Prognostic importance of atypical endometriosis with architectural hyperplasia versus cytologic atypia in endometriosis-associated ovarian cancer

Endometriosis-associated ovarian cancer: a different clinical entity

OBJECTIVE

To compare survival outcomes and patterns of recurrence between endometriosis-associated ovarian cancer patients and non-endometriosis-associated ovarian cancer patients.

METHODS

This retrospective study included data of consecutive patients with endometrioid or clear cell ovarian cancer treated at the Fondazione IRCCS Istituto Nazionale dei Tumori di Milano between January 2010 and June 2021. Patients were assigned to one of two groups according to the absence or presence of endometriosis together with ovarian cancer at final histological examination. Survival outcomes were assessed using Kaplan-Meier and Cox hazard models. Proportions in recurrence rate and pattern of recurrence were evaluated using the Fisher exact test.

RESULTS

Overall, 83 women were included in the endometriosis-associated ovarian cancer group and 144 in the non-endometriosis-associated ovarian cancer group, respectively. Patients included in the non- endometriosis-associated ovarian cancer group had a shorter disease-free survival than those in the endometriosis-associated ovarian cancer group (23.4 (range 2.0-168.9) vs 60.9 (range 4.0-287.8) months; p<0.001). Univariable and multivariable analyses showed that the association with endometriosis, previous hormonal treatment, early stage at presentation, and endometrioid histology were related to better disease-free survival in the entire study population. Similarly, patients in the non-endometriosis-associated ovarian cancer group had a shorter median (range) overall survival than those in the endometriosis-associated ovarian cancer group (54.4 (range 0.7-190.6) vs 77.6 (range 4.5-317.8) months; p<0.001). Univariable and multivariable analyses showed that younger age at diagnosis, association with endometriosis, and early stage at presentation were related to better overall survival. The recurrence rate was higher in the non-endometriosis-associated ovarian cancer group (63/144 women, 43.8%) than in the endometriosis-associated ovarian cancer group (17/83 women, 20.5%; p<0.001).

CONCLUSIONS

Endometriosis-associated ovarian cancer patients had significantly longer disease-free survival and overall survival than non-endometriosis-associated ovarian cancer patients, while the recurrence rate was higher in non-endometriosis-associated ovarian cancer patients.

Atypical Endometriosis: A Comprehensive Systematic Review of Pathological Patterns and Diagnostic Challenges

Endometriosis is a benign condition affecting women of reproductive age. A potential association with ovarian cancer has been documented. Atypical endometriosis (AE) is characterized by deviations from the typical microscopic appearance of endometriosis, including cytologic and architectural atypia. AE has been recognized as a potential precursor to endometriosis-associated ovarian cancers (EAOC), particularly endometrioid and clear cell subtypes. AE presents challenges in diagnosis due to its diverse clinical and pathological features, often requiring careful histological evaluation for accurate identification. Architectural AE, defined by localized proliferation of crowded glands with atypical epithelium resembling endometrial neoplasia, and cytologic AE, characterized by nuclear atypia within the epithelial lining of endometriotic cysts, are key subtypes. Immunohistochemical and molecular studies have revealed aberrant expression of markers such as Ki67, COX-2, BAF250a, p53, estrogen receptor, progesterone receptor, and IMP-3. Long-term follow-up studies suggest relatively low recurrence and malignant transformation rates among patients with AE, but uncertainties persist regarding its exact malignancy potential and optimal management strategies. Integration of artificial intelligence and shared molecular aberrations between AE and EAOC may enhance diagnostic accuracy. Continuous interdisciplinary collaboration and ongoing research efforts are crucial for a deeper understanding of the relationship between endometriosis and carcinogenesis, ultimately improving patient care and surveillance.

