Endometriosis: cost estimates and methodological perspective

Melatonin treatment results in regression of endometriotic lesions in an ooferectomized rat endometriosis model

OBJECTIVE

We aimed to determine the effects of melatonin treatment on endometrial implants in an oopherectomized rat endometriosis model.

MATERIAL AND METHODS

This study is a prospective, randomised, controlled experimental study. It was carried out at the Experimental Research Center of Yeditepe University (YUDETAM). Twenty-two, female, non-pregnant, nulligravid Spraque-Dawley albino rats were included in our study. Endometriosis was surgically induced in oopherectomized rats. Rats were randomised into two groups: control group and melatonin group. In the melatonin group, rats were treated with melatonin (20 mg/kg/day) for two weeks. After the operations were performed to assess the regression of the endometriotic lesions, melatonin treatment was stopped. At the end of the sixth week necropsies were performed to assess the rate of recurrence. The volume and histopathological scores of endometriotic foci were examined.

RESULTS

Volumes of the endometriotic lesions significantly decreased in the melatonin group. Also, when the melatonin group was analysed within itself, endometriotic lesion volumes decreased and histopathological scores increased significantly.

CONCLUSION

Melatonin causes regression of the endometriotic lesions in rats and improvement in their histopathological scores.

Improvement in chronic pelvic pain after gonadotropin releasing hormone analogue (GnRH-a) administration in premenopausal women suffering from adenomyosis or endometriosis: a retrospective study

The aim of this study was to evaluate the improvement in catamenial chronic pelvic pain (CPP) after Gonadotropin Releasing Hormone analogue (GnRH-a) administration in women affected by adenomyosis or endometriosis. We retrospectively analysed clinical data of 63 premenopausal women with clinical suspect of adenomyosis (15 women, Group A) or endometriosis (48 women, Group B), which received GnRH-a in order to reduce CPP intensity during the time on surgery waiting list. Main outcome measures were variation of CPP intensity, numbers of days requiring analgesics and lost work productivity before and three months after GnRH-a administration. Compared to baseline, a significant decrease in CPP intensity (p < 0.05) was observed in both groups, even if this reduction was significantly higher in Group A than in Group B (p < 0.001). In both groups, moreover, a significant reduction in number of days requiring analgesics (p < 0.05) and lost work productivity (p < 0.05) was detected. In conclusion, GnRH-a administration in women with clinical suspect of adenomyosis induces a greater reduction in CPP when compared to women with endometriosis, thus representing a potential ex adiuvantibus criteria, helping TV-US in the clinical diagnosis of adenomyosis.

A novel role of the Sp/KLF transcription factor KLF11 in arresting progression of endometriosis

Endometriosis affects approximately 10% of young, reproductive-aged women. Disease associated pelvic pain; infertility and sexual dysfunction have a significant adverse clinical, social and financial impact. As precise disease etiology has remained elusive, current therapeutic strategies are empiric, unfocused and often unsatisfactory. Lack of a suitable genetic model has impaired further translational research in the field. In this study, we evaluated the role of the Sp/KLF transcription factor KLF11/Klf11 in the pathogenesis of endometriosis. KLF11, a human disease-associated gene is etiologically implicated in diabetes, uterine fibroids and cancer. We found that KLF11 expression was diminished in human endometriosis implants and further investigated its pathogenic role in Klf11-/- knockout mice with surgically induced endometriotic lesions. Lesions in Klf11-/- animals were large and associated with prolific fibrotic adhesions resembling advanced human disease in contrast to wildtype controls. To determine phenotype-specificity, endometriosis was also generated in Klf9-/- animals. Unlike in Klf11-/- mice, lesions in Klf9-/- animals were neither large, nor associated with a significant fibrotic response. KLF11 also bound to specific elements located in the promoter regions of key fibrosis-related genes from the Collagen, MMP and TGF-β families in endometrial stromal cells. KLF11 binding resulted in transcriptional repression of these genes. In summary, we identify a novel pathogenic role for KLF11 in preventing de novo disease-associated fibrosis in endometriosis. Our model validates in vivo the phenotypic consequences of dysregulated Klf11 signaling. Additionally, it provides a robust means not only for further detailed mechanistic investigation but also the ability to test any emergent translational ramifications thereof, so as to expand the scope and capability for treatment of endometriosis.

Cellular and molecular basis for endometriosis-associated infertility

Endometriosis is a gynecological disease characterized by the presence of endometrial glandular epithelial and stromal cells growing in the extra-uterine environment. The disease afflicts 10%–15% of menstruating women causing debilitating pain and infertility. Endometriosis appears to affect every part of a woman’s reproductive system including ovarian function, oocyte quality, embryo development and implantation, uterine function and the endocrine system choreographing the reproductive process and results in infertility or spontaneous pregnancy loss. Current treatments are laden with menopausal-like side effects and many cause cessation or chemical alteration of the reproductive cycle, neither of which is conducive to achieving a pregnancy. However, despite the prevalence, physical and psychological tolls and health care costs, a cure for endometriosis has not yet been found. We hypothesize that endometriosis causes infertility via multifaceted mechanisms that are intricately interwoven thereby contributing to our lack of understanding of this disease process. Identifying and understanding the cellular and molecular mechanisms responsible for endometriosis-associated infertility might help unravel the confounding multiplicities of infertility and provide insights into novel therapeutic approaches and potentially curative treatments for endometriosis.

Costs of endometriosis in Austria: a survey of direct and indirect costs

PURPOSE

The literature includes a wealth of medical data on endometriosis, but the economic significance of the condition has so far been neglected. An analysis of hospital costs for endometriosis in Austria was, therefore, carried out for economic purposes.

METHODS

Seventy-three patients with endometriosis were included in the study. A bottom-up approach was used to collect data on the average hospital costs of an endometriosis patient over a time period of 1 year. In addition, a prevalence approach was used that allows subsequent estimation of the total costs of endometriosis for the health-care system in Austria for that period. Retrospective questionnaire survey was conducted.

RESULTS

The average annual costs of one case of endometriosis are <euro>7,712, with <euro>5,605.55 attributable to direct costs and <euro>2,106.34 to indirect costs. This indicates an overall economic burden of <euro>328 million. In-patient care (45 %) and loss of productivity (27 %) were identified as the major cost factors. The patients themselves pay for 13 % of the costs (through out-of-pocket payments).

