Pathogenesis of deep endometriosis

Endometriosis-Associated Macrophages: Origin, Phenotype, and Function

Endometriosis is a complex, heterogeneous, chronic inflammatory condition impacting ~176 million women worldwide. It is associated with chronic pelvic pain, infertility, and fatigue, and has a substantial impact on health-related quality of life. Endometriosis is defined by the growth of endometrial-like tissue outside the uterus, typically on the lining of the pelvic cavity and ovaries (known as "lesions"). Macrophages are complex cells at the center of this enigmatic condition; they are critical for the growth, development, vascularization, and innervation of lesions as well as generation of pain symptoms. In health, tissue-resident macrophages are seeded during early embryonic life are vital for development and homeostasis of tissues. In the adult, under inflammatory challenge, monocytes are recruited from the blood and differentiate into macrophages in tissues where they fulfill functions, such as fighting infection and repairing wounds. The interplay between tissue-resident and recruited macrophages is now at the forefront of macrophage research due to their differential roles in inflammatory disorders. In some cancers, tumor-associated macrophages (TAMs) are comprised of tissue-resident macrophages and recruited inflammatory monocytes that differentiate into macrophages within the tumor. These macrophages of different origins play differential roles in disease progression. Herein, we review the complexities of macrophage dynamics in health and disease and explore the paradigm that under disease-modified conditions, macrophages that normally maintain homeostasis become modified such that they promote disease. We also interrogate the evidence to support the existence of multiple phenotypic populations and origins of macrophages in endometriosis and how this could be exploited for therapy.

Development of localized cul-de-sac endometrioid carcinoma associated with deep infiltrating endometriosis during remission of early endometrial cancer

•

A cul-de-sac endometrioid carcinoma adjacent to extraovarian endometriosis was identified during remission of endometrial cancer.

•

The origin of the cul-de-sac tumor was malignant transformation of deep infiltrating endometriosis.

•

Endometriosis-related cancer was identified in a woman with endometrial cancer during remission.

•

Hyperestrogenism due to infertility treatment may contribute to malignant transformation of deep infiltrating endometriosis.

Ovarian endometrioma - a possible finding in adolescent girls and young women: a mini-review

Young girls before menarche or menstruating adolescent women may experience long-term drug-resistant chronic pelvic pain, as well as other symptoms associated with pelvic mass. In such cases, it is of great importance to consider ovarian endometrioma in the differential diagnosis. In general, endometrioma is recognized as an ovarian cyst. However, in most cases, the pathology represents pseudocyst with a partial or complete endometrial-like lining with extraovarian adhesions and endometriotic implants which are likely to occur at the sites of ovarian adhesions and at the ceiling of the ovarian fossa. Ovarian endometriomas occur in 17–44% patients with endometriosis and account for 35% of all benign ovarian cysts. The time span from the onset of menarche to the time of endometrioma formation, which requires surgical intervention, has been evaluated to be a minimum of 4 years. The pathogenesis of early-life endometrioma may be different from other types of endometriosis. Diagnosis is often delayed, especially in adolescents, who tend to wait too long before seeking professional help. The three specific aims of treatment in adolescents with endometriosis and endometriomas are control of symptoms, prevention of further progression of the disease as well as preservation of fertility. Increasing evidence demonstrates association between ovarian endometriosis and ovarian cancer. In the present mini-review, we draw the particular attention of clinicians to such a possibility, even if relatively infrequently reported.

Predicting the likelihood of a live birth for women with endometriosis-related infertility

OBJECTIVE

Endometriosis affects 10% of women in reproductive age and alters fertility. Its management is still debated notably the timing of surgery and ART in infertility. Several tools have been created to guide the practitioner and the couple yet many limitations persist. The objective is to create a nomogram to predict the likelihood of a live birth after surgery followed by assisted reproductive technology (ART) for patients with endometriosis-related infertility.

STUDY DESIGN

All women in a public university hospital who attempted to conceive by ART after surgery for endometriosis-related infertility from 2004 to 2016 were included. We created a model using multivariable linear regression based on a retrospective database.