Immune pathway through endometriosis to ovarian cancer

Endometriosis is an estrogen-dependent inflammatory disease, defined by the presence of functional endometrial tissue outside of the uterine cavity. This disease is one of the main gynecological diseases, affecting around 10%-15% women and girls of reproductive age, being a common gynecologic disorder. Although endometriosis is a benign disease, it shares several characteristics with invasive cancer. Studies support that it has been linked with an increased chance of developing endometrial ovarian cancer, representing an earlier stage of neoplastic processes. This is particularly true for women with clear cell carcinoma, low-grade serous carcinoma and endometrioid. However, the carcinogenic pathways between both pathologies remain poorly understood. Current studies suggest a connection between endometriosis and endometriosis-associated ovarian cancers (EAOCs) via pathways associated with oxidative stress, inflammation, and hyperestrogenism. This article aims to review current data on the molecular events linked to the development of EAOCs from endometriosis, specifically focusing on the complex relationship between the immune response to endometriosis and cancer, including the molecular mechanisms and their ramifications. Examining recent developments in immunotherapy and their potential to boost the effectiveness of future treatments.

Endometriosis-Associated Ovarian Cancer: From Molecular Pathologies to Clinical Relevance

Endometriosis is a chronic condition affecting reproductive-aged women, characterized by the growth of ectopic endometrial tissue. Despite being benign, endometriosis is associated with an increased risk of certain cancers, including endometriosis-associated ovarian cancer (EAOC). Ovarian cancer is rare, but more common in women with endometriosis, particularly endometrioid and clear-cell carcinomas. Factors such as hormonal imbalance, reproductive history, environmental exposures, and genetic predisposition contribute to the malignant transformation of endometriosis. Thus, understanding potential risk factors causing malignancy is crucial. Over the past few decades, various genetic mutations, microRNAs, as well as tumor microenvironmental factors have been identified, impacting pathways like PI3K/AKT/mTOR, DNA repair mechanisms, oxidative stress, and inflammation. Thus, this review aims to summarize molecular studies involved in EAOC pathogenesis as potential therapeutic targets. However, further research is needed to better understand the molecular and environmental factors driving EAOC development, to target the susceptibility of endometriotic lesions to malignant progression, and to identify effective therapeutic strategies.

Endometriosis in Menopausal Women-A New Age Is Coming? Literature Review

Endometriosis is a chronic inflammatory disease, characterized by the presence of ectopic endometrial tissue, that leads to dysmenorrhea, painful intercourse and infertility. The shift in paradigm from the previous belief that endometriosis exclusively impacts women of reproductive age has brought attention to the condition in both premenarchal and postmenopausal women. Currently, 2-4% of postmenopausal women have endometriosis. Many women experience menopausal symptoms during the peri- and postmenopausal periods and require extensive investigations and monitoring in order to avoid the recurrence of endometriosis symptoms or the risk of malignant transformation when treatment with menopausal hormones is elected. Our goal was to compile and present a clear and concise overview of the existing literature on postmenopausal endometriosis, offering an up-to-date and precise summary of the available information.

New insights about endometriosis-associated ovarian cancer: pathogenesis, risk factors, prediction and diagnosis and treatment

Previous studies have shown that the risk of malignant transformation of endometriosis in premenopausal women is approximately 1%, significantly impacting the overall well-being and quality of life of affected women. Presently, the diagnostic gold standard for endometriosis-associated ovarian cancer (EAOC) continues to be invasive laparoscopy followed by histological examination. However, the application of this technique is limited due to its high cost, highlighting the importance of identifying a non-invasive diagnostic approach. Therefore, there is a critical need to explore non-invasive diagnostic methods to improve diagnostic precision and optimize clinical outcomes for patients. This review presents a comprehensive survey of the current progress in comprehending the pathogenesis of malignant transformation in endometriosis. Furthermore, it examines the most recent research discoveries concerning the diagnosis of EAOC and emphasizes potential targets for therapeutic intervention. The ultimate objective is to improve prevention, early detection, precise diagnosis, and treatment approaches, thereby optimizing the clinical outcomes for patients.