CONCLUSIONS

This study impressively demonstrates the financial burden on the economy and on each individually affected patient caused by the disease of endometriosis. The massive consumption of resources represents a high level of usage of the medical services provided. The question arises as to whether more timely diagnosis, followed by better-targeted treatment, might have the potential to reduce these costs. The overall economic burden of endometriosis in Austria is currently comparable with that of Parkinson's disease.

Research Resource: The Endometrium Database Resource (EDR)

In order to understand the biology of the endometrium and potentially develop new diagnostic tools and treatments for endometrial diseases, the highly orchestrated gene expression/regulation that occurs within the uterus must first be understood. Even though a wealth of information on endometrial gene expression/regulation is available, this information is scattered across several different resources in formats that can be difficult for the average bench scientist to query, integrate, and utilize. The Endometrium Database Resource (EDR) was created as a single evolving resource for protein- and micro-RNA-encoding genes that have been shown by gene expression microarray, Northern blot, or other experiments in the literature to have their expression regulated in the uterus of humans, mice, rats, cows, domestic pigs, guinea pigs, and sheep. Genes are annotated in EDR with basic gene information (eg, gene symbol and chromosome), gene orthologs, and gene ontologies. Links are also provided to external resources for publication/s, nucleic and amino acid sequence, gene product function, and Gene Expression Omnibus (GEO) phase expression graph information. The resource also allows for direct comparison of relative gene expression in different microarray experiments for genes shown in the literature to be differentially expressed in the uterus. It is available via a user-friendly, web-based interface and is available without charge or restriction to the entire scientific community. The EDR can be accessed at http://edr.research.bcm.edu.

A prospective cohort study of Vitamins B, C, E, and multivitamin intake and endometriosis

PURPOSE

Diet is a potentially modifiable risk factor for endometriosis. It has been hypothesized that vitamins C, E, and the B vitamins may influence factors involved in the pathogenesis of endometriosis, such as oxidative stress and steroid hormone metabolism. In this large, prospective cohort study, we examined the relation between intake of vitamins C, E, the B vitamins, and the use of multivitamin supplements and diagnosis of endometriosis.

METHODS

Data were collected from women in the Nurses' Health Study II between 1991 and 2005. Diet was assessed via food frequency questionnaire. Incidence rate ratios (RR) and 95% confidence intervals (CI) were estimated using time-varying Cox proportional hazards models.

RESULTS

A total of 1383 incident cases of laparoscopically-confirmed endometriosis were observed among 70,617 women during 735,286 person years of follow-up. Intakes of thiamine (B1) (RR = 0.84, CI = 0.72-0.99; P-value, test for linear trend [P] = 0.04), folate (B9) (RR = 0.79, CI = 0.66-0.93; P = 0.003), vitamin C (RR = 0.81, CI = 0.68-0.95; P = 0.02), and vitamin E (RR = 0.70, CI = 0.59-0.83; P<0.0001) solely from food sources were inversely related to endometriosis diagnosis. However, intakes of these nutrients from supplements alone were unrelated to endometriosis.

CONCLUSION

Thiamine, folate, vitamin C, and vitamin E from food sources are inversely related to endometriosis risk. Our results suggest that the protective mechanism may not be related to the nutrients themselves but rather other components of foods rich in these micronutrients or factors correlated with diets high in these vitamin-rich foods.

Intraoperative detection of subtle endometriosis: a novel paradigm for detection and treatment of pelvic pain associated with the loss of peritoneal integrity

Endometriosis is a common disease affecting 40 to 70% of reproductive-aged women with chronic pelvic pain (CPP) and/or infertility. The purpose of this study was to demonstrate the use of a blue dye (methylene blue) to stain peritoneal surfaces during laparoscopy (L/S) to detect the loss of peritoneal integrity in patients with pelvic pain and suspected endometriosis. Forty women with CPP and 5 women without pain were evaluated in this pilot study. During L/S, concentrated dye was sprayed onto peritoneal surfaces, then aspirated and rinsed with Lactated Ringers solution. Areas of localized dye uptake were evaluated for the presence of visible endometriotic lesions. Areas of intense peritoneal staining were resected and some fixed in 2.5% buffered gluteraldehyde and examined by scanning (SEM) electron microscopy. Blue dye uptake was more common in women with endometriosis and chronic pelvic pain than controls (85% vs. 40%). Resection of the blue stained areas revealed endometriosis by SEM and loss of peritoneal cell-cell contact compared to normal, non-staining peritoneum. Affected peritoneum was associated with visible endometriotic implants in most but not all patients. Subjective pain relief was reported in 80% of subjects. Based on scanning electron microscopy, we conclude that endometrial cells extend well beyond visible implants of endometriosis and appear to disrupt the underlying mesothelium. Subtle lesions of endometriosis could therefore cause pelvic pain by disruption of peritoneal integrity, allowing menstrual or ovulatory blood and associated pain factors access to underlying sensory nerves. Complete resection of affected peritoneum may provide a better long-term treatment for endometriosis and CPP. This simple technique appears to improve detection of subtle or near invisible endometriosis in women with CPP and minimal visual findings at L/S and may serve to elevate diagnostic accuracy for endometriosis at laparoscopy.

Costs of in-patient treatment for endometriosis in Germany 2006: an analysis based on the G-DRG-Coding

OBJECTIVE

The aim of this study was to estimate the financial burden of in-patients costs for endometriosis treatment in Germany in 2006.

METHODS

Data from a national in-patient database for women of reproductive age who were admitted for surgical treatment for endometriosis were analysed retrospectively. The number and type of hospital admissions involving surgical interventions for endometriosis were identified, and the costs of these hospitalizations to funding bodies in Germany were estimated using the diagnosis-related group reimbursement rates.

RESULTS

A total of 20,835 patients were admitted to hospital for endometriosis treatment in Germany in 2006 (1.27 per 1,000 women in reproductive age). The average cost per patient was estimated at 3,056.21 €. The total in-patient costs for endometriosis treatment in 2006 were estimated at 40,708,716.26 €. The surgical procedure most often performed in treating endometriosis was hysterectomy (in 24.70% of cases).

