Relationship of benign gynecologic diseases to subsequent risk of ovarian and uterine tumors

Pathogenesis of Endometriosis and Endometriosis-Associated Cancers

Endometriosis is a hormone-dependent, chronic inflammatory condition that affects 5-10% of reproductive-aged women. It is a complex disorder characterized by the growth of endometrial-like tissue outside the uterus, which can cause chronic pelvic pain and infertility. Despite its prevalence, the underlying molecular mechanisms of this disease remain poorly understood. Current treatment options are limited and focus mainly on suppressing lesion activity rather than eliminating it entirely. Although endometriosis is generally considered a benign condition, substantial evidence suggests that it increases the risk of developing specific subtypes of ovarian cancer. The discovery of cancer driver mutations in endometriotic lesions indicates that endometriosis may share molecular pathways with cancer. Moreover, the application of single-cell and spatial genomics, along with the development of organoid models, has started to illuminate the molecular mechanisms underlying disease etiology. This review aims to summarize the key genetic mutations and alterations that drive the development and progression of endometriosis to malignancy. We also review the significant recent advances in the understanding of the molecular basis of the disorder, as well as novel approaches and in vitro models that offer new avenues for improving our understanding of disease pathology and for developing new targeted therapies.

Genetic Links between Endometriosis and Endometriosis-Associated Ovarian Cancer-A Narrative Review (Endometriosis-Associated Cancer)

Endometriosis is a frequent, estrogen-dependent, chronic disease, characterized by the presence of endometrial glands and stroma outside of the uterine cavity. Although it is not considered a precursor of cancer, endometriosis is associated with ovarian cancer. In this review, we summarized the evidence that clear-cell and endometrioid ovarian carcinomas (endometriosis-associated ovarian carcinoma-EAOC) may arise in endometriosis. The most frequent genomic alterations in these carcinomas are mutations in the AT-rich interaction domain containing protein 1A (ARID1A) gene, a subunit of the SWI/SNF chromatin remodeling complex, and alterations in phosphatidylinositol 3-kinase (PI3K) which frequently coexist. Recent studies have also suggested the simultaneous role of the PTEN tumor-suppressor gene in the early malignant transformation of endometriosis and the contribution of deficient MMR (mismatch repair) protein status in the pathogenesis of EAOC. In addition to activating and inactivating mutations in cancer driver genes, the complex pathogenesis of EAOC involves multiple other mechanisms such as the modulation of cancer driver genes via the transcriptional and post-translational (miRNA) modulation of cancer driver genes and the interplay with the inflammatory tissue microenvironment. This knowledge is being translated into the clinical management of endometriosis and EAOC. This includes the identification of the new biomarkers predictive of the risk of endometriosis and cancer, and it will shape the precision oncology treatment of EAOC.

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.

Uterine leiomyomata claim rate estimates and demographic characteristics by county. Florida, 2010-2019

To describe the demographic characteristics and estimate the uterine leiomyomata claim rates (ULCRs) by women 18 years and older in Florida, we conducted a cross-sectional analysis of the 2010-2019 administrative claims for uterine leiomyomata and associated study variables (age, race, ethnicity, county of residence, anatomic site, length of stay, and additional diagnoses). ULCR ratios were estimated by race and ethnicity, using ULCR for non-Hispanic White women as the reference group. We identified 232,475 claims, most of which were among non-Hispanic White women in their forties. The overall ULCR estimate [95 percent CI] was 284.8 [284.21, 285.39] per 100,000 women 18 years and older, with a small, nonsignificant trend to increase over time (