Atypical Endometriosis: Comprehensive Characterization of Clinicopathologic, Immunohistochemical, and Molecular Features

Atypical endometriosis (A-EMS), defined by cytologic atypia and/or crowded glands resembling endometrial intraepithelial neoplasia, remains poorly understood. We aimed to refine the morphologic, immunohistochemical, and molecular features of A-EMS in an institutional series. Cases were identified through a structured search and reviewed by 2 pathologists. Immunohistochemistry and comprehensive sequencing using a panel 447-gene coverage were performed in suitable cases. A-EMS with synchronous and/or subsequent EMS-related neoplasia were compared with those without. Of 4598 EMS cases over an 11-yr period, 36 A-EMS were identified. The mean age at presentation was 46 (range 26-68) yr. Locations included the ovary (24, 66%), tubo-ovary (6, 17%), fallopian tube (3, 8%), and peritoneum (3, 8%). The mean size was 6.5 (range 0.5-40) mm. Cytologic atypia was mild in 4 (11%), moderate in 21 (58%), and severe in 11 (31%). Most lesions were partially or completely flat (28, 78%); of these, 66% showed hobnail nuclei. Crowded/cribriform and micropapillary/papillary patterns were seen in 11 (31%) and 16 (44%) A-EMS, respectively. Immunohistochemistry, performed in 33 A-EMS, showed wildtype p53 (100%) retained PMS2/MSH6 (100%), and positive estrogen receptor (97%, mean 65% cells), progesterone receptor (76%, mean 30% cells), and Napsin A (39%). Ki67 labelling was <1% to 10% (median 5%). Nine (25%) patients presented with concurrent or subsequent ipsilateral endometrioid, seromucinous, or clear cell neoplasia (4 borderline tumors and 4 carcinomas). The only A-EMS feature statistically more frequent in this subset was crowded/glands (6/9 vs. 2/27 A-EMS without, P =0.001 Fisher exact test). Sequencing showed pathogenic variants in 5 of 6 cases analyzed, involving ATM , BRCA2 , KRAS , AKT , CTNNB1 , PTEN , and ARID1A among other genes. In 2 cases, synchronous neoplasia showed an accumulation of additional variants. A-EMS is characterized by cytologic atypia and crowded architecture but low proliferation index, positive estrogen receptor, and normal p53 and MMR, which can be helpful in the distinction from malignancy. The prevalence of synchronous/subsequent tubo-ovarian neoplasia in our series was 25%, significantly higher than the reported 1% in conventional EMS. Moreover, A-EMS harbors genomic alterations seen in EMS-related tumors and shares pathogenic variants with synchronous ipsilateral neoplasia. Therefore, it is important to report A-EMS as currently defined and describe its architectural features, especially gland crowding as this appears to increase the risk of EMS-related epithelial neoplasia. Napsin-A is often positive in A-EMS and should be interpreted with caution.

Is ovarian cystectomy for atypical ovarian endometrioma safe?: A single center study

Ovarian atypical endometriosis (AE) is a premalignant lesion, and its potential to progress to endometriosis-associated ovarian cancer emphasizes its significance. However, the true risk of malignancy in AE remains unclear. Therefore, this study aimed to investigate the clinical outcomes of ovarian AE after ovarian cystectomy. We retrospectively reviewed the medical records and histopathological reports of 41 patients who had been diagnosed with ovarian AE between January 2011 and April 2020. We reviewed age, obstetric history, age at menarche, preoperative CA 125 level, C-reactive protein level, erythrocyte sedimentation rate, endometriosis stage, mean follow-up duration, postoperative hormonal therapy, and prognosis, including recurrence of endometriosis and malignant transformation. Among 41 patients with pathologically diagnosed ovarian AE, 26 were followed up after cystectomy only. The average follow-up period was 58.27 ± 33.22 months in cystectomy only patients. The mean age of the patients with cystectomy only versus that of patients with endometriosis-associated ovarian carcinoma was 32.73 ± 6.10 versus 48.29 ± 4.35 (P < .01) years. The preoperative CA 125 level was 115.63 ± 219.06 versus 225.75 ± 163.39 (P < .051) U/mL. Patients with endometriosis-associated ovarian carcinoma or other diseases and those who underwent oophorectomy were excluded. After surgery, hormone therapy was administered to 22 of 26 patients, and the remaining 4 patients were followed up without additional treatment. Endometriosis recurrence occurred in 5 patients, 1 of whom underwent second-line laparoscopic ovarian cystectomy. However, no malignant transformations were observed. Ovarian AE has a low possibility of malignant transformation. Conservative treatment is recommended after appropriate ovarian cystectomy, such as enucleation.