CONCLUSION

The burden of admissions and the economic impact associated with the inpatients treatment of endometriosis in Germany is substantial. The results presented here may enable those responsible in the field of medicine and health-care policy to improve the allocation of resources and manage expenses on a more sustained basis.

Economic burden of surgically confirmed endometriosis in Canada

OBJECTIVE

To estimate the societal economic burden of illness caused by surgically confirmed endometriosis in Canada in 2009, including direct health care costs, lost productivity, and lost leisure time costs.

METHODS

Using a cross-sectional design, direct health care resource use data were obtained from nine family physicians and nine gynaecologists from across Canada, who were experienced in the treatment of women with surgically confirmed endometriosis. Data on alternative treatments and health care providers, as well as work absenteeism, lost leisure time, and caregiver time were obtained from a convenience sample of 27 women with endometriosis treated at two gynaecology clinics in Alberta and Quebec. Unit costs were assigned to resource use items for treatment-seeking patients, and total costs for each resource use item were aggregated to estimate the societal costs of endometriosis in Canada in 2009, across all prevalent cases of surgically confirmed endometriosis.

RESULTS

The estimated mean annual societal cost of endometriosis was $5,200 per patient (95% CI $3,700 to $7,100), with lost productivity and lost leisure time costs accounting for 78%. Extrapolating these figures yields an estimated total annual cost to Canadian society of $1.8 billion (95% CI $1.3 billion to $2.4 billion) attributable to surgically confirmed endometriosis in Canada.

CONCLUSION

For some women, surgically confirmed endometriosis has a substantial negative impact that can result in suffering to the individual and her family, and lead to substantial productivity losses. Understanding the interplay between direct costs, lost productivity, and quality of life is critical for accurately identifying and evaluating effective treatments for this condition.

Tissue remodeling and nonendometrium-like menstrual cycling are hallmarks of peritoneal endometriosis lesions

We identified differentially expressed genes comparing peritoneal endometriosis lesions (n = 18), eutopic endometrium (n = 17), and peritoneum (n = 22) from the same patients with complete menstrual cycles using microarrays (54 675 probe sets) and immunohistochemistry. Peritoneal lesions and peritoneum demonstrated 3901 and 4973 significantly differentially expressed genes compared to eutopic endometrium, respectively. Peritoneal lesions significantly revealed no correlation with a specific menstrual cycle phase by gene expression and histopathology, exhibited low expressed proliferation genes, and constant levels of steroid hormone receptor genes. Tissue remodeling genes in cytoskeleton, smooth muscle contraction, cellular adhesion, tight junctions, and O-glycan biosynthesis were the most significant to lesions, including desmin and smooth muscle myosin heavy chain 11. Protein expression and location of desmin, alpha-actin, and h-caldesmon in peritoneal lesions discriminated between smooth muscle hyperplasia and metaplasia. Peritoneal lesions demonstrate no menstrual cycle phasing but constant steroid hormone receptor expression where a slow but steady growth is linked with tissue remodeling. Our study contributes to the molecular pathology of peritoneal endometriosis and will help to identify clinical targets for treatment and management.

Endometriosis and abdominal myofascial pain in adults and adolescents

Endometriosis and myofascial pain are common disorders with significant impact on quality of life. Increasingly, these conditions are being recognized as highly interconnected through processes that have been described for more than a century. This review is directed to this interconnection through a description of the relationships of endometriosis to proposed mechanisms of pain and chronic pain physiology; the clinical assessment of myofascial representations of this pain; and an approach to the management of these interconnected disorders.

Economic burden and quality of life of vulvodynia in the United States

OBJECTIVE

To explore the economic burden and quality of life of vulvodynia in the United States.

METHODS

We conducted a web-based survey from 2009 to 2010. Patients who responded to a National Vulvodynia Association advertisement completed the survey every month, recording their own costs and their employers' payments related to vulvodynia in the previous month. A total of 302 patients entered data for at least 1 month and among them, 97 patients had completed data for 6 months. We used multiple imputation to generate values for unobserved cost components. For insurance payments, we also extracted the average insurance payments for direct healthcare services relating to vulvodynia from a commercial insurance database. The total costs were disaggregated into direct healthcare costs, direct non-healthcare costs and indirect costs. We also assessed patients' quality of life by using Euro QOL 5 dimensions (EQ-5D) in a follow-up survey.

RESULTS

The total costs in 6 months were $8862.40 per patient, of which $6043.34 (68.19%) were direct healthcare costs, $553.81 (6.25%) were direct non-healthcare costs and $2265.25 (25.56%) were indirect costs. Based on the reported prevalence range of 3-7% in the US, our analysis yielded an annual national burden ranging from $31 to $72 billion in the US. However, the estimate should be viewed with caution as our study sample was non-probability. The average EQ-5D score was 0.74 ± 0.19 in vulvodynia patients.

CONCLUSION

Vulvodynia is associated with a huge economic burden to both individuals and society. It is also related to a relatively low quality of life.

New treatment strategies and emerging drugs in endometriosis

Introduction: Endometriosis, histologically defined as the presence of endometrium-like tissue - glands and stroma - that develops outside of the uterine cavity, is still an enigmatic disease responsible for pelvic pain and infertility. The current treatments of endometriosis are surgery and hormonal therapies that act by suppressing ovulation and/or directly on steroid receptors located in endometriotic lesions. Areas covered: New hormonal and non-hormonal therapies are being developed for the treatment of endometriosis-related pain. The authors review the state of advancement and the results of novel treatments studied in registered trials ( www.ClinicalTrials.gov ). Cellular signaling pathways activated in endometriotic cells, which constitute potential targets for future treatments, are also described. Expert opinion: Therapeutic research efforts should focus on identifying and testing substances capable of acting locally on the lesions themselves, without interfering with ovulation, in order to be efficacious on both pain symptoms and infertility.

