETTING

University of Rochester School of Medicine and Dentistry. Patients. Three hundred eighty-one women with endometriosis enrolled in placebo-controlled randomized clinical trials. Intervention. A MEDLINE search of published medical articles from January 1976, to January 1998.

MEASUREMENTS AND MAIN RESULTS

Six placebo-controlled randomized clinical trials were found that addressed the treatment of pelvic pain associated with endometriosis and met validity criteria; one was a study of surgical treatment, two of medical therapies, and three of combined surgical and medical treatments. They clearly show that laparoscopic surgery and medical treatment with medroxyprogesterone acetate, danazol, or nafarelin are more effective than placebo. Evidence for efficacy of leuprolide acetate is weaker. At 6 months, absolute decreases in pain scores are quite similar with surgical or medical treatment. Medical therapy after surgical treatment significantly reduced pain, but six months after it was stopped there was no difference between women treated and not treated postoperatively.

CONCLUSIONS

Although either surgical or medical treatment of endometriosis in women with CPP is clearly indicated, pain relief of 6 or more months' duration can be expected in only 40 to 70% of women with endometriosis-associated CPP.

Endometrial ability to implant in ectopic sites can be prevented by interleukin-12 in a murine model of endometriosis

Immune dysfunctions in endometriosis are widely documented but the effectiveness of immunotherapies for the management of the disease is still debated. Progress in this field has also been limited by the lack of an appropriate animal model of the disease. In this study, we created a model of endometriosis in immunocompetent mice to verify the ability of endometrium to implant in ectopic sites and to investigate the potential application of the cytokine interleukin (IL)-12 in preventing this ectopic implantation. Endometriotic lesions were induced in both C57BL/6 and BALB/c mice by inoculating syngenic endometrial fragments through a small laparotomic incision into the peritoneal space. All the animals challenged with syngenic endometrium showed evidence of peritoneal endometriosis at 3 weeks. Histologically, endometriotic lesions consisted of cystic endometrial glands surrounded by a stroma. Intraperitoneal injection of IL-12 was able to reduce total weight and total surface area of endometriotic lesions respectively of 77 and 61% in C57BL/6 and of 42 and 28% in BALB/c mice. These results demonstrate that IL-12 is able to induce a significant prevention of ectopic endometrial implantation in an in-vivo model of endometriosis. These findings support the possibility of using the immune system to generate novel therapies for the management of the disease.

Endometriosis and a paraovarian cyst in a rhesus macaque

We describe endometriosis in an aged rhesus macaque. There was a large mass and a related paraovarian cyst, typical of the disease. Endometriosis is a common finding in nonhuman primate. In this report, we also review the pathophysiology of the disease and summarize the historical and more recent relevant literature. Given the frequency of endometriosis in the rhesus monkey and the long-life spans (15-30 years) of nonhuman primates in captivity, endometriosis should be suspected in animals displaying the earliest signs of the disease: anorexia, dysmenorrhea, menorrhagia, irregular menstrual cycles, or infertility. Despite recent advances in the diagnosis and therapeutic strategies for endometriosis in women, the disease remains a significant cause of morbidity and ultimately, a cause of mortality, in the older nonhuman primate.

Today's treatments: medical, surgical and in partnership

OBJECTIVE

To provide an overview of the medical, surgical and combined therapy options for endometriosis.

RESULTS

Available medical options include danazol, progestogens, gestrinone, oral contraceptive agents, analgesics and gonadotropin-releasing hormone (GnRH) agonists. Used in the short-term, most of these agents relieve pain in a large proportion of patients and produce disease regression, however, they do not prevent recurrence, and are associated with side-effects. However, few data confirm any benefit of short-term medical therapy on fertility. One of the most promising medical approaches appears to be GnRH agonists with add-back hormone replacement therapy. Surgery may relieve pain, eradicate visible disease and improve fertility. A combined approach may facilitate surgery and relieve pain, although any fertility benefit is as yet unproven.

CONCLUSION

Both short-term medical treatment and surgery relieve endometriosis-associated pain and decrease endometriotic implants. However, all approaches have side effects which must be balanced against the benefits when defining suitable treatment for a particular patient.

Other medical management of uterine fibroids

Several medicines are emerging with the potential to treat symptomatic uterine fibroids. Anti-progesterone compounds seem particularly promising. These drugs have been widely used for nearly 20 years and are known to be safe; medical politics have prevented their proper investigation for uterine fibroids. In particular, the value of mifepristone, 50 mg per day for 3 months, seems particularly promising. Further investigation is clearly warranted for this medicine. Several anti-oestrogen compounds have recently become available and may also be useful for the medical treatment of symptomatic uterine fibroids. This includes the possibility of the use of selective oestrogen receptor modulators as well as the prospect of the use of pure anti-oestrogens. On a longer time frame, inhibitors of angiogenesis may be useful. These medicines would act upon the blood supply to uterine fibroids. Physicians also have an obligation to investigate scientifically any promising naturopathic treatment that appears to have possible activity for symptomatic fibroids.