A Systematic Review of Atypical Endometriosis-Associated Biomarkers

Ovarian endometriosis may increase the risk of malignancy. Several studies have suggested atypical endometriosis as the direct precursor of endometriosis-associated ovarian cancer. We performed an advanced, systematic search of the online medical databases PubMed and Medline. The search revealed n = 40 studies eligible for inclusion in this systematic review. Of these, n = 39 were finally included. The results from included studies are characterized by high heterogeneity, but some consistency has been found for altered expression in phosphoinositide 3-kinase (PI3K)/AKT/mTOR pathway, ARID1a, estrogen and progesterone receptors, transcriptional, nuclear, and growth factors in atypical endometriosis. Although many targets have been proposed as biomarkers for the presence of atypical endometriosis, none of them has such strong evidence to justify their systematic use in clinical practice, and they all need expensive molecular analyses. Further well-designed studies are needed to validate the evidence on available biomarkers and to investigate novel serum markers for atypical endometriosis.

Predictive factors of endometriosis progression into ovarian cancer

BACKGROUND

In recent years, the endometriosis has overcome a noteworthy renaissance in the recognition of its potential. In certain patients, a demonstrable malignant progression of ectopic foci leading to development of ovarian cancer is seen. The knowledge of endometriosis overthrow background into endometriosis associated ovarian cancer is of paramount importance for selection of patients at risk. The goal of the presented study was to review a malignant potential of the endometriosis and to specify predictive factors of endometriosis progression into ovarian cancer. Altogether 189 patients were included in the study. Conventional cytogenetics as well as measurement of transcriptional activity of CTNNB1 (β-catenin) and HIF1A (HIF1-α) genes were prospectively studied in 60 endometriosis patients and 50 control group patients. The retrospective histopathological analysis was performed in 19 endometriosis associated ovarian cancer patients and 60 patients with histologically confirmed endometriosis.

RESULTS

Five endometriosis patients showed a deviation from normal cytogenetics finding without affecting of their phenotype. In 6 cases of endometriosis associated ovarian cancer ectopic endometrium was not confirmed. The remaining 13 cases demonstrated either benign or atypical endometriosis or even structures of borderline carcinoma. Atypical endometriosis was histologically confirmed in 20% of 60 endometriosis patients. Determination of gene expression (CTNNB1, HIF1A) formed two subgroups. Transcriptionally incipient endometriosis subgroup with insignificant genes expression compared to control group. In transcriptionally evident endometriosis subgroup were genes expressions significantly higher compared to control group (p < 0.01) as well as transcriptionally incipient endometriosis subgroup (p < 0.05).

CONCLUSIONS

Significant structural abnormalities of chromosomes are not included in genetic rigging of endometriosis patients. Atypical endometriosis represents a histopathologically detectable intermediate of endometriosis progression. Determination of genes expression CTNNB1 and HIF1A helps to allocate risk patients with endometriosis where more precise management is needed.