Towards endometriosis diagnosis by gadofosveset-trisodium enhanced magnetic resonance imaging

Endometriosis is defined as the presence of endometrial tissue outside the uterus. It affects 10-15% of women during reproductive age and has a big personal and social impact due to chronic pelvic pain, subfertility, loss of work-hours and medical costs. Such conditions are exacerbated by the fact that the correct diagnosis is made as late as 8-11 years after symptom presentation. This is due to the lack of a reliable non-invasive diagnostic test and the fact that the reference diagnostic standard is laparoscopy (invasive, expensive and not without risks). High-molecular weight gadofosveset-trisodium is used as contrast agent in Magnetic Resonance Imaging (MRI). Since it extravasates from hyperpermeable vessels more easily than from mature blood vessels, this contrast agent detects angiogenesis efficiently. Endometriosis has high angiogenic activity. Therefore, we have tested the possibility to detect endometriosis non-invasively using Dynamic Contrast-Enhanced MRI (DCE-MRI) and gadofosveset-trisodium as a contrast agent in a mouse model. Endometriotic lesions were surgically induced in nine mice by autologous transplantation. Three weeks after lesion induction, mice were scanned by DCE-MRI. Dynamic image analysis showed that the rates of uptake (inwash), persistence and outwash of the contrast agent were different between endometriosis and control tissues (large blood vessels and back muscle). Due to the extensive angiogenesis in induced lesions, the contrast agent persisted longer in endometriotic than control tissues, thus enhancing the MRI signal intensity. DCE-MRI was repeated five weeks after lesion induction, and contrast enhancement was similar to that observed three weeks after endometriosis induction. The endothelial-cell marker CD31 and the pericyte marker α-smooth-muscle-actin (mature vessels) were detected with immunohistochemistry and confirmed that endometriotic lesions had significantly higher prevalence of new vessels (CD31 only positive) than the uterus and control tissues. The diagnostic value of gadofosveset-trisodium to detect endometriosis should be tested in human settings.

The burden of endometriosis: costs and quality of life of women with endometriosis and treated in referral centres

BACKGROUND

This study aimed to calculate costs and health-related quality of life of women with endometriosis-associated symptoms treated in referral centres.

METHODS

A prospective, multi-centre, questionnaire-based survey measured costs and quality of life in ambulatory care and in 12 tertiary care centres in 10 countries. The study enrolled women with a diagnosis of endometriosis and with at least one centre-specific contact related to endometriosis-associated symptoms in 2008. The main outcome measures were health care costs, costs of productivity loss, total costs and quality-adjusted life years. Predictors of costs were identified using regression analysis.

RESULTS

Data analysis of 909 women demonstrated that the average annual total cost per woman was €9579 (95% confidence interval €8559-€10 599). Costs of productivity loss of €6298 per woman were double the health care costs of €3113 per woman. Health care costs were mainly due to surgery (29%), monitoring tests (19%) and hospitalization (18%) and physician visits (16%). Endometriosis-associated symptoms generated 0.809 quality-adjusted life years per woman. Decreased quality of life was the most important predictor of direct health care and total costs. Costs were greater with increasing severity of endometriosis, presence of pelvic pain, presence of infertility and a higher number of years since diagnosis.

CONCLUSIONS

Our study invited women to report resource use based on endometriosis-associated symptoms only, rather than drawing on a control population of women without endometriosis. Our study showed that the economic burden associated with endometriosis treated in referral centres is high and is similar to other chronic diseases (diabetes, Crohn's disease, rheumatoid arthritis). It arises predominantly from productivity loss, and is predicted by decreased quality of life.

A polymorphism in a let-7 microRNA binding site of KRAS in women with endometriosis

Endometriosis is found in 5-15% of women of reproductive age and is more frequent in relatives of women with the disease. Activation of KRAS results in de novo endometriosis in mice, however, activating KRAS mutations have not been identified in women. We screened 150 women with endometriosis for a polymorphism in a let-7 microRNA (miRNA) binding site in the 3'-UTR of KRAS and detected a KRAS variant allele in 31% of women with endometriosis as opposed to 5% of a large diverse control population. KRAS mRNA and protein expression were increased in cultured endometrial stromal cells of women with the KRAS variant. Increased KRAS protein was due to altered miRNA binding as demonstrated in reporter assays. Endometrial stromal cells from women with the KRAS variant showed increased proliferation and invasion. In a murine model, endometrial xenografts containing the KRAS variant demonstrated increased proliferation and decreased progesterone receptor levels. These findings suggest that an inherited polymorphism of a let-7 miRNA binding site in KRAS leads to abnormal endometrial growth and endometriosis. The LCS6 polymorphism is the first described genetic marker of endometriosis risk.

Patients with endometriosis of the rectosigmoid have a higher percentage of natural killer cells in peripheral blood

STUDY OBJECTIVE

To estimate the concentration of natural killer (NK) cells in the peripheral blood in patients with and without endometriosis.

DESIGN

Case-control study (Canadian Task Force classification II-2).

SETTING

Tertiary referral hospital.

PATIENTS

One hundred fifty-five patients who had undergone videolaparoscopy were divided into 2 groups: those with endometriosis (n = 100) and those without endometriosis (n = 55).

INTERVENTIONS

The percentage of NK cells relative to peripheral lymphocytes was quantified at flow cytometry in 155 patients who had undergone laparoscopy. In addition to verifying the presence of endometriosis, stage of disease and the sites affected were also evaluated.

MEASUREMENTS AND MAIN RESULTS

The mean (SD) percentage of NK cells was higher (15.3% [9.8%]) in patients with endometriosis than in the group without the disease (10.6% [5.8%]) (p < .001). The percentage of NK cells was highest (19.8 [10.3%]) in patients with advanced stages of endometriosis and in those in whom the rectosigmoid colon was affected. In a statistical model of probability, the association of this marker (NK cells ≥11%) with the presence of symptoms such as pain and intestinal bleeding during menstruation and the absence of previous pregnancy yielded a 78% likelihood of the rectosigmoid colon being affected.

CONCLUSION

Compared with patients without endometriosis, those with endometriosis demonstrate a higher concentration of peripheral NK cells. The percentage of NK cells is greater, primarily in patients with advanced stages of endometriosis involving the rectosigmoid colon. Therefore, it may serve as a diagnostic marker for this type of severe endometriosis, in particular if considered in conjunction with the symptoms.

Failure to detect significant association between estrogen receptor-alpha gene polymorphisms and endometriosis in Japanese women

OBJECTIVES

The aim of the study was to test whether estrogen receptor 1 (ESR1) gene polymorphisms are correlated with the risk of the development of endometriosis in Japanese women, as a preliminary study.

METHODS

To compare allelic frequencies and genotype distributions, a case-control study of 100 affected women and 143 women with no evidence of disease was performed using 10 microsatellite repeat markers and 66 single-nucleotide polymorphisms (SNPs) in the ESR1 gene region.