RESULT

Of the 297 women included, 171 (57.6%) obtained a live birth. Age, duration of infertility, number of ICSI-IVF cycles, ovarian reserve and the revised American Fertility Society (rAFS) score were included in the nomogram. The predictive model had an area under the curve (AUC) of 0.77 (95% CI, 0.75-0.79) and was well calibrated. The external validation of the model was achieved with an AUC of 0.71 (95% CI, 0.69-0.73) and calibration was good. The staging accuracy according to AUC criteria for the nomogram compared to the currently used Endometriosis Infertility Index to predict live births were 0.77 (95% CI, 0.75-0.79) and 0.60 (95% CI: 0.57-0.63), respectively.

CONCLUSION

This simple tool appears to accurately predict the likelihood of a live birth for a patient undergoing ART after surgery for endometriosis-related infertility. It could be used to counsel patients in their choice between spontaneous versus ART conception, or oocyte donation.

National trends in inpatient endometriosis admissions: Patients, procedures and outcomes, 2006-2015

INTRODUCTION

Despite guidance towards minimally invasive, outpatient procedures for endometriosis, many patients nonetheless receive inpatient care. Our objective was to assess trends in patient and hospital characteristics, surgical complications and hospital charges for women with an endometriosis-related inpatient admission in the United States.

METHODS

We conducted a pooled cross-sectional analysis of Healthcare Cost and Utilization Project Nationwide Inpatient Sample data. Visits were stratified into three time-period-defined cohorts (2006-2007, 2010-2011, and 2014 through the first three quarters of 2015). Visits were included if the patient was aged 18-49 years and the primary diagnosis code was for endometriosis (International Classification of Diseases, 9th Revision code 617.xx). We evaluated counts of inpatient admissions and rates of patient and hospital characteristics.

RESULTS

The number of inpatient admissions with a primary diagnosis code for endometriosis decreased by 72.8% from 2006 to 2015. At the same time, among those admitted for inpatient care for endometriosis, the proportions who had Medicaid insurance and multiple documented comorbidities increased. From 2006 to 2015, mean total hospital charges increased by 75% to $39,662 in 2015 US dollars, although average length of stay increased by <1 day.

CONCLUSIONS

The number of inpatient admissions with a primary diagnosis of endometriosis decreased over the past decade, while surgical complications and associated hospital charges increased. The share of patients with multiple comorbidities increased and an increasing proportion of inpatient endometriosis admissions were covered by Medicaid and occurred at urban teaching hospitals. These findings suggest a demographic shift in patients receiving inpatient care for endometriosis towards more complex, vulnerable patients.

Relationship between Patient Age and Disease Features in a Prospective Cohort of 1560 Women Affected by Endometriosis

OBJECTIVE

To assess the relationship between age, location of the disease, and surgical procedures performed in patients undergoing surgical management of endometriosis.

DESIGN

Retrospective study using data prospectively recorded in the North-West Inter Regional Female Cohort for Patients with Endometriosis database.

SETTING

University tertiary referral center.

PATIENTS

Women who underwent surgical management of symptomatic endometriosis between April 2009 and April 2014.

INTERVENTIONS

Patients were allocated to 6 groups according to their age at the time of surgery: ≤20, 21 to 25, 26 to 30, 31 to 35, 36 to 40 and >40 years. Patient characteristics, prior history, location of endometriotic lesions, stage of disease, intraoperative findings, and surgical procedures were retrieved from a prospectively recorded database.

MEASUREMENTS AND MAIN RESULTS

Patient characteristics, symptoms, location of endometriosis, and type of surgery performed were compared between groups. In total, 1560 procedures were performed. Of these, more than one-half were carried out in women between the age of 26 to 35 years and the majority were performed in women aged between 26 and 30 years. Only 2% of procedures were performed in women under the age of 20 years. The mean stage of the disease at the time of surgical diagnosis was stage II for women younger than 20 years, stage III for those in the age group of 21 to 25 years, and stage IV for those older than 26 years. The rate of diagnosis of deep colorectal nodules increased progressively from 20 to 26 years and remained stable thereafter.

CONCLUSION

Our data confirm that endometriosis is a disease that probably progresses from adolescence until the adult period when symptoms (pain or infertility) become debilitating and require surgery. Our data suggest that policies relating to the prevention and early diagnosis of endometriosis should focus on women younger than 25 years.