Is there a relationship in-between ovarian endometriosis and ovarian cancer? Immunohistochemical profile of four cases with coexisting ovarian endometriosis and cancer

Endometriosis (EMs) is a benign disease characterized by the presence of endometrial tissue outside the uterine cavity. EMs associated with ovarian cancer (OC) has a relative low incidence (5% to 10%), sometimes with evidence of a transition stage through atypical EMs (1.6% cases). We have assessed 135 consecutive patients with either EMs or OC and, out of them, our study reports on four cases of ovarian EMs and OC: two cases with endometrioid OC and two cases with high-grade serous OC (HGSOC). Cases with EMs and HGSOC are extremely rarely reported in the literature – we could find not more than 30 cases. The main objective of our research was to observe the possible similarities between EMs and OC. Secondly, we analyzed the differences between EMs associated with endometrioid OC and EMs associated with HGSOC. We evaluated them in terms of clinical status (age, stages of EMs and OC) and immunohistochemical (IHC) expression of estrogen receptor (ER), progesterone receptor (PR), Ki67, p53, p16, Wilms’ tumor 1 (WT1), cluster of differentiation (CD) 34 and CD10 immunomarkers – we could not find in the literature all these markers assessed, in the same time, to such samples. Our results indicated that there are no similarities between EMs and OC and no atypical EMs was identified in our cases. We recorded higher values of ER expression in EMs associated with HGSOC than in EMs associated with endometrioid OC. Higher values of ER expression were also recorded in OC than in endometriotic foci. There were no differences in proliferative rate of endometriotic foci associated with endometrioid OC, compared to EMs associated with HGSOC. An aberrant IHC expression for p53 protein and p16 protein was noted only in HGSOC. Also, a positive immunostaining for Wilms’ tumor 1 (WT1) was identified only in HGSOC. Higher values of microvessel density were recorded in OC but not in endometriotic foci. We concluded that there were no similarities between EMs and OC for the cases included in our study, but we noticed differences in terms of Ki67 index and also between hormonal receptors expression in EMs associated with HGSOC, comparing with EMs associated with endometrioid OCs. These results may represent a “brick” for future researches on the less understood EMs associated with type II of OCs, especially with HGSOC. Identifying the best marker, which can predict the risk of developing OC for the patients with EMs, may lead to discover new specific therapeutic agents and, therefore, a better, tailored, therapy.

Assessing CT imaging features combined with CEA and CA125 levels to identify endometriosis-associated ovarian cancer

PURPOSE

To improve the diagnosis and identification of ovarian clear cell carcinoma (CCC) and ovarian endometrioid carcinoma (EC), we evaluated CT imaging findings and cut-off values for CEA and CA125.

METHODS

The CT features and tumour markers (tumour size, location, morphology, composition, number of cysts, growth pattern of the mural nodules, mural nodule HWR, enhancement of the mural nodules, ascites, complications, CEA level, CA125 level) of 55 tumours in 52 patients with CCC, confirmed by surgery and pathology at the Yunnan Cancer Hospital from January 1, 2012 to December 30, 2018, were compared with those of 41 tumours in 36 patients with EC. All patients had a long history of endometriosis. Statistical analysis was performed using t test, chi-square test, Mann-Whitney U test, univariate analysis, multivariate logistic regression analysis and receiver-operating characteristic (ROC) curves.

RESULTS

CCC and EC presented as large oval or irregular mixed cystic-solid masses in the pelvic region, with moderately delayed enhancement of the solid components. There was a statistically significant difference between the number of cysts, the growth pattern of the mural nodules, the presence/absence of ascites, and the levels of CEA and CA125 (P < 0.05). Most CCCs had unilocular cysts, mural nodules that were polypoid structures, and no ascites (46/55, 33/55, 42/55); most ECs had multilocular cysts and broad-based nodular structures and were ascites positive (28/41, 31/41, 21/41). The CEA positive rate was lower in the CCC group than in the EC group (2/52, 3.8% versus 11/36, 30.6%, P < 0.05), and the CA125 positive rate was high in both the CCC and EC groups (44/52, 84.6% versus EC = 35/36, 97.2%, P = 0.118). The ROC curves revealed that when the values of CEA and CA125 were higher than the cut-off values (CEA = 3.270 µg/L, CA125 = 589.400 kU/L), the diagnostic efficiency of CEA was 0.723, and the diagnostic specificity of CEA was as high as 0.903.