RESULTS

Although our results might be insufficient to detect genetic susceptibility, owing to the small sample size and low genetic power, statistical analysis of the differences in allelic frequency between the cases and controls at each microsatellite locus demonstrated that no microsatellite locus in the ESR1 gene displayed a significant association with the disease when multiple testing was taken into account. Also, there were no statistically significant differences in the SNP allele frequencies and genotypes between the cases and controls when multiple testing was taken into account.

CONCLUSION

The findings in our pilot study suggest that ESR1 polymorphisms do not contribute to endometriosis susceptibility.

Mouse model of surgically-induced endometriosis by auto-transplantation of uterine tissue

Endometriosis is a chronic, painful disease whose etiology remains unknown. Furthermore, treatment of endometriosis can require laparoscopic removal of lesions, and/or chronic pharmaceutical management of pain and infertility symptoms. The cost associated with endometriosis has been estimated at 22 billion dollars per year in the United States. To further our understanding of mechanisms underlying this enigmatic disease, animal models have been employed. Primates spontaneously develop endometriosis and therefore primate models most closely resemble the disease in women. Rodent models, however, are more cost effective and readily available. The model that we describe here involves an autologous transfer of uterine tissue to the intestinal mesentery (Figure 1) and was first developed in the rat and later transferred to the mouse. The goal of the autologous rodent model of surgically-induced endometriosis is to mimic the disease in women. We and others have previously shown that the altered gene expression pattern observed in endometriotic lesions from mice or rats mirrors that observed in women with the disease. One advantage of performing the surgery in the mouse is that the abundance of transgenic mouse strains available can aid researchers in determining the role of specific components important in the establishment and growth of endometriosis. An alternative model in which excised human endometrial fragments are introduced to the peritoneum of immunocompromised mice is also widely used but is limited by the lack of a normal immune system which is thought to be important in endometriosis. Importantly, the mouse model of surgically induced endometriosis is a versatile model that has been used to study how the immune system, hormones and environmental factors affect endometriosis as well as the effects of endometriosis on fertility and pain.

HMGA gene rearrangement is a recurrent somatic alteration in polypoid endometriosis

The pathogenesis of endometriosis is unclear, and several genetic, endocrine, immune, and environmental agents have been evaluated with no putative causative factors identified. Here, we show somatic genetic alterations involving HMGA1 (6p21) and HMGA2 (12q15) in 3 cases of polypoid endometriosis. The lesions involved the small bowel mesentery and perirectal soft tissue in 1 case and the posterior vaginal fornix and sigmoid colon serosa in 2 other cases, respectively. All had a polypoid configuration with cystically dilated irregular glands and fibrotic stroma, containing thick-walled vessels. Conventional cytogenetic analysis of 1 case showed 46,XX,t(5;12)(q13;q15) in all metaphases. Fluorescence in situ hybridization studies confirmed the balanced rearrangement of HMGA2. HMGA1 rearrangements were present in 2 additional cases. Rearrangements were exclusively found in the stromal component but not in the glandular component. These findings suggest that HMGA rearrangements likely contribute to the pathogenesis of endometriosis. However, additional studies are needed to better define the biologic role of this genetic alteration.

A novel gene-environment interaction involved in endometriosis

OBJECTIVE

To establish a well-defined cohort for genetic epidemiology studies of endometriosis and conduct a pilot study to confirm validity using existing data associated with endometriosis.

METHODS

Between January and May 2010, a nested cohort within a population-based biobank was established in Marshfield, Wisconsin, USA. The inclusion criteria were women who had laparoscopy or hysterectomy. Fifty-one pleiotropic genetic polymorphisms and other established risk factors, such as smoking status and body mass index, were compared between endometriosis cases and controls.

RESULTS

From the existing biobank, 796 cases and 501 controls were identified, and 259 women with endometriosis were enrolled specifically for the nested cohort within this biobank. A single nucleotide polymorphism in the MMP1 gene significantly differed between cases and controls only when stratified by smoking status. Minor allele frequency was higher in control women who smoked than in women with endometriosis who smoked (55.5% versus 45.5%, χ(2)=8.2, P=0.017); the inverse relationship was found in non-smoker control women.

CONCLUSIONS

Women with endometriosis were successfully recruited to participate in a general biobank, and a novel gene-environment interaction was identified. The findings suggest that important potential genetic associations may be missed if gene-environment interactions with known epidemiologic risk factors are not considered.

Risk Factors for Endometriosis in a German Case-Control Study

Objective: The etiology of endometriosis is still a research field in which few consistent data are available. Large case-control studies or even cohort studies are rare, and most of the published data are conflicting. The aim of the present study was therefore to examine common epidemiological and endometriosis-specific risk factors in a German case-control study. Design: From 2001 to 2010, a pool of 595 laparoscopically confirmed cases and 475 controls were recruited in a hospital-based setting. After matching for age, 298 cases and 300 controls remained in the pool. Age at menarche, menstrual cycle length, duration of menstrual bleeding, number of pregnancies, live births, miscarriages, use of contraceptive pills, body mass index (BMI), and smoking status were analyzed with logistic regression models predicting endometriosis case-control status. Results: Menstrual cycle length, duration of menstrual bleeding, number of pregnancies, number of miscarriages, and smoking status, as relevant predictors for endometriosis case-control status, were identified as risk factors for endometriosis. Other factors such as age at menarche, number of live births, ever having used contraceptive pills, and BMI were not predictive. Conclusions: This hospital-based case-control study reproduced most of the familiar risk factors. Comparison of this study with others reveals a wide variety of effect sizes and directions of association with risk factors and may increase the information available about the characteristics of the patient population being treated in the relevant hospital setting.

Immunological aspects of endometriosis: an update

PROBLEM

Endometriosis is a very complex disease that profoundly affects the quality of life of many women.

METHOD OF STUDY

A review of the relationships between the female immune system and the occurrence and development of endometriosis.

RESULTS

Function and dysfunction of the female immune system plays important roles in the initiation and progression of the disease and its relation to infertility and cancer.

CONCLUSIONS

Owing to obvious associations between endometriosis and the immune system, future treatment strategies might be based on immunological concepts and methods.