Safety of the laparoscopic management of patients with deep infiltrative endometriosis in a reference center in Pereira, Colombia. Retrospective cohorte, 2007-2016

Objective

Describe the intraoperative findings, procedures and the safety of laparoscopic surgical management of Deep Infiltration Endometriosis (DIE).

Materials and methods

A descriptive historical cohort study of patients with suspected pre-surgical diagnosis of DIE due to clinical findings, pelvic ultrasound or magnetic resonance imaging and histological confirmation of the disease. The patients were taken to minimally invasive surgery between 2007 and 2016 in a reference health institution located in Pereira, Colombia. Sociodemographic, clinical, intraoperative findings, types of procedure performed, intra and postoperative complications and post-surgical pain levels at 6 weeks were evaluated. A descriptive analysis was performed.

Results

One hundred and sixty seven patients were included. The most frequent location of the disease was the recto-vaginal septum (85.7 %). A total of 83 patients (49.7 %) had bowel endometriosis. Of these, 86 % had a shaving and 13.2 % segmental bowel resection. Four patients (2.4 %) had intraoperative complications. One was converted to laparotomy and other five (2.9 %) had post-surgical infection.

Conclusions

Laparoscopic management of DIE is an option to be considered with a 5% of complication frequency. Randomized studies with a control group are required for a better evaluation of safety and efficacy.

Endometriotic lesions

Endometriosis is a complex gynaecological condition affecting women of reproductive age. It is characterised by the presence of lesions containing endometrial glands and stroma outside the uterus. The disease is typically associated with pelvic pain (including dysmenorrhoea and dyspareunia), infertility and bowel-related symptoms. Endometriotic lesions have a highly variable presentation and most commonly occur in the abdominal cavity. These lesions are broadly classified into peritoneal, ovarian and deep infiltrating endometriosis. There have been observations of increased density of nerve fibres and neurological molecules in the endometriotic lesions compared to the uninvolved peritoneum of women without endometriosis and the presence of unmyelinated nerve fibres were higher near the glands. The lesion sites are characterised by a range of immunological alterations, and specific immune cell populations have also been known to synthesise and secrete neurogenic factors. Endometriotic lesions are capable of producing prostaglandins which are direct generators of pain and are capable of inducing inflammation. Diagnosing the disease involves direct visualisation of the lesions through a laparoscopic or laparotomy, which is followed by histopathological examination of biopsied or excised lesions. The staging of endometriosis due to its complexity is highly variable as presentation and gaps in knowledge pose a great challenge in the classification of the disease. The medical management of endometriosis aims at providing adequate analgesia and suppression of the activity of the lesion. A better understanding of endometriotic lesion relationships between innervations and specific clinical characteristics may elucidate aspects of pain mechanisms and infertility in endometriosis and facilitate the development of novel therapeutic approaches.

Influence of early-life factors on the development of endometriosis

Objective: Our aim was to study the association between early-life factors and the development of endometriosis. Methods: This case-control study included 440 women with surgically confirmed endometriosis (cases) and 880 women without endometriosis (controls). Information on early-life factors was ascertained retrospectively by in-person interviews with participants and their mothers. Adjusted odds ratios (ORs) and 95% confidence intervals (CIs) for the associations between endometriosis and maternal and paternal characteristics and foetal and infant exposures were estimated using unconditional logistic regression, adjusting for frequency matching and confounding variables. Results: We observed that women who were not breastfed as infants had twice the risk of endometriosis compared with women who were breastfed (adjusted OR 2.0; 95% CI 1.6, 4.5). Our data suggested an increased endometriosis risk with neonatal vaginal bleeding (adjusted OR 1.9; 95% CI 1.2, 4.3) and paternal smoking (adjusted OR 1.8; 95% CI 1.1, 4.9). Although the CIs included the null hypothesis value, caesarean section (adjusted OR 1.7; 95% CI 1.0, 3.5) and prematurity (adjusted OR 1.4; 95% CI 0.8, 3.7) were probably associated with the incidence of endometriosis. Conclusions: Some early-life factors including breastfeeding, neonatal vaginal bleeding and paternal smoking were associated with subsequent, surgically confirmed endometriosis in this cohort of Chinese women.