CONCLUSIONS

The number of cysts, growth pattern of the mural nodules, presence/absence of ascites, and levels of CEA and CA125 were useful factors for distinguishing CCC from EC; the best cut-off values of CEA and CA125 for distinguishing CCC from EC were 3.270 and 589.40, respectively. These findings may be helpful for correctly diagnosing and identifying CCC and EC.

Clinical and Pathological Significance of Cellular Atypia in Endometriosis

Objective: To highlight the most frequent localization of ovarian endometriosis, the presence of atypical endometriosis, and recurrences. Retrospective review of 259 patients diagnosed with ovarian endometriosis treated at Tîrgu-Mures Emergency County Hospital, Obstetric Gynecology Clinic, between January 2014 and December 2018. Methods: Data were collected and analyzed for demographics, size of ovarian endometriotic cyst, and recurrences. Results: Out of 259 patients, 51 patients presented atypia, 20 on the right, 24 on the left, and seven patients were diagnosed with endometriosis with bilateral atypia. Higher susceptibility for left localization was noted. Thirty-nine patients (15.1%) presented recurrence. A statistically significant correlation (p = 0.006) was noted between patients with recurrence and atypia compared with those without atypia and endometriotic cysts larger than 7 cm. Patients with relapse under the age of 40 were noted to have mainly atypia with localization on the right (p = 0.025, OD = 4.107). Conclusions: The presence of endometrioma was not statistically significant correlated with left or right sided localization; recurrent endometriomas larger than 7 cm represents a risk for atypical endometriosis development. Recurrence and atypia appear more often in patients under the age of 40 and are right-sided. The total removal of the endometriomas can prevent the recurrence and subsequently the appearance of atypia and secondary neoplastic conditions.

Is dispositional optimism associated with endometriomas and deep infiltrating endometriosis?

INTRODUCTION

Endometriosis is a chronic painful condition characterized by high prognostic uncertainty, as well as the threat of infertility and emotional symptoms that may affect many aspects of women, including psychological characteristics like dispositional optimism. Considering the impact of endometriosis on psychological health and the paucity of papers on this topic, the aim of this study is to explore optimism and associated factors in endometriosis.

METHODS

A case-control study was performed on a group of 95 women with endometriosis and 156 controls. All participants completed the Life Orientation Test-Revised (LOT-R), a self-administered tool for assessing dispositional optimism. Pain severity, medication, gynecological and socio-demographic information was also collected.

RESULTS

Low optimism was observed for women with endometriosis compared to controls even after covariate adjustment (LOT-R global scores: 14.5 vs. 15.9 points, p = .045).

CONCLUSIONS

This study provides the first evidence that a personality dimension with many prognostic implications may be altered in women with endometriosis. Our findings highlight the importance of a broader understanding of this condition, treating this disorder from a biopsychosocial perspective and suggests the need for non-medical attention within a multidisciplinary team.

Ovarian endometriosis, a precursor of ovarian cancer: Histological aspects, gene expression and microRNA alterations (Review)