Sex steroid hormones and reproductive disorders: impact on women's health

The role of sex steroid hormones in reproductive function in women is well established. However, in the last two decades it has been shown that receptors for estrogens, progesterone and androgens are expressed in non reproductive tissue /organs (bone, brain, cardiovascular system) playing a role in their function. Therefore, it is critical to evaluate the impact of sex steroid hormones in the pathophysiology of some diseases (osteoporosis, Alzheimer, atherosclerosis). In particular, women with primary ovarian insufficiency, polycystic ovary syndrome, endometriosis and climacteric syndrome may have more health problems and therefore an hormonal treatment may be crucial for these women.

Assessment of endometrial receptivity

OBJECTIVE

To provide a focused review of the scientific literature pertaining to endometrial receptivity.

DESIGN

Review of the literature and appraisal of relevant articles.

SETTING

Academic teaching hospital.

PATIENT(S)

Women with infertility.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

Critical review of the literature.

RESULT(S)

Although a consensus has been achieved regarding the existence of a temporally defined period during which embryo attachment and invasion can occur (called the "window of implantation"), reliable methods to assess "receptivity" have not been established or adequately validated. In women with certain gynecologic disorders, including endometriosis, tubal disease, and polycystic ovary syndrome, endometrial receptivity seems to be compromised, leading to infertility and pregnancy loss. The establishment of reliable biomarkers for the detection of defects in endometrial receptivity has been a long-sought goal that remains an elusive target. The validation of endometrial biomarkers will require properly designed and implemented studies based on the recognition that endometrial receptivity defects are not equally distributed in women with endometriosis or these other conditions.

CONCLUSION(S)

Rapidly advancing technologies are bringing new biomarkers to the clinical arena that promise to further reveal the complexities of the implantation process.

[Intestinal endometriosis]

Endometriosis affects 6 to 10 % of all women of childbearing age. Intestinal involvement is defined by muscularis infiltration and has been estimated to occur in 8 % to 12 % of women with endometriosis. The most common sites are rectum, sigmoid and ileocaecal junction. In most cases, intestinal endometriosis is associated with deep infiltrating endometriosis, multifocal and aggressive form of endometriosis, responsible for refractory pelvic pain and infertility. The symptoms are nonspecific but are characterized by cyclic exacerbation of pain. The preoperative work-up includes a rectal endoscopic ultrasonography, a transvaginal ultrasonography, a pelvic magnetic resonance imaging and a multidetector CT scan. There is currently no cure other than surgical removal of lesions. Medical treatments are based on a hormone used to block ovarian function.

Psychological factors in chronic pelvic pain in women: relevance and application of the fear-avoidance model of pain

Chronic pelvic pain in women is a debilitating, costly condition often treated by physical therapists. The etiology of this condition is multifactorial and poorly understood, given the complex interplay of muscles, bones, and soft tissue that comprise the pelvis. There are few guidelines directing treatment interventions for this condition. In the last decade, several investigators have highlighted the role of psychological variables in conditions such as vulvodynia and painful bladder syndrome. Pain-related fear is the focus of the fear-avoidance model (FAM) of pain, which theorizes that some people are more likely to develop and maintain pain after an injury because of their emotional and behavioral responses to pain. The FAM groups people into 2 classes on the basis of how they respond to pain: people who have low fear, confront pain, and recover from injury and people who catastrophize pain-a response that leads to avoidance/escape behaviors, disuse, and disability. Given the presence of pain-related cognitions in women with chronic pelvic pain, including hypervigilance, catastrophizing, and anxiety, research directed toward the application of the FAM to guide therapeutic interventions is warranted. Isolated segments of the FAM have been studied to theorize why traditional approaches (ie, medications and surgery) may not lead to successful outcomes. However, the explicit application of the FAM to guide physical therapy interventions for women with chronic pelvic pain is not routine. Integrating the FAM might direct physical therapists' clinical decision making on the basis of the pain-related cognitions and behaviors of patients. The aims of this article are to provide information about the FAM of musculoskeletal pain and to provide evidence for the relevance of the FAM to chronic pelvic pain in women.

Impact of endometriosis on quality of life and work productivity: a multicenter study across ten countries

OBJECTIVE

To assess the impact of endometriosis on health-related quality of life (HRQoL) and work productivity.

DESIGN

Multicenter cross-sectional study with prospective recruitment.

SETTING

Sixteen clinical centers in ten countries.

PATIENT(S)

A total of 1,418 premenopausal women, aged 18-45 years, without a previous surgical diagnosis of endometriosis, having laparoscopy to investigate symptoms or to be sterilized.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

Diagnostic delay, HRQoL, and work productivity.

RESULT(S)

There was a delay of 6.7 years, principally in primary care, between onset of symptoms and a surgical diagnosis of endometriosis, which was longer in centers where women received predominantly state-funded health care (8.3 vs. 5.5 years). Delay was positively associated with the number of pelvic symptoms (chronic pelvic pain, dysmenorrhoea, dyspareunia, and heavy periods) and a higher body mass index. Physical HRQoL was significantly reduced in affected women compared with those with similar symptoms and no endometriosis. Each affected woman lost on average 10.8 hours (SD 12.2) of work weekly, mainly owing to reduced effectiveness while working. Loss of work productivity translated into significant costs per woman/week, from US$4 in Nigeria to US$456 in Italy.

CONCLUSION(S)

Endometriosis impairs HRQoL and work productivity across countries and ethnicities, yet women continue to experience diagnostic delays in primary care. A higher index of suspicion is needed to expedite specialist assessment of symptomatic women. Future research should seek to clarify pain mechanisms in relation to endometriosis severity.

A feasibility study exploring the role of Chinese herbal medicine in the treatment of endometriosis

BACKGROUND

Endometriosis is a common and disabling gynecologic condition affecting between 5% and 15% of women of childbearing age. Conventional medical intervention has unpleasant side-effects, and symptoms frequently return after treatment. Preliminary evidence suggests Chinese herbal medicine (CHM) may contribute to the treatment of endometriosis.

OBJECTIVES

The aims of this study were to test the feasibility of a novel methodology for investigating individualized decoctions of CHM rigorously and to gather preliminary data on the treatment effect of CHM for a larger definitive trial.

DESIGN

This was a 16-week prospective, double blinded, randomized controlled trial of 40 women with laparoscopically confirmed endometriosis.

SETTINGS

The trial was conducted at a private CHM clinic in Hove (U.K.) and at a National Health Service outpatient clinic in London (U.K.).

INTERVENTIONS

Participants were initially randomized to either wait-list control (WLC) or treatment groups to receive either individualized CHM decoctions or a therapeutically inert placebo decoction.

OUTCOME MEASURES

Four 10-cm visual analogue scales (VAS) were used to measure menstrual pain, daily pain, and pain on intercourse and bowel movement; these measurements were recorded weekly. The Endometriosis Health Profile-30 (EHP-30) endometriosis-specific quality-of-life questionnaire was completed at the beginning and at the end of the trial. The Measure Yourself Medical Outcomes Profile (MYMOP) a patient-centered health questionnaire was completed monthly. Liver and renal function was measured at 0, 4, 8, and 16 weeks.

RESULTS

Twenty-eight (28) women completed the trial. High dropout rates led to the suspension of the WLC. Randomization, double blinding, and allocation concealment was achieved successfully. Adjusted mean differences favored the active treatment in the EHP-30 and MYMOP scores. VAS scores favored the active treatment for relief of menstrual pain and the placebo group for reduction of daily pain.

CONCLUSIONS

the methodology successfully allowed individualized CHM decoctions to be tested rigorously. There are nonspecific contextual effects from CHM that require further investigation. Provisional data were generated to warrant a larger, more-definitive study.

Circulating endothelial progenitor cells are up-regulated in a mouse model of endometriosis

Endometriosis is a debilitating disease characterized by the growth of ectopic endometrial tissue. It is widely accepted that angiogenesis plays an integral part in the establishment and growth of endometriotic lesions. Recent data from a variety of angiogenesis-dependent diseases suggest a critical role of bone marrow–derived endothelial progenitor cells (EPCs) in neovascularization. In this study we examined the blood levels of EPCs and mature circulating endothelial cells in a mouse model of surgically induced endometriosis. Fluorescence-activated cell sorting analysis revealed elevated levels of EPCs in the blood of mice with endometriosis compared with control subject that underwent a sham operation. EPC concentrations positively correlated with the amount of endometriotic tissue and peaked 1 to 4 days after induction of disease. In a green fluorescent protein bone marrow transplant experiment we found green fluorescent protein–positive endothelial cells incorporated into endometriotic lesions but not eutopic endometrium, as revealed by flow cytometry and immunohistochemistry. Finally, treatment of endometriosis-bearing mice with the angiogenesis inhibitor Lodamin, an oral nontoxic formulation of TNP-470, significantly decreased EPC levels while suppressing lesion growth. Taken together, our data indicate an important role for bone marrow–derived endothelial cells in the pathogenesis of endometriosis and support the potential clinical use of anti-angiogenic therapy as a novel treatment modality for this disease.

Non-health-care costs associated with endometriosis

BACKGROUND

This study aims to quantify the non-health-care costs of endometriosis in a sample of Belgian patients over a 30-month period.

METHODS

A longitudinal study enrolled patients who underwent surgical treatment for endometriosis in University Hospitals Leuven. Self-reported patient questionnaires measured costs at 1 month prior to surgical treatment and at 6, 12, 18 and 24 months following treatment. The number of days of work absence was valued using gross monthly income to estimate costs of productivity loss. Analysis included patient expenditure on support with household activities. The costs per patient over 6 months were obtained by linear extrapolation.

RESULTS

Of 394 eligible patients, 180 participated in the study (response rate of 46%). The highest productivity loss was incurred during the 6 months preceding surgical treatment (€1514 ± 2576) and the 6 months following treatment (€2496 ± 4144). Mean costs dropped to €115-€225 during the following 6-month periods. Similarly, costs of support with household activities peaked during the 6 months preceding surgical treatment (€982 ± 908) and during the subsequent 6 months (€981 ± 1085), after which they dropped to €500-€675 during the following 6-month periods. Patients with severe endometriosis (Stage IV) (€4943) had higher total non-health-care costs over the 30-month period than patients with minimal-to-moderate endometriosis (Stages I-III) (€4510) (P = 0.048).

CONCLUSIONS

As our study did not include a control population of women without endometriosis, patients were asked to report non-health-care costs associated with endometriosis only. Results show that the highest non-health-care costs associated with endometriosis are incurred during the 6 months prior to and following surgical treatment.

Ovarian cancer-associated polymorphisms in the BNC2 gene among women with endometriosis

BACKGROUND

Endometriosis is a common benign gynaecological disease. Epidemiological studies have demonstrated associations between endometriosis and ovarian cancer. Recent genome-wide association studies of ovarian cancer have identified several single nucleotide polymorphisms (SNPs) in the Basonuclin 2 (BNC2) gene. In this study, we investigated these polymorphism in women with endometriosis.

METHODS

Six SNPs in and upstream of the BNC2 gene (rs3814113, rs4445329, rs10962656, rs12379183, rs10756819 and rs1339552) were investigated using TaqMan allelic discrimination analysis in a Caucasian population (cases: 798, controls: 351). Allelic frequencies were used as main outcome measure.

RESULTS

No associations were observed between the analysed SNPs and endometriosis.

CONCLUSIONS

Our results suggest that the analysed polymorphisms in the BNC2 gene are unlikely to contribute to the previously reported risk of ovarian cancer in women with endometriosis.

Quantification of the impact of endometriosis symptoms on health-related quality of life and work productivity

OBJECTIVE

To quantify the impact of endometriosis-related symptoms on physical and mental health status, health-related quality of life, and work-related aspects (absenteeism, presenteeism, work productivity, and activity impairment).

DESIGN

Cross-sectional quantitative study.

SETTING

Academic and research institution.

PATIENT(S)

Women (n = 193) with self-reported surgically diagnosed endometriosis from the Endometriosis Patient Registry at Ponce School of Medicine and Health Sciences (PSMHS).

INTERVENTION(S)

Anonymous questionnaire divided into three sections consisting of questions from the Patient Health Survey (SF-12), the Endometriosis Health Profile (EHP-5), and the Work Productivity and Activity Impairment Survey (WPAI).

MAIN OUTCOME MEASURE(S)

Quantification of impact of endometriosis symptoms on physical and mental health status, health-related quality of life, absenteeism, presenteeism, work productivity, and activity impairment.

RESULT(S)

Patients had SF-12 scores denoting statistically significant disability in the physical and mental health components. They also reported an average of 7.41 hours (approximately one working day) of work time lost during the week when the symptoms are worse. In addition, the WPAI scores showed a high impact on work-related domains: 13% of average loss in work time (absenteeism), 65% of work impaired (presenteeism), 64% of loss in efficiency levels (work productivity loss), and 60% of daily activities perturbed (activity impairment).

CONCLUSION(S)

Endometriosis symptoms such as chronic, incapacitating pelvic pain and infertility negatively and substantially impact the physical and mental health status, health-related quality of life, and productivity at work of women.

Effectiveness of the association micronized N-Palmitoylethanolamine (PEA)-transpolydatin in the treatment of chronic pelvic pain related to endometriosis after laparoscopic assessment: a pilot study

OBJECTIVE

Aim of our study was to evaluate the effectiveness of the association between N-Palmitoylethanolamine and transpolydatin in the management of chronic pelvic pain related to EMS.

STUDY DESIGN

This was a randomized, double-blind, parallel-group, placebo-controlled clinical trial involving 61 subjects, submitted to a first line laparoscopic conservative surgery, who were randomized into 3 groups receiving: group A (n=21) the association N-Palmitoylethanolamine-transpolydatin 400 mg + 40 mg twice a day for 3 months; group B (n=20) the placebo for 3 months; group C (n=20) a single course of Celecoxib 200mg twice a day for 7 consecutive days. Assessments of the severity of pelvic endometriosis (pelvic pain, dysmenorrhoea and dyspareunia) were recorded before and after treatment on a questionnaire and a 10-point VAS. Differences between groups were verified with Kruskal-Wallis ANOVA for non-parametric multiple comparisons.

RESULTS

A marked decrease in dysmenorrhoea, dyspareunia and pelvic pain was observed in all groups, and the association between N-Palmitoylethanolamine and transpolydatin resulted to be more effective than placebo (P<.001). Additionally, the treatment with Celecoxib resulted in a decrease in pelvic pain more effective either than the association N-Palmitoylethanolamine and transpolydatin or placebo.

CONCLUSION

These preliminary results show that the association between micronized N-Palmitoylethanolamine and transpolydatin is effective in the management of pelvic pain related to endometriosis after laparoscopy. Additionally, this association seems to be safe, shows an optimal control of pain and can be used in patients who are unable to receive other therapies.

Activation of mutated K-ras in donor endometrial epithelium and stroma promotes lesion growth in an intact immunocompetent murine model of endometriosis

Endometriosis is a common chronic gynaecological condition, affecting 5-10% of women of child-bearing age. Its study has been hampered by lack of genetically tractable models. We transplanted steroid-manipulated, menstrual-like endometrium from K-ras(G12V/+) /Ah-Cre(+/+) /ROSA26R-LacZ(+/+) mice into gonad-intact immunocompetent wild-type mice. This led to endometriosis-like lesion development. Long-term lesion survival depended on the presence of the activated K-ras in the small proportion of the cells in the mature lesion that had undergone Cre-mediated K-ras activation. LacZ activity demonstrated Cre-mediated recombination in both endometrial epithelial cells and stromal cells, and transgenic K-ras expression was confirmed by RT-PCR. The endometriosis lesions developed without exogenous oestradiol supplementation and anti-oestrogen (fulvestrant, ICI 182780) treatment greatly suppressed their growth. Immunohistochemistry confirmed that as in human endometriosis, there was invasion and activation of fibroblasts, endothelial cells, and macrophages, with marked collagen deposition in the lesions. This model provides an opportunity to investigate endometriosis lesion establishment, growth, and regression in genetically tractable, immunocompetent, and hormonally intact mice. Furthermore, for the first time it provides a suitable model to test clinically validated driver genes in a faithful mouse model of the predisposing endometriotic lesion, thus providing the correct cellular context and microenvironment for ovarian clear cell carcinogenesis.

Inflammatory pathways in endometrial disorders

Complex interactions between the endocrine and immune systems govern the key endometrial events of implantation and menstruation. In contrast to other tissue sites, cyclical endometrial inflammation is physiological. However, dysregulation of this inflammatory response can lead to endometrial disorders. This review examines the inflammatory processes occurring in the normal endometrium during menstruation and implantation, highlighting recent advances in our understanding and gaps in current knowledge. Subsequently, the role of inflammatory pathways in the pathology of various common endometrial conditions is discussed, including heavy menstrual bleeding, dysmenorrhoea (painful periods), uterine fibroids, endometriosis and recurrent miscarriage.

Surgical procedures and their cost estimates among women with newly diagnosed endometriosis: a US database study

OBJECTIVE

This descriptive study assessed the rate and costs of surgical procedures among newly diagnosed endometriosis patients.

METHODS

Utilizing the Medstat MarketScan database, commercially insured women aged 18-45 with endometriosis newly diagnosed during 2006-2007 were identified. Each endometriosis patient was matched to four women without endometriosis (population controls) based on age and region of residence. Surgical procedures received during the 12 months post-diagnosis were assessed. Costs of surgical procedures were the amount paid by the insurance companies.

RESULTS

This study identified 15,891 women with newly diagnosed endometriosis and 63,564 population controls. More than 65% of endometriosis patients received an endometriosis-related surgical procedure within 1 year of the initial diagnosis. The most common procedure was therapeutic laparoscopy (31.6%), followed by abdominal hysterectomy (22.1%) and vaginal hysterectomy (6.8%). Prevalence and type of surgery performed varied by patient age, including a hysterectomy rate of approximately 16% in patients younger than 35 and 37% among patients aged 35-45 years. Average costs ranged from $4,289 (standard deviation [SD]: $3,313) for diagnostic laparoscopy to $11,397 (SD: $8,749) for abdominal hysterectomy.

LIMITATIONS

Diagnosis of endometriosis cannot be validated against medical records, and information on the severity of endometriosis-related symptoms is not available in administrative claims data.

CONCLUSIONS

Over 65% of patients had endometriosis-related surgical procedures, including hysterectomy, within 1 year of being diagnosed with endometriosis. The cost of surgical procedures related to endometriosis places a significant financial burden on the healthcare system.