Endometriosis: advances and controversies in classification, pathogenesis, diagnosis, and treatment

Endometriosis is an enigmatic disease that could start at birth. Its pathogenesis is supported by different theories. Accumulating facts relate it to a multigenic disorder. In this review of recent publications, the principal symptoms of the disease, pain and infertility, as well as its pathogenesis, diagnosis, and classification will be addressed. Endometriosis presents three main variants: superficial peritoneal disease, deep infiltrating endometriosis, and ovarian endometriomas. The management of the disease, surgery, and medical and alternative therapies will be discussed. Special reference will be made to the quality of surgery and how to understand patients with endometriosis and endometriosis.

Biological differences between intrinsic and extrinsic adenomyosis with coexisting deep infiltrating endometriosis

RESEARCH QUESTION

Is there a biological difference between intrinsic and extrinsic adenomyosis with coexisting deep infiltrating endometriosis (DIE)?

DESIGN

In this prospective controlled study, biopsy specimens were collected after surgery from 23 women with intrinsic adenomyosis and 10 women with extrinsic adenomyosis with coexisting DIE lesions. Histological evaluation was carried out by immunoreaction to Ber-EP4 (epithelial cell marker) and CD10 (stromal cell marker). Tissue expression of oestrogen and progesterone receptors was analysed by immunohistochemistry. Tissue fibrosis was examined by Masson's trichrome staining with computer-based image analysis of fibrosis in respective samples.

RESULTS

The detection rate of coexistent DIE was significantly higher in women with extrinsic adenomyosis (9/10 [90.0%]) than in women with intrinsic adenomyosis (3/23 [13.0%]; P < 0.001). The pattern of Ber-EP4-stained glands and CD10-stained stromal cells of extrinsic adenomyosis was similar to that of coexistent DIE lesions. In contrast, the pattern of gland and stromal cells was similar to the endometrium in the cases with intrinsic adenomyosis. Unlike extrinsic adenomyosis, progesterone receptor expression was significantly decreased in both gland cells (P < 0.05) and stromal cells (P < 0.05) of intrinsic adenomyosis. Although relatively more fibrosis was seen in biopsy samples of extrinsic adenomyosis and coexistent DIE than in intrinsic adenomyosis and their coexistent DIE, no significant difference was found.

CONCLUSIONS

Extrinsic adenomyosis may be considered as adenomyosis externa based on a close histological and biological relationship between extrinsic adenomyosis and coexistent DIE. Our findings may contribute to the understanding of a possible biological origin of two newly classified intrinsic and extrinsic adenomyosis.

Neuropeptides Substance P and Calcitonin Gene Related Peptide Accelerate the Development and Fibrogenesis of Endometriosis

Endometriotic lesions are known to be hyperinnervated, especially in lesions of deep endometriosis (DE), which are frequently in close proximity to various nerve plexuses. DE lesions typically have higher fibromuscular content than that of ovarian endometriomas (OE) lesions, but the underlying reason remains elusive. Aside from their traditional role of pain transduction, however, whether or not sensory nerves play any role in the development of endometriosis is unclear. Here, we show that, thorough their respective receptors neurokinin receptor 1 (NK1R), calcitonin receptor like receptor (CRLR), and receptor activity modifying protein 1 (RAMP-1), neuropeptides substance P (SP) and calcitonin gene related peptide (CGRP) induce epithelial-mesenchymal transition (EMT), fibroblast-to-myofibroblast transdifferentiation (FMT) and further turn stromal cells into smooth muscle cells (SMCs) in endometriotic lesions, resulting ultimately in fibrosis. We show that SP and CGRP, or the rat dorsal root ganglia (DRG) supernatant, through the induction of NK1R and CGRP/CRLR/RAMP-1 signaling pathways, promoted EMT, FMT and SMM in endometriosis, resulting in increased migratory and invasive propensity, cell contractility, production of collagen, and eventually to fibrosis. Neutralization of NK1R and/or CGRP/CRLR/RAMP-1 abrogated these processes. Extended exposure of endometriotic stromal cells to SP and/or CGRP or the DRG supernatant induced increased expression of α-SMA, desmin, oxytocin receptor, and smooth muscle myosin heavy-chain. Finally, we show that DE lesions had significantly higher nerve fiber density, increased staining levels of α-SMA, NK1R, CRLR, and RAMP-1, concomitant with higher lesional fibrotic content than that of OE lesions. The extent of lesional fibrosis correlated positively with the staining levels of NK1R, CRLR, and RAMP-1, as well as the nerve fiber density in lesions. Thus, this study provides another piece of evidence that sensory nerves play an important role in promoting the development and fibrogenesis of endometriosis. It explains as why DE frequently have higher fibromuscular content than that of OE, highlights the importance of lesional microenvironment in shaping the lesional fate, gives more credence to the idea that ectopic endometrium is fundamentally wounds that go through repeated tissue injury and repair, and should shed much needed light into the pathophysiology of endometriosis.