Ovarian endometriosis is a frequent chronic gynecological disease with an uncertain evolution regarding its progression or association with ovarian malignant lesions. The present review summarized the histological aspects, gene expression and microRNA (miRNA/miR) alterations associated with ovarian endometriosis and cancer and their possible interaction. The endometriosis-ovarian cancer interaction has been proposed by certain researchers as a single entity. Histological results indicated that endometriosis has been in different circumstances coexisting with ovarian cancer, with reference to endometrioid and clear cell carcinoma. Endometriosis with moderate and severe atypia can influence cell proliferation and architecture, resulting in a possible malignant transformation. Gene expression analysis indicated that the pathologies of both endometriosis and ovarian cancer are characterized by genetic instability from a molecular point of view, as several important genetic mutations, including ARID1A, PI3KCA, PTEN, BRCA1, BRCA2, TP53 and KRAS genes, were identified. miRNA alterations have been implicated in the regulation of gene expression. Common dysregulated miRNAs, such as miR-331, miR-335, miR-891, miR-548, miR-124, miR-148, miR-215, miR-192, miR-337, miR-153, miR-155, miR-144, miR-221 and miR-3688 were extensively investigated in understanding endometriosis and ovarian cancer evolution. From a combined viewpoint including histological aspects, gene expression and miRNA alterations, it is reasonable to speculate that endometriosis is associated with ovarian cancer. Ovarian endometriosis lesions may present a risk for ovarian malignant lesions, which supports a model of endometriosis as a malignant precursor. However, the endometriosis-ovarian cancer association is not widely accepted in the literature and additional studies are required to validate this association.

Endometriosis: A Comprehensive Review

Endometriosis is a relatively common condition in which endometrial tissue is established in locations outside the uterus where, like the eutopic endometrium, it responds to hormonal stimuli and develops internal bleeding, inflammation, and fibrosis. These changes are associated with chronic and often debilitating cyclic pain and infertility. The pathogenesis of endometriosis is multifactorial, and several theories have been proposed to explain it. These include retrograde menstruation, celomic metaplasia, embryologic rests, and lymphovascular spread. Hormones, immunologic status, and genetic factors may also play a role. In most patients, the disease involves pelvic organs, but rarely it may also extend to a large variety of distant locations in the body. Patients with ovarian endometriosis are at higher risk for developing ovarian carcinomas including endometrioid and clear cell carcinomas. Some of these carcinomas may arise in a background of structural and/or nuclear atypia within the endometriotic foci. There is no known cure for endometriosis and treatment mostly consists of managing chronic pain or infertility.

Malignant Transformation and Associated Biomarkers of Ovarian Endometriosis: A Narrative Review

This review focuses on pathogenesis of endometriosis, its possible biomarkers and role in endometriosis-associated ovarian cancer. We analyzed various databases to obtain new insights, theories, and biomarkers associated with endometriosis. There are several theories of endometriosis development and biomarker changes including atypical forms. A number of studies have attempted to establish specific, reliable biomarkers to help diagnose endometriosis and endometriosis-associated diseases on the basis of different pathogenetic pathways. Nevertheless, despite intensive research extending even to the molecular level, the origin, natural history, malignant transformation, and laboratory management of endometriosis and related diseases are not yet clearly defined. Therefore, early laboratory diagnoses of endometriosis, its atypical form, and endometriosis-associated ovarian tumors are important problems that require further study in the context of advanced therapeutic strategies to provide maximal health benefits to patients.

Interplay Between MicroRNAs and Oxidative Stress in Ovarian Conditions with a Focus on Ovarian Cancer and Endometriosis

Ovarian cancer and endometriosis are two distinct gynaecological conditions that share many biological aspects incuding proliferation, invasion of surrounding tissue, inflammation, inhibition of apoptosis, deregulation of angiogenesis and the ability to spread at a distance. miRNAs are small non-coding RNAs (19–22 nt) that act as post-transcriptional modulators of gene expression and are involved in several of the aforementioned processes. In addition, a growing body of evidence supports the contribution of oxidative stress (OS) to these gynaecological diseases: increased peritoneal OS due to the decomposition of retrograde menstruation blood facilitates both endometriotic lesion development and fallopian tube malignant transformation leading to high-grade serous ovarian cancer (HGSOC). Furthermore, as HGSOC develops, increased OS levels are associated with chemoresistance. Finally, continued bleeding within ovarian endometrioma raises OS levels and contributes to the development of endometriosis-associated ovarian cancer (EAOC). Therefore, this review aims to address the need for a better understanding of the dialogue between miRNAs and oxidative stress in the pathophysiology of ovarian conditions: endometriosis, EAOC and HGSOC.