Pathogenetic Mechanisms of Deep Infiltrating Endometriosis

Endometriosis-associated Ovarian Cancers

Endometriosis-associated cancers include clear cell and endometrioid ovarian carcinoma. A history of endometriosis has long been considered to be a risk factor for later development of these malignancies; however, recent molecular genetic evidence has provided unequivocal evidence that these lesions are in fact the precursors for endometriosis-associated cancers. Herein, we will explore the relationship between endometriosis and ovarian carcinomas, similarities between the premalignant lesions and their cancerous counterparts, and the potential role of mutations and the ovarian microenvironment that may contribute to malignant transformation.

Bowel endometriosis: diagnosis and management

The most common location of extragenital endometriosis is the bowel. Medical treatment may not provide long-term improvement in patients who are symptomatic, and consequently most of these patients may require surgical intervention. Over the past century, surgeons have continued to debate the optimal surgical approach to treating bowel endometriosis, weighing the risks against the benefits. In this expert review we will describe how the recommended surgical approach depends largely on the location of disease, in addition to size and depth of the lesion. For lesions approximately 5-8 cm from the anal verge, we encourage conservative surgical management over resection to decrease the risk of short- and long-term complications.

Molecular and Cellular Pathogenesis of Endometriosis

BACKGROUND

A substantial body of studies supports the view that molecular and cellular features of endometriotic lesions differ from those of eutopic endometrium. Apart from that, evidence exists that the eutopic endometrium from pa-tients with endometriosis differs from that of females without endometriosis.

OBJECTIVE

Aberrant expression profiles include a number of non-steroid signaling pathways that exert their putative influ-ence on the pathogenesis of endometriosis at least in part via crosstalk(s) with estrogen-mediated mechanisms. A rational to focus research on non-steroid signal pathways is that they might be remunerative targets for the development and selection of novel therapeutics to treat endometriosis possibly without affecting estrogen levels.

RESULTS AND CONCLUSION

In this article, we describe molecular and cellular features of endometriotic lesions and focus on the canonical WNT/β-signaling pathway, a key regulatory system in biology (including stem cell homeostasis) and often in pathophysiological conditions such as endometriosis. Recently emerged novel biological concepts in signal transduction and gene regulation like exosomes and microRNAs are discussed in their putative role in the pathogenesis of endometriosis.

Current understanding on pharmacokinetics, clinical efficacy and safety of progestins for treating pain associated to endometriosis

INTRODUCTION

Endometriosis is a chronic estrogen and progestogen responsive inflammatory disease associated with pain symptoms and infertility. The medical therapy of endometriosis aims to induce decidualization within the hormonally dependent ectopic endometrium, and it is often administered to ameliorate women' pain symptoms or to prevent post-surgical disease recurrence. A variety of progestins have been used in monotherapy for the medical management of women with endometriosis. Areas covered: This review aims to offer the reader a complete overview of pharmacokinetic (PK) and clinical efficacy of progestins for the treatment of endometriosis. Expert opinion: Each progestin has a distinct PK parameters and pharmacodynamics affinity not only for progesterone receptor, but also for other steroid receptors, such as estrogen, androgen, and glucocorticoid. Moreover, progestins can also be delivered in different formulations. All these characteristics influence their final biological effect. Randomized, controlled, non-blinded studies support the use of oral progestin-only treatment for pelvic pain associated with endometriosis. Currently, the only two progestins approved by Food and Drug Administration (FDA) for the treatment of endometriosis are norethindrone acetate (NETA) and depot medroxyprogesterone acetate (DMPA).

[Definition, description, clinicopathological features, pathogenesis and natural history of endometriosis: CNGOF-HAS Endometriosis Guidelines]

Endometriosis and adenomyosis are histologically defined. The frequency of endometriosis cannot be precisely estimated in the general population. Endometriosis is considered a disease when it causes pain and/or infertility. Endometriosis is a heterogeneous disease with three well-recognized subtypes that are often associated with each other: superficial endometriosis (SUP), ovarian endometrioma (OMA), and deep infiltrating endometriosis (DIE). DIE is frequently multifocal and mainly affects the following structures: the uterosacral ligaments, the posterior vaginal cul-de-sac, the bladder, the ureters, and the digestive tract (rectum, recto-sigmoid junction, appendix). The role of menstrual reflux in the pathophysiology of endometriosis is major and explains the asymmetric distribution of lesions, which predominate in the posterior compartment of the pelvis and on the left (NP3). All factors favoring menstrual reflux increase the risk of endometriosis (early menarche, short cycles, AUB, etc.). Inflammation and biosteroid hormones synthesis are the main mechanisms favoring the implantation and the growth of the lesions. Pain associated with endometriosis can be explained by nociception, hyperalgia, and central sensitization, associated to varying degrees in a single patient. Typology of pain (dysmenorrhea, deep dyspareunia, digestive or urinary symptoms) is correlated with the location of the lesions. Infertility associated with endometriosis can be explained by several non-exclusive mechanisms: a pelvic factor (inflammation), disrupting natural fertilization; an ovarian factor, related to oocyte quality and/or quantity; a uterine factor disrupting implantation. The pelvic factor can be fixed by surgical excision of the lesions that improves the chance of natural conception (NP2). The uterine factor can be corrected by an ovulation-blocking treatment that improves the chances of getting pregnant by in vitro fertilization (NP2). The impact of endometrioma exeresis on the ovarian reserve (NP2) should be considered when a surgery is scheduled. Endometriosis is a multifactorial disease, resulting from combined action of genetic and environmental factors. The risk of developing endometriosis for a first-degree relative is five times higher than in the general population (NP2). Identification of genetic variants involved in the disease has no implication for clinical practice for the moment. The role of environmental factors, particularly endocrine disrupters, is plausible but not demonstrated. Literature review does not support the progression of endometriosis over time, either in terms of the volume or the number of the lesions (NP3). The risk of acute digestive occlusion or functional loss of a kidney in patients followed for endometriosis seems exceptional. These complications were revealing the disease in the majority of cases. IVF does not increase the intensity of pain associated with endometriosis (NP2). There is few data on the influence of pregnancy on the lesions, except the possibility of a decidualization of the lesions that may give them a suspicious aspect on imaging. The impact of endometriosis on pregnancy is debated. There is an epidemiological association between endometriosis and rare subtypes of ovarian cancer (endometrioid and clear cell carcinomas) (NP2). However, the relative risk is moderate (around 1.3) (NP2) and the causal relationship between endometriosis and ovarian cancer is not demonstrated so far. Considering the low incidence of endometriosis-associated ovarian cancer, there is no argument to propose a screening or a risk reducing strategy for the patients.

Circulating Neutrophil Extracellular Traps Are Elevated in Patients With Deep Infiltrating Endometriosis

Neutrophil extracellular traps (NETs) have been described to be related to the pathogenesis of inflammatory and autoimmune conditions. Endometriosis is currently considered a chronic inflammatory condition. Therefore, we performed a preliminary case-control study to compare the circulating plasma NET levels in patients with surgically confirmed endometriosis (E group, n = 82) and those of patients without surgical findings of endometriosis (C group, n = 35). Venous blood samples were obtained at the time of surgery. Circulating plasma NET levels were assessed as histone-DNA complexes (ie, nucleosomes) by a quantitative sandwich enzyme-linked immunosorbent assay. The results were expressed in arbitrary units. Circulating plasma NET levels were significantly higher in the E group compared with the C group (median [25th; 75th percentiles]): E group: 0.734 [0.484; 1.363]; C group: 0.541 [0.411; 0.653]; P = .005). The subanalysis of E group patients with deep infiltrating endometriosis (DIE group) or without DIE (non-DIE group) showed that plasma NET levels were higher in the DIE group ( P = .02). No differences were observed in NET levels among patients with and without severe pelvic pain or in patients with and without infertility, regardless of the presence of endometriotic lesions. Therefore, our study shows significantly higher NET levels in patients with endometriosis, which seem to be attributed to increased levels in the subgroup of patients with DIE, suggesting that the presence of elevated circulating plasma NET levels may reflect an inflammatory status in this gynecological condition. Further research is warranted to confirm our findings and to assess the exact role of NETs in the pathophysiological mechanisms of endometriosis.

Treg and NK cells related cytokines are associated with deep rectosigmoid endometriosis and clinical symptoms related to the disease

The aim of this study was to evaluate Treg and NK cells related cytokines in deep infiltrating endometriosis lesions and its relationship with clinical symptoms of the disease. mRNA expression of Transforming Growth Factor Beta (TGFB), Interleukin (IL)10, Interferon Gamma (IFNG), IL7, and IL15 was analyzed by Real-Time PCR in eutopic endometrium and rectosigmoid lesions from 11 women with deep infiltrating endometriosis and in eutopic endometrium from 11 healthy women. IL10, IFNG, and IL7 expression was significantly higher in endometriotic bowel lesions than in eutopic endometrium from women with endometriosis. IL10 and TGFB expression was significantly higher in endometriotic bowel lesions than in eutopic endometrium from healthy women. In addition, TGFB and IL15 levels correlated positively with deep dyspareunia and cyclic dyschezia, respectively, while IL7 levels correlated negatively with dysmenorrhea. Deep infiltrating rectosigmoid endometriosis displays alterations in Treg and NK cells related cytokine, and TGFB, IL7 and IL15 expression is related with dyspareunia, dysmenorrhea and cyclic dyschezia, respectively, in patients with the disease.

Novel TRERF1 mutations in Chinese patients with ovarian endometriosis

Endometriosis is an estrogen-dependent precancerous lesion exhibiting frequently perturbed level of steroid hormones and transcriptional‑regulating factor 1 (TRERF1) has a crucial role in the production of steroid hormones including estrogen. Endometriosis has previously been revealed to be a precancerous lesion that harbors somatic mutations in cancer‑associated genes. Therefore, the authors of the present study hypothesize that TRERF1 aberrations may be involved in the development of endometriosis. In the present study, endometriotic lesions and paired blood samples from 92 individuals with ovarian endometriosis were analyzed for the potential presence of TRERF1 mutations by sequencing the entire coding region and the corresponding intron‑exon boundaries of the TRERF1 gene. Two heterozygous missense somatic mutations [c.3166A>C (p.K1056Q) and c.3187 G>A (p.G1063R)] in the TRERF1 gene were identified in two out of 92 ectopic endometria (2.2%), to the best of our knowledge, these mutations have not been previously reported. From the two samples with TRERF1 mutations, one sample was from a 42‑year‑old patient also diagnosed with uterine leiomyoma and the other mutation was identified in a 36‑year‑old woman exhibiting no other apparent gynecological conditions. The evolutionary conservation analysis and in silico prediction of these TRERF1 mutations suggested that they may be pathogenic. To the best of our knowledge, the present study was the first to identify 2 novel, potentially 'disease‑causing' TRERF1 somatic mutations in the endometriotic lesions in 2 out of 92 patients with ovarian endometriosis; therefore, TRERF1 mutations may be involved in the pathogenesis of ovarian endometriosis.