Symptomatic endometriosis developing several years after menopause in the absence of increased circulating estrogen concentrations: a systematic review and seven case reports

Background

To review women with symptomatic and clinically progressive endometriosis after menopause in the absence of estrogen intake or excessive systemic endogenous production.

Design

Seven case reports and a systematic review of the literature from 1995 till February 2018.

Results

Only 7 case reports from the authors and 29 cases from the literature described women with either cystic ovarian or deep endometriosis. Severity, symptoms, and localization are highly variable. No case report describes symptomatic superficial typical lesions. In 22 of 36 women (61%), symptoms started more than 10 years after menopause.

Conclusions

Symptomatic and clinically progressive endometriosis after menopause in the absence of increased systemic estrogen concentrations or exogenous estrogen intake starts more than 10 years after menopause in the majority of women. This observation suggests that a genetic and/or epigenetic incident caused estrogen-independent progression, increased sensitivity to estrogens or increased local production of estrogens. This observation is important for understanding the pathophysiology of endometriosis, for the management of postmenopausal endometriosis, and for individualization of medical therapy of endometriosis since estrogen-independent endometriosis growth probably also occurs before menopause.

Human epidemiological evidence about the associations between exposure to organochlorine chemicals and endometriosis: Systematic review and meta-analysis

BACKGROUND

Endometriosis is a gynaecological disease characterized by the presence of ectopic endometrial tissue that affects women during their reproductive years, having a strong impact on their lives, fertility and healthcare costs. The aetiology remains largely unknown, but current evidence suggests that it is multi-causal and oestrogen-dependent. Many epidemiologic studies have explored associations between organochlorine chemicals (OCCs) and endometriosis, but the findings are inconsistent.

OBJECTIVES

A systematic review (SR) and meta-analysis were conducted to gather and synthesize all the available evidence from human epidemiological studies about the associations between OCCs and endometriosis.

DATA SOURCES

The searches were conducted in PubMed and Web of Science in June 2016 with a final follow-up in August 2018.

STUDY ELIGIBILITY CRITERIA

Only human epidemiological studies were considered, independent of participant age, body mass index or life-stage. Studies reporting individual measures of exposure to OCCs were included, considering but not limited to polychlorinated dibenzodioxins and dibenzofurans (PCDD/Fs), polychlorinated biphenyls (PCBs), or organochlorine pesticides (OCPs). The primary health outcome was presence of endometriosis, including all sub-types. Eligibility criteria excluded articles not written in English, conference papers, reviews and studies with overlapping information.

STUDY APPRAISAL AND SYNTHESIS METHODS

A SR protocol pre-registered at PROSPERO was applied in duplicate to gather and extract all eligible original papers from PUBMED and Web of Science databases. Odds ratios were pooled using the inverse variance method for random effects meta-analysis for each group of OCCs. Risk of bias was assessed using the National Toxicology Program/Office of Health Assessment and Translation (NTP/OHAT) Risk of Bias Rating Tool for Human and Animal Studies adapted to the review question. The confidence in the body of evidence and related level of evidence was measured by using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) based NTP/OHAT framework. The results were structured and presented in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines.

RESULTS

Of the 51 studies retained for the full-text screening, 17 provided effect sizes and metrics sufficient for pooling estimates through meta-analysis. The overall odds ratios and 95% confidence intervals were 1.65 (1.14; 2.39) for dioxins (n = 10), 1.70 (1.20; 2.39) for PCBs (n = 9), and 1.23 (1.13; 1.36) for OCPs (n = 5). Despite being statistically significant, these estimates should be considered with caution given the notable heterogeneity and small estimated effect size. Misclassification of exposure, due to varying laboratory detection rate capabilities, and disease status, due to varying definitions of endometriosis, were identified as major sources of uncertainty.