Endometriosis and endometriosis-associated cancers: new insights into the molecular mechanisms of ovarian cancer development

Endometriosis is a fascinating disease that we strive to better understand. Molecular techniques are shedding new light on many important aspects of this disease: from pathogenesis to the recognition of distinct disease variants like deep infiltrating endometriosis. The observation that endometriosis is a cancer precursor has now been strengthened with the knowledge that mutations that are present in endometriosis-associated cancers can be found in adjacent endometriosis lesions. Recent genomic studies, placed in context, suggest that deep infiltrating endometriosis may represent a benign neoplasm that invades locally but rarely metastasises. Further research will help elucidate distinct aberrations which result in this phenotype. With respect to identifying those patients who may be at risk of developing endometriosis-associated cancers, a combination of molecular, pathological, and inheritance markers may define a high-risk group that might benefit from risk-reducing strategies.

Interleukin-33 modulates inflammation in endometriosis

Endometriosis is a debilitating condition that is categorized by the abnormal growth of endometrial tissue outside the uterus. Although the pathogenesis of this disease remains unknown, it is well established that endometriosis patients exhibit immune dysfunction. Interleukin (IL)-33 is a danger signal that is a critical regulator of chronic inflammation. Although plasma and peritoneal fluid levels of IL-33 have been associated with deep infiltrating endometriosis, its contribution to the disease pathophysiology is unknown. We investigated the role of IL-33 in the pathology of endometriosis using patient samples, cell lines and a syngeneic mouse model. We found that endometriotic lesions produce significantly higher levels of IL-33 compared to the endometrium of healthy, fertile controls. In vitro stimulation of endometrial epithelial, endothelial and endometriotic epithelial cells with IL-33 led to the production of pro-inflammatory and angiogenic cytokines. In a syngeneic mouse model of endometriosis, IL-33 injections caused systemic inflammation, which manifested as an increase in plasma pro-inflammatory cytokines compared to control mice. Furthermore, endometriotic lesions from IL-33 treated mice were highly vascularized and exhibited increased proliferation. Collectively, we provide convincing evidence that IL-33 perpetuates inflammation, angiogenesis and lesion proliferation, which are critical events in the lesion survival and progression of endometriosis.

Diagnostic and treatment guidelines for gastrointestinal and genitourinary endometriosis

Endometriosis is commonly misdiagnosed, even among many experienced gynecologists. Gastrointestinal and genitourinary endometriosis is particularly difficult to diagnose, and is commonly mistaken for other pathologies, such as irritable bowel syndrome, interstitial cystitis, and even psychological disturbances. This leads to delays in diagnosis, mismanagement, and unnecessary testing. In this review, we will discuss the diagnosis and management of genitourinary and gastrointestinal endometriosis. Medical management may be tried first, but often fails in cases of urinary tract endometriosis. This is particularly important in cases of ureteral endometriosis because silent obstruction can lead to eventual kidney failure. Thus, we recommend complete surgical treatment in these cases. Bladder endometriosis may be managed more conservatively, and only if symptomatic, because these rarely lead to significant morbidity. In cases of bowel endometriosis, we recommend medical management first in all cases, and the least invasive surgical management only if medical treatment fails. This is due to the extensive nervous and vasculature supply to the lower rectum. Injury to these nerves and vessels can cause significant complications and postoperative morbidity.

HOXB4 Immunoreactivity in Endometrial Tissues From Women With or Without Endometriosis

Endometriosis is a common disease characterized by the presence of ectopic endometrial tissue. Although the pathogenesis of endometriosis remains unclear, several factors have been implicated, including the dysregulation of homeobox ( HOX) genes. Our objective was to investigate the localization and immunoreactivity of HOXB4 in endometrial tissues from women with or without endometriosis. We studied samples of eutopic endometrium (EE), endometriomas (Eoma), superficial endometriosis (SE), and deep infiltrating endometriosis (DIE) from 34 women with endometriosis, as well as eutopic endometrium from 38 women without endometriosis (EC). HOXB4 localization and immunoreactivity was assessed using immunohistochemistry and histoscore analysis. Data were analyzed with and without stratification by menstrual cycle phase. HOXB4 protein was present in the nuclei of endometrial glandular epithelial cells but not in stromal cells. HOXB4 immunoreactivity was reduced in DIE samples compared to all other groups. A smaller reduction in HOXB4 immunoreactivity was observed in SE samples compared to EC samples. HOXB4 immunoreactivity was significantly greater in proliferative compared to secretory phase samples in the EC group but not in EE, Eoma, or DIE groups. Among only proliferative phase samples, HOXB4 immunoreactivity was reduced in EE, Eoma, and DIE groups compared to EC. Based on these data, we suggest that an impaired capacity of eutopic and ectopic endometrial tissue to upregulate levels of HOXB4 during the proliferative phase may play a role in the pathogenesis of endometriosis and that further downregulation of HOXB4 may enhance ectopic implant invasiveness.

Oxidative Stress and Endometriosis: A Systematic Review of the Literature

Endometriosis is one of the most common gynaecologic diseases in women of reproductive age. It is characterized by the presence of endometrial tissue outside the uterine cavity. The women affected suffer from pelvic pain and infertility. The complex etiology is still unclear and it is based on three main theories: retrograde menstruation, coelomic metaplasia, and induction theory. Genetics and epigenetics also play a role in the development of endometriosis. Recent studies have put the attention on the role of oxidative stress, defined as an imbalance between reactive oxygen species (ROS) and antioxidants, which may be implicated in the pathophysiology of endometriosis causing a general inflammatory response in the peritoneal cavity. Reactive oxygen species are intermediaries produced by normal oxygen metabolism and are inflammatory mediators known to modulate cell proliferation and to have deleterious effects. A systematic review was performed in order to clarify the different roles of oxidative stress and its role in the development of endometriosis. Several issues have been investigated: iron metabolism, oxidative stress markers (in the serum, peritoneal fluid, follicular fluid, peritoneal environment, ovarian cortex, and eutopic and ectopic endometrial tissue), genes involved in oxidative stress, endometriosis-associated infertility, and cancer development.

The role of the B lymphocytes in endometriosis: A systematic review

The physiopathology of endometriosis is not completely understood and its progression is associated with a local and systemic inflammatory reaction. It is important to clarify the potential role of the immune system to better understand its implication in the pathogenesis of endometriosis, which includes the study of the role of B cells and antibodies. The aim of this study was to review the literature about the role of B lymphocytes in endometriosis. A search for "endometriosis", "B cells" and "B lymphocytes" in databases resulted in 140 citations; after applying inclusion and exclusion criteria, a total of 22 studies were assessed. The analyzed samples in the studies varied and different markers and techniques were used by the authors to evaluate the direct or indirect role of B lymphocytes in endometriosis. Most studies demonstrated increased number and/or activation of B cells while seven studies found no difference and two studies showed decreased number of B cells. Increased B lymphocytes and excessive production of autoantibodies in endometriosis have been described in the literature, but their role in the development of the disease is not well understood. Moreover, the association of these factors with clinical symptoms, location and severity of the disease has not been investigated. Further studies are necessary to clarify the role of B cells in the development of endometriosis and propose new therapeutic strategies such as the use of drugs that target these cells.

Alteration of Nrf2 and Glutamate Cysteine Ligase expression contribute to lesions growth and fibrogenesis in ectopic endometriosis

The redox-sensitive nuclear factor erythroid-derived 2-like 2 (NRF2) controls endogenous antioxidant enzymes' transcription and protects against oxidative damage which is triggered by inflammation and known to favor progression of endometriosis. Glutamate Cysteine Ligase (GCL), a target gene of NRF2, is the first enzyme in the synthesis cascade of glutathione, an important endogenous antioxidant. Sixty-one patients, with thorough surgical examination of the abdominopelvic cavity, were recruited for the study: 31 with histologically-proven endometriosis and 30 disease-free women taken as controls. Expressions of NRF2 and GCL were investigated by quantitative RT-PCR and immunohistochemistry in eutopic and ectopic endometria from endometriosis-affected women and in endometrium of disease-free women. Ex vivo stromal and epithelial cells were extracted and purified from endometrial and endometriotic biopsies to explore expression of NRF2 and GCL in both stromal and epithelial compartments by western blot. Finally, in order to strengthen the role of NRF2 in endometriosis pathogenesis, we evaluated the drop of NRF2 expression in a mouse model of endometriosis using NRF2 knockout (NRF2^-/-) mice. The mRNA levels of NRF2 and GCL were significantly lower in ectopic endometria of endometriosis-affected women compared to eutopic endometria of disease-free women. The immunohistochemical analysis confirmed the decreased expression of both NRF2 and GCL in ectopic endometriotic tissues compared to eutopic endometria of endometriosis-affected and disease-free women. Immunoblotting revealed a significant decreased of NRF2 and GCL expression in epithelial and stroma cells from ectopic lesions of endometriosis-affected women compared to eutopic endometria from controls. Using a murine model of endometriosis, NRF2^-/- implants were more fibrotic compared to wild-type with an increased weight and volume. These findings indicate that expression of the transcription factor NRF2 and its effector GCL are both profoundly deregulated in endometriotic lesions towards increased growth and fibrogenetic processes.

p38 Mitogen-Activated Protein Kinase is Involved in the Pathogenesis of Endometriosis by Modulating Inflammation, but not Cell Survival

BACKGROUND

Local pro-inflammatory environment and enhanced cell survival contribute to the endometriosis development. A serine/threonine kinase p38 mitogen-activated protein kinase (MAPK) mediates intracellular signaling of cytokine production, cell proliferation, and apoptosis in different cell types. The current study compares p38 MAPK activity in normal endometrium and endometriosis, and assesses role(s) of p38 MAPK on cytokine production and cell survival in endometriosis.

METHODS

Immunohistochemical levels of total and phosphorylated (active) p38 MAPK as well as its correlation with interleukin 8 (IL-8) expression, and cell proliferation and apoptosis were compared in normal human endometrium and endometriosis. The action of p38 MAPK on pro-inflammatory cytokine-induced IL-8 and monocyte chemotactic protein (MCP)-1 expression in endometriotic cells were assessed by enzyme-linked immunosorbent assay. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide cell survival, 5-bromo-2'-deoxyuridine incorporation, and Terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end labeling assays were used to determine the function of p38 MAPK in cultured human endometriotic stromal cell proliferation and apoptosis.

RESULTS

p38 MAPK activity was significantly higher in both eutopic and ectopic endometria compared to normal endometria during late proliferative and early secretory phases ( P < .05). Increased p38 MAPK activity in endometriotic cells correlated with IL-8 expression (Pearson correlation coefficient r = 0.83, P < .01), but not with apoptosis in vivo. The pro-inflammatory cytokines IL-1β and tumor necrosis factor (TNF)-α induced activation of p38 MAPK. Inhibition of p38 MAPK activity blocked IL-1β and TNF-α-induced IL-8 and MCP-1 secretion in cultured endometriotic stromal cells ( P < .05), but did not impact on endometriotic cell survival.

CONCLUSIONS

These results suggest that rather than modulating cell survival, increased p38 MAPK activity in endometriotic cells contributes to the pathogenesis of endometriosis by promoting the local inflammatory milieu.

Histological and Immunohistochemical Characterization of the Similarity and Difference Between Ovarian Endometriomas and Deep Infiltrating Endometriosis

Ovarian endometrioma (OMA) and deep infiltrating endometriosis (DIE) have long been recognized to have different histology and, as such, postulated to be 2 separate disease entities. Few studies, however, have attempted to elucidate the causes for their differences. Making use of ectopic endometrial tissue samples from 25 and 20 women with OMA and DIE, respectively, and control endometrial tissue samples from 25 women without endometriosis, we conducted an immunohistochemical analysis to evaluate the expression of a group of carefully chosen markers for epithelial-mesenchymal transition (EMT), fibroblast-to-myofibroblast transdifferentiation (FMT), smooth muscle metaplasia (SMM), fibrosis, vascularity, hormonal receptors, and proteins involved in epigenetic modifications. We found that both OMA and DIE lesions exhibited the same cellular changes consistent with EMT, FMT, SMM, and fibrosis as already shown in animal models. Compared to OMA, DIE lesions underwent more thorough and extensive EMT, FMT, and SMM and, consequently, displayed significantly higher fibrotic content but less vascularity. The 2 conditions also showed different expression levels of hormonal receptors. Both OMA and DIE lesions, especially the latter, showed significantly higher staining of enhancer of zeste homolog 2, H3K9me3, and H3K27me3 than that of control endometrium, suggesting progressive epigenetic changes concomitant with cellular ones. Finally, proteins that are known to be involved in fibrogenesis, such as thymocyte differentiation antigen 1 and peroxisome proliferator-activated receptor γ , were also aberrantly expressed under both conditions. The many similarities shared by both OMA and DIE indicate that the 2 conditions may actually share the same pathogenesis/pathophysiology. Their differences, however, suggest that the source of these differences may result from the different lesional microenvironments.

Deep Infiltrating Endometriosis-Urinary Tract Involvement and Predictive Factors for Major Surgery

OBJECTIVE

To evaluate urinary tract involvement by deep infiltrating endometriosis as well as the surgical treatment and existence of predictive factors for major urologic surgery.

METHODS

We conducted a retrospective analysis of 656 women submitted to surgery for endometriosis, of which 28 patients underwent minor or major surgery for deep infiltrating endometriosis involving the urinary tract, with a mean age of 38 ± 6.9 years (27-50) at diagnosis. Clinical data, surgeries performed, and complications were analyzed. Minor surgery was defined by endoscopic surgery or insertion of a percutaneous nephrostomy catheter, and major surgery included open or laparoscopic procedures.

RESULTS

Endometriomas affected the ureter in 13 (46.4%), the bladder in 11 (39.3%), and both structures in 4 (14.3%) patients. Twelve (42.9%) patients had decreased renal function, and ureteral involvement was predictive of renal function loss (P = .034). Minor surgeries were performed in most women with isolated bladder involvement and in 12 (42.9%) patients with ureteral infiltration. Patients with ureteric involvement underwent major surgeries more often (n = 12 vs n = 3; P = .025) and had longer hospitalization (8.2 vs 3.1 days, P = .05). After a mean follow-up of 36.3 (1-102) months, there was no bladder involvement recurrence. The most common complication was ureteral stenosis (Clavien-Dindo grade IIIb) in 3 (10.7%) patients.

CONCLUSION

Surgery is highly successful in most cases. Patients with ureteric involvement are more likely to lose kidney function, undergo major surgery, and have longer hospitalization.

To operate or not to operate on women with deep infiltrating endometriosis (DIE) before in vitro fertilization (IVF)

Deep infiltrating endometriosis (DIE) can cause infertility and pelvic pain. There is little evidence of a clear connection between DIE and infertility, and the absolute benefits of surgery for DIE have not been established. This paper aimed to review the current literature on the effect of surgery for DIE on fertility, pregnancy, and IVF outcomes. Clinicians should bear in mind that a comprehensive clinical history is useful to identify patients at risk for endometriosis, although many women remain asymptomatic. Imaging can be useful to plan surgery. The effect of surgery on the fertility of women with DIE remains unanswered due to the heterogeneous nature of the disease and the lack of trials with enough statistical power and adequate follow-up. Surgery is not recommended when the main goal is to treat infertility or to improve IVF results. Decisions should be tailored according to the individual needs of each woman. Patients must be provided information on the potential benefits, harm, and costs of each treatment alternative, while the medical team observes factors such as presence of pelvic pain, patient age, lesion location, and previous treatments. In this scenario, management by a multidisciplinary endometriosis team is a key step to achieving successful outcomes.

Cancer-Associated Mutations in Endometriosis without Cancer

BACKGROUND

Endometriosis, defined as the presence of ectopic endometrial stroma and epithelium, affects approximately 10% of reproductive-age women and can cause pelvic pain and infertility. Endometriotic lesions are considered to be benign inflammatory lesions but have cancerlike features such as local invasion and resistance to apoptosis.

METHODS

We analyzed deeply infiltrating endometriotic lesions from 27 patients by means of exomewide sequencing (24 patients) or cancer-driver targeted sequencing (3 patients). Mutations were validated with the use of digital genomic methods in microdissected epithelium and stroma. Epithelial and stromal components of lesions from an additional 12 patients were analyzed by means of a droplet digital polymerase-chain-reaction (PCR) assay for recurrent activating KRAS mutations.

RESULTS

Exome sequencing revealed somatic mutations in 19 of 24 patients (79%). Five patients harbored known cancer driver mutations in ARID1A, PIK3CA, KRAS, or PPP2R1A, which were validated by Safe-Sequencing System or immunohistochemical analysis. The likelihood of driver genes being affected at this rate in the absence of selection was estimated at P=0.001 (binomial test). Targeted sequencing and a droplet digital PCR assay identified KRAS mutations in 2 of 3 patients and 3 of 12 patients, respectively, with mutations in the epithelium but not the stroma. One patient harbored two different KRAS mutations, c.35G→T and c.35G→C, and another carried identical KRAS c.35G→A mutations in three distinct lesions.

CONCLUSIONS

We found that lesions in deep infiltrating endometriosis, which are associated with virtually no risk of malignant transformation, harbor somatic cancer driver mutations. Ten of 39 deep infiltrating lesions (26%) carried driver mutations; all the tested somatic mutations appeared to be confined to the epithelial compartment of endometriotic lesions.

Ureteral endometriosis: A systematic literature review

Introduction:

Ureteral endometriosis is a rare disease affecting women of childbearing age which presents with nonspecific symptoms and it may result in severe morbidity. The aim of this study was to review evidence about incidence, pathogenesis, clinical presentation, diagnosis, and management of ureteral endometriosis.

Materials and Methods:

PubMed Central database was searched to identify studies reporting cases of ureteral endometriosis. “Ureter” or “Ureteral” and “Endometriosis” were used as key words. Database was searched for articles published since 1996, in English without restrictions regarding the study design.

Results:

From 420 studies obtained through database search, 104 articles were finally included in this review, including a total of 1384 patients with ureteral endometriosis. Data regarding age, location, pathological findings, and interventions were extracted. Mean patients' age was 38.6 years, whereas the therapeutic arsenal included hormonal, endoscopic, and/or surgical treatment.

Conclusions:

Ureteral endometriosis represents a diagnostic and therapeutic challenge for the clinicians and high clinical suspicion is needed to identify it.

Euterpe oleracea Extract (Açaí) Is a Promising Novel Pharmacological Therapeutic Treatment for Experimental Endometriosis

This study investigated the therapeutic potential of Euterpe oleracea extract (açaí) on the growth and survival of endometriotic lesions using an experimental model. Twenty female Sprague-Dawley rats were randomized into two groups after the implantation and establishment of autologous endometrium onto the peritoneum abdominal wall and treated with 200 mg/kg hydroalcoholic solution extract from açaí stone or vehicle via gastric tube for 30 consecutive days. Body weight, lesion surface areas, histological and immunohistochemistry analyses of vascular endothelial growth factor (VEGF), VEGF receptor-2 (VEGFR-2), metalloproteinase-9 (MMP-9), cyclooxygenase-2 (COX-2) and F4-80 were performed. Levels of VEGF, VEGFR-2, MMP-9 and COX-2 mRNA were measured. Flow cytometry of F4-80 was performed, and ELISA immunoassays measured prostaglandin E₂ (PGE₂), VEGF and nitric oxide (NO) and concentrations. Macrophage cell line J774.G8 was treated with 10, 20, and 40 μg/mL of açaí for 24, 48 and 72 h, and cell viability was measured using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assays. Açaí treatment significantly decreased the implant size, and histological examination indicated atrophy and regression. A reduction in immunostaining and mRNA expression of VEGF, MMP-9 and COX-2 was observed, and F4-80 was lower in the treated group than the control group. The treated group also exhibited lower concentrations of PGE₂, VEGF and NO compared to the control group. Macrophages cells treated with 20 and 40 μg/ml of açaí reduced cell viability in about 50% after 24, 48 and 72 h. Our results suggest that açaí effectively suppressed the establishment and growth of endometriotic lesions, and this agent is a promising novel pharmacological therapeutic treatment for endometriosis.

Localization of TrkB and p75 receptors in peritoneal and deep infiltrating endometriosis: an immunohistochemical study

BACKGROUND

The roles of the neurotrophins NGF (Neurotrophic growth factor) and BDNF (brain-derived neurotrophic factor) in neuronal growth and development are already known. Meanwhile, the neurotrophin receptors TrkA (tropomyosin related kinase A), TrkB, and p75 are important for determining the fate of cells. In endometriosis, this complex system has not been fully elucidated yet. The aim of this study was to evaluate the expression and location of these neurotrophins and their receptors in peritoneal (PE) and deep infiltrating endometriotic (DIE) tissues and to measure and compare the density of nerve fibers in the disease subtypes.

METHODS

PE lesions (n = 20) and DIE lesions (n = 22) were immunostained and analyzed on serial slides with anti-BDNF, -NGF, -TrkA, -TrkB, -p75,-protein gene product 9.5 (PGP9.5, intact nerve fibers) and -tyrosine hydroxylase (TH, sympathetic nerve fibers) antibodies.

RESULT

There was an equally high percentage (greater than 75 %) of BDNF-positive immunostaining cells in both PE and DIE. TrkB (major BDNF receptor) and p75 showed a higher percentage of immunostaining cells in DIE compared to in PE in stroma only (p < 0.014, p < 0.027, respectively). Both gland and stroma of DIE lesions had a lower percentage of NGF-positive immunostaining cells compared to those in PE lesions (p < 0.01 and p < 0.01, respectively), but there was no significant reduction in immunostaining of TrkA in DIE lesions. There was no difference in the mean density of nerve fibers stained with PGP9.5 between PE (26.27 ± 17.32) and DIE (28.19 ± 33.15, p = 0.8). When we performed sub-group analysis, the density of nerves was significantly higher in the bowel DIE (mean 57.33 ± 43.9) than in PE (mean 26.27 ± 17.32, p < 0.01) and non-bowel DIE (mean 14.6. ± 8.6 p < 0.002).

CONCLUSIONS

While the neurotrophin BDNF is equally present in PE and DIE, its receptors TrkB and p75 are more highly expressed in DIE and may have a potential role in the pathophysiology of DIE, especially in promotion of cell growth. BDNF has a stronger binding affinity than NGF to the p75 receptor, likely inducing sympathetic nerve axonal pruning in DIE, resulting in the lower nerve fiber density seen.

Comprehensive study of angiogenic factors in women with endometriosis compared to women without endometriosis

OBJECTIVE

Endometriosis is a benign gynaecological disease, affecting women during their reproductive years. Angiogenesis represents a crucial step in the pathogenesis of endometriosis, because endometriotic lesions require neovascularization. In this study several angiogenesis-related genes have been studied in the context of endometriosis. Some of the analyzed angiogenic factors as well as their interactions were studied the first time regarding a possible association with endometriosis.

STUDY DESIGN

This case-control study consisted of 205 biopsies of 114 patients comprising 61 endometriosis patients and 53 control patients. Among them in 29 cases paired samples were obtained. VEGFA, VEGFR2, HIF1A, HGF, NRP1, PDGFB, FGF18, TNFα, TGFB2, EPHB4, EPO and ANG mRNA expression was analyzed by qRT-PCR in ectopic tissue samples, in eutopic endometrium of women with and without endometriosis, and in unaffected peritoneum of women with and without endometriosis.

RESULTS

VEGFR2, HIF1A, HGF, PDGFB, NRP1 and EPHB4 are overexpressed in ectopic lesions compared to eutopic tissues. VEGFR2, HGF, PDGFB, NRP1, and EPHB4 showed highest mRNA levels in peritoneal implants, in contrast HIF1A showed the highest expression in ovarian endometriomas. Correlation analyses of angiogenic factors in ectopic lesions revealed the strongest associations between VEGFR2, PDGFB, and EPHB4. We further showed a significant upregulation of VEGFR2, HIF1A and EPHB4 in eutopic endometrium of women with endometriosis compared to that of controls and a trend towards upregulation of HGF. Additionally, a significant downregulation for HIF1A, HGF and EPHB4 was observed in unaffected peritoneal tissues of women with endometriosis compared to controls.

CONCLUSION

We identified new genes (EPHB4 and NRP1) that may contribute to angiogenesis in endometriosis beside known factors (VEGFA, VEGFR2, HIF1A, HGF, and PDGFB). Correlation studies revealed the putative importance of EBHB4 in association with endometriosis. Our analyses support preliminary reports that angiogenic factors seem to be differently expressed in peritoneal implants, ovarian endometriomas and deep infiltrating endometriosis. Our observation that angiogenic factors are differently expressed in the unaffected peritoneum of women with endometriosis compared to women without endometriosis underlines the importance of the peritoneum in the establishment of endometriosis.

Effects of cisplatin and letrozole on surgically induced endometriosis and comparison of the two medications in a rat model

This study was to investigate the effects of cisplatin (CDDP) and letrozole on surgically induced endometriosis and comparison of the two drugs in a rat model. Endometriosis was surgically induced by autologous transplantation of endometrial pieces. Thirty model rats were divided into three groups, randomly. Group 1 (n=10) served as control and received no medication. Group 2 (n=10) received 0.2mg/kg/day of oral letrozole. Group 3 (n=10) received 35mg/m(2) CDDP via peritoneal perfusion every four days. All the rats were treated for 24days. The growth and histologic score of the implants were evaluated. The proliferation- and angiogenesis-associated proteins were assessed using immunohistochemistry and western blotting. The serum sex hormones were assayed using ELISA. After the medication, the growth and histologic score of the implants were significantly lower in the 2 and 3 groups than in the control group. The protein expressions of vascular endothelial growth factor (VEGF), aromatase P450 (P450arom), transforming growth factor-beta (TGF-β), and matrix metalloproteinase (MMP)-2, were significantly lower in groups 2 and 3 than in the control group. Further, the P450arom level was lower in the letrozole group than in the CDDP group. The TGF-β and MMP-2 levels were lower in the CDDP group than in the letrozole group. Serum T level was significantly higher in the letrozole group, and serum E2 level was lower in the letrozole group. In conclusion, cisplatin and letrozole caused similar regression of the implants in the endometriosis model rats. But their effects on the proliferation- and angiogenesis-associated protein expressions and the serum sex hormone levels were different. Cisplatin and letrozole might cause the effects in the endometriotic foci through different mechanism.

Urocortin and corticotrophin-releasing hormone receptor type 2 mRNA are highly expressed in deep infiltrating endometriotic lesions

Ovarian endometrioma (OMA) and deep infiltrating endometriosis (DIE) are the most severe forms of endometriosis, but different pathogenetic mechanisms and clinical symptoms distinguish these two forms. Corticotrophin-releasing hormone (CRH) and urocortin (Ucn) are endometrial neuropeptides involved in tissue differentiation and inflammation. The expression of CRH, Ucn, Ucn2, CRH-receptors (type-1 and type-2) and inflammatory enzymes phospholipase-A2 group IIA (PLA2G2A) and cycloxygenase-2 (COX2) were evaluated in OMA (n = 22) and DIE (n = 26). The effect of CRH or Ucn on COX2 mRNA expression was evaluated in cultured human endometrial stromal cells. In DIE lesions, CRH, Ucn and CRH-R2 mRNA levels were significantly higher than in OMA (P < 0.01, P < 0.001 and P < 0.05, respectively); DIE lesions showed a higher expression of COX2 (P < 0.01) and PLA2G2A (P < 0.05) mRNA than OMA, which was positively correlated with CRH-R2 mRNA expression (P < 0.05). Intense immunostaining for CRH and Ucn was shown in DIE. Treatment of cultured endometrial stromal cells with Ucn significantly increased COX2 mRNA expression (P < 0.01); this effect was reversed by the CRH-R2 antagonist astressin-2B. In DIE, DIE lesions highly express neuropeptide and enzyme mRNAs, supporting a strong activation of inflammatory pathways.

Preoperative risk factors in recurrent endometrioma after primary conservative surgery

Objective

Endometriosis is a common gynecological disorder caused by ectopic implantation of endometrial glandular and stromal cells outside the uterine cavity. Among several types of endometriosis, endometrioma is the only subtype that could be determined preoperatively using pelvic ultrasonography, and guidelines recommend pathologic confirmation of endometrioma greater than 3 cm in diameter. However, although surgery is performed in cases of endometrioma, endometrioma has a high cumulative rate of recurrence. Therefore, because determining the possibility of recurrence before performance of initial surgery is important, we examined preoperative factors associated with recurrent endometrioma.

Methods

This was a retrospective, comparative study including 236 patients who visited the outpatient clinic between January 2009 and December 2011. Patients who were pathologically diagnosed with endometrioma were included in this study. They were followed up postoperatively and were divided into two groups according to presence of recurrent endometrioma.

Results

We examined associations between baseline factors and recurrent endometrioma. In multivariate analysis, dysmenorrhea and cyst septation were statistically significant after adjusting with age, parity, surgical staging and postoperative management. We examined cumulative recurrence free survival within cases of recurrent endometriosis, based on the presence of inner cyst septation. The cumulative recurrence free survival was lower in cases with septation.

Conclusion

Our study found that recurrent endometrioma is more likely in patients with inner cyst septation and the recurrence occurred within a shorter duration of time than in patients without inner cyst septation on preoperative ultrasonography. Therefore intensive caution and postoperative long term medical therapy would be appropriate in patients with inner cyst septation on preoperative ultrasonography before undergoing primary surgery for endometrioma.

Postoperative hormonal therapy after surgical excision of deep endometriosis

The clinical management of women with deep peritoneal endometriosis remains controversial. The debate focuses mainly on the precise role of hormonal medical treatment and surgery and on the most suitable surgical technique to be used. In particular, considering the risks of second-line surgery, prevention of recurrences after first-line surgery is a priority in this context. Post-surgical medical therapy has been advocated to improve the effectiveness of surgery and prevent recurrences. However, adjuvant therapy, i.e. a short course of 3-6 months of hormonal therapy after surgery, has been proven to be of limited or no benefit for endometriosis in general and for deep peritoneal endometriosis in particular. On the other hand, two cohort studies suggest a beneficial effect of prolonged hormonal therapy after surgery for deep endometriosis. Even if this evidence is too weak to confidently advocate systematic administration of prolonged medical therapy after surgery, we argue in favour of this approach because of the strong association of deep endometriosis with other disease forms. In fact, women operated on for deep endometriosis may also face recurrences of endometriomas, superficial peritoneal lesions and pelvic pain in general. The demonstrated high effectiveness of prolonged postoperative therapy for the prevention of endometriomas' formation and dysmenorrhea recurrence should thus receive utmost consideration in the decision-making process.

rhTNFR: Fc Suppresses the Development of Endometriosis in a Mouse Model by Downregulating Cell Proliferation and Invasiveness

Tumor necrosis factor α (TNF-α), a proinflammatory cytokine, may play an important role in the pathogenesis of endometriosis; therefore, TNF-α inhibitors potentially have an effect on endometriosis. To investigate the effect of anti-TNF-α treatment on endometriosis, 2 TNF-α inhibitors: recombinant human TNF receptor: Fc fusion protein (rhTNFR: Fc) and TNF-α monoclonal antibody (TNF-α mAb) were used to treat human eutopic endometrial stromal cells (hESCs), and the effects on cell survival, cell cycle, and invasiveness were compared. It was found that rhTNFR: Fc suppressed the TNF-α-induced hESC survival and invasiveness but not TNF-α mAb. Recombinant human TNF receptor: Fc fusion protein decreased the S phase of hESC compared with the TNF-α-treated group. Then, we used a surgically induced mouse model of endometriosis to study the effect of rhTNFR: Fc treatment in vivo. The fluorescence intensity and the size of implanted endometriotic lesions in the mouse model were decreased by rhTNFR: Fc. In conclusion, rhTNFR: Fc suppresses hESC survival and invasiveness and decreases the fluorescence intensity and implant size in the mouse model of endometriosis.