LIMITATIONS, CONCLUSIONS, AND IMPLICATIONS OF KEY FINDINGS

The level of evidence was considered to be "moderate" with "serious" risk of bias according the NTP/OHAT criteria, supporting the need for further well-designed epidemiological research to fill lingering data gaps. Given the complexity of endometriosis and lack of known biomarkers suitable for population-based research, carefully designed observational studies play an important role in better understanding the aetiology of endometriosis, as will evolving mixture modeling approaches capable of handling various environmental chemical exposures. Attention to critical windows of exposure will shed further light on the possible developmental origin of endometriosis. Considering the high economic and societal cost associated with endometriosis, further research on this field is urged.

SYSTEMATIC REVIEW REGISTRATION NUMBER

CRD42018080956.

Pathogenesis of endometriosis: the genetic/epigenetic theory

OBJECTIVE

To study the pathophysiology of endometriosis.

DESIGN

Overview of observations on endometriosis.

SETTING

Not applicable.

PATIENT(S)

None.

INTERVENTIONS(S)

None.

MAIN OUTCOME MEASURE(S)

The hypothesis is compatible with all observations.

RESULT(S)

Endometriosis, endometrium-like tissue outside the uterus, has a variable macroscopic appearance and a poorly understood natural history. It is a hereditary and heterogeneous disease with many biochemical changes in the lesions, which are clonal in origin. It is associated with pain, infertility, adenomyosis, and changes in the junctional zone, placentation, immunology, plasma, peritoneal fluid, and chronic inflammation of the peritoneal cavity. The Sampson hypothesis of implanted endometrial cells following retrograde menstruation, angiogenic spread, lymphogenic spread, or the metaplasia theory cannot explain all observations if metaplasia is defined as cells with reversible changes and an abnormal behavior/morphology due to the abnormal environment. We propose a polygenetic/polyepigenetic mechanism. The set of genetic and epigenetic incidents transmitted at birth could explain the hereditary aspects, the predisposition, and the endometriosis-associated changes in the endometrium, immunology, and placentation. To develop typical, cystic ovarian or deep endometriosis lesions, a variable series of additional transmissible genetic and epigenetic incidents are required to occur in a cell which may vary from endometrial to stem cells. Subtle lesions are viewed as endometrium in a different environment until additional incidents occur. Typical cystic ovarian or deep endometriosis lesions are heterogeneous and represent three different diseases.

CONCLUSION(S)

The genetic epigenetic theory is compatible with all observations on endometriosis. Implications for treatment and prevention are discussed.

Mesenteric vascular and nerve sparing surgery in laparoscopic segmental intestinal resection for deep infiltrating endometriosis

OBJECTIVE(S)

To investigate Mesenteric vascular and nerve Sparing Surgery (MSS) as surgical laparoscopic technique to perform segmental intestinal resection for deep infiltrating endometriosis (DIE).

STUDY DESIGN

Prospective cohort study between January 2013 and December 2016. Consecutive patients with suspected intestinal DIE underwent clinical and imaging evaluation to confirm intestinal involvement. Indications for radical surgery and surgical technique (intestinal resection versus shaving) were consistent with Abrão algorithm. Surgeons aimed to perform MSS in all the consecutive patients that required intestinal resection. MSS consists in mesenteric artery, branching arteries, and surrounding nerve fibers preservation by dissecting mesentery adherent to the intestinal wall. Data about history, preoperative and post-operative evaluation, surgery and complications were recorded. Symptoms were evaluated before and 30-60 days after surgery with numeric rating scale for pain. Constipation was evaluated with the Constipation Assessment Scale (CAS). Patients with diagnosis of irritable bowel syndrome, inflammatory bowel diseases, diverticulitis, and previous segmental intestinal resection were excluded.

RESULTS

Sixty-two out of 75 (82.7%) consecutive women with intestinal endometriosis underwent laparoscopic segmental intestinal resection performed with MSS. Major complications that required repeated operation occurred in 4 cases (6.5%). Anastomotic leakage occurred in only 1 case (1.6%). Dysmenorrhea (p < .001; r = -0.86), dyspareunia (p < .001; r = -0.80), dyschezia (p < .001; r = -0.86) and dysuria (p < .001; r = -0.56) were significantly improved after surgery. After an average of 33.1 months from surgery, severe constipation was reported only by two patients (3.6%) (CAS: 13-16). The median time from surgery to intestinal function recovery (flatus or stool passage) was one day. Logistic regression analysis showed constipation related to the distance from anal verge and time since surgery.

CONCLUSION(S)

MSS in laparoscopic intestinal resection for DIE may be reproducible, safe and effective. MSS could be combined with pelvic nerve-sparing surgery as an effective approach to improve intestinal symptoms after radical surgery for DIE that requires segmental intestinal resection.

Assessment of biomarkers in women with endometriosis-associated pain using the ENG contraceptive implant or the 52 mg LNG-IUS: a non-inferiority randomised clinical trial

OBJECTIVE

The aim of the study was to assess the serum levels of the following biomarkers in women with endometriosis-associated pelvic pain before and after six months of using the etonogestrel (ENG) contraceptive implant or the 52 mg levonorgestrel-releasing intrauterine system (LNG-IUS): cancer antigen (CA)-125, cluster of differentiation (CD) 23 and endometrial nerve fibre density.

METHODS

The study was conducted at the Department of Obstetrics and Gynaecology, University of Campinas Medical School, Brazil. A total of 103 women with endometriosis-associated pain diagnosed by surgery, transvaginal ultrasound and/or magnetic resonance imaging were included. Endometrial nerve fibre density and serum levels of CA-125 and soluble CD23 were assessed before and after six months of using the allocated method and were correlated to 10 cm visual analogue scale (VAS) scores for non-cyclical pelvic pain and dysmenorrhoea.

RESULTS

Both contraceptive methods significantly reduced concentrations of serum soluble CD23 and endometrial nerve fibre density (p < .001); however, CA-125 was significantly reduced only among users of the ENG implant (p < .05). No correlation was observed between reduction of biomarkers and improvement of VAS pain and dysmenorrhoea scores. No differences were observed between the ENG implant and the LNG-IUS.

CONCLUSION

Both progestin-only contraceptives significantly reduced two out of the three biomarkers evaluated. These two biomarkers could, therefore, be used as surrogate markers to follow up medical treatment of endometriosis-associated pain.

Vitamin D and Endometrium: A Systematic Review of a Neglected Area of Research

Growing evidence supports a role of vitamin D (VD) in reproductive health. Vitamin D receptor (VDR) is expressed in the ovary, endometrium, and myometrium. The biological actions of VD in fertility and reproductive tissues have been investigated but mainly using animal models. Conversely, the molecular data addressing the mechanisms underlying VD action in the physiologic endometrium and in endometrial pathologies are still scant. Levels of VDR expression according to the menstrual cycle are yet to be definitively clarified, possibly being lower in the proliferative compared to the secretory phase and in mid-secretory compared to early secretory phase. Endometrial tissue also expresses the enzymes involved in the metabolism of VD. The potential anti-proliferative and anti-inflammatory effects of VD for the treatment of endometriosis have been investigated in recent years. Treatment of ectopic endometrial cells with 1,25(OH)₂D₃ could significantly reduce cytokine-mediated inflammatory responses. An alteration of VD metabolism in terms of increased 24-hydroxylase mRNA and protein expression has been demonstrated in endometrial cancer, albeit not consistently. The effect of the active form of the vitamin as an anti-proliferative, pro-apoptotic, anti-inflammatory, and differentiation-inducing agent has been demonstrated in various endometrial cancer cell lines.

Effect of neuromuscular electrical stimulation for endometriosis-associated pain: A retrospective study

This retrospective study evaluated the effect of neuromuscular electrical stimulation (NMES) for the treatment of endometriosis-associated pain (EAP).A total of 154 patients with EAP were included and were divided into 2 groups in this retrospective study. Eighty-three patients were assigned a treatment group, and underwent NMES therapy, while 71 subjects in the control group were at waiting list. The primary outcome of pain was measured by the numerical rating scale (NRS) and the Endometriosis Symptom Severity scale (ESSS). The secondary outcome was quality of life, measured by the 36-Item Short Form Health Survey (SF-36). All outcomes were measured before and after 5-week and 10-week treatment. Moreover, we also recorded the adverse events in this study.After 5-week treatment, no significant differences in all outcome measurements were found between the 2 groups. However, after 10-week treatment, NMES therapy exerted better outcomes in NRS (P = .02), ESSS (P = .04), and SF-36 [Physical Component Summary (PCS), P < .01; Mental Component Summary (MCS), P < .01], compared with the patients at the waiting list. Moreover, no significant differences of all adverse events were found between the 2 groups, although mild and acceptable adverse events occurred in the treatment group.This study demonstrated that NMES is effective for treating patients with EAP.

Independent development of endometrial epithelium and stroma within the same endometriosis

The pathogenesis of endometriosis, a common benign but debilitating disease in women, remains elusive. The currently held stem cell theory posits that circulating progenitor/stem cells are deposited outside the uterus, where they differentiate into endometrial stroma and glandular tissue to establish endometriosis. Fundamental to testing this hypothesis is to elucidate the evolution of both tissue types. Here, we applied droplet digital PCR to analyze synonymous and missense somatic passenger mutations, which are neutral with respect to clonal selection, among six non-superficial endometriotic lesions. We found that among 19 mutations sequenced, all were significantly enriched in epithelial but not in stromal components of every lesion examined. Our data indicate that the evolution of non-superficial endometriosis is complex, in that epithelium is clonal and its development is independent of stroma, providing new insight into the genesis of endometriosis. Copyright © 2018 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

Colorectal Anastomotic Stenosis: Lessons Learned after 1643 Colorectal Resections for Deep Infiltrating Endometriosis

STUDY OBJECTIVE

To evaluate the incidence, risk factors, and treatment of colorectal anastomotic stenosis in patients who undergo rectosigmoid resection for deep infiltrating endometriosis (DIE).

DESIGN

Retrospective analysis of a prospective database (Canadian Task Force classification III).

SETTING

Public medical center.

PATIENTS

All women who underwent laparoscopic rectosigmoid resections for DIE at our hospital between January 2002 and December 2016.

INTERVENTION

All patients were evaluated clinically and endoscopically at 1 month and 3 months after bowel resection. Stenosis was defined as a lack of passage through the anastomosis of a 12-mm proctoscope. Symptomatic stenosis was defined as the presence of endoscopically confirmed stricture accompanied by at least 2 of the following symptoms: constipation, need to push, tenesmus, and ribbon stools. Only patients with symptomatic stenosis were studied. Demographic data, surgical techniques, and postoperative complications were recorded prospectively. Treatments and outcomes of anastomotic symptomatic strictures were analyzed.

MEASUREMENTS AND MAIN RESULTS

A total of 1643 patients underwent laparoscopic rectosigmoid resection at our hospital between January 2002 and December 2016. Among these, 104 patients (6.3%) presented with symptomatic anastomotic stenosis. The median patient age was 27 years (range, 23-44 years), and the median interval between diagnosis and the onset of symptomatic stenosis was 57 days (range, 21-64 days). The only statistically significant predictors of anastomotic stenosis were the presence of ileostomy (p = .01) and previous pelvic surgery (p = .002). Treatment of choice was always conservative. Of the 104 patients in the study cohort, 90 (86.5%) underwent 3 endoscopic dilatations. No patient required reoperation.

CONCLUSION

The anastomotic stricture is a recognized complication in patients following intestinal resection for DIE, and protective ileostomy is the sole modifiable factor related to anastomotic stenosis. Endoscopic dilatation is a valid option to treat this complication.

Endometriosis Malignant Transformation: Epigenetics as a Probable Mechanism in Ovarian Tumorigenesis

Endometriosis, defined as the presence of ectopic endometrial glands and stroma outside the uterine cavity, is a chronic, hormone-dependent gynecologic disease affecting millions of women across the world, with symptoms including chronic pelvic pain, dysmenorrhea, dyspareunia, dysuria, and subfertility. In addition, there is well-established evidence that, although endometriosis is considered benign, it is associated with an increased risk of malignant transformation, with the involvement of various mechanisms of development. More and more evidence reveals an important contribution of epigenetic modification not only in endometriosis but also in mechanisms of endometriosis malignant transformation, including DNA methylation and demethylation, histone modifications, and miRNA aberrant expressions. In this present review, we mainly summarize the research progress about the current knowledge regarding the epigenetic modifications of the relations between endometriosis malignant transformation and ovarian cancer in an effort to identify some risk factors probably associated with ectopic endometrium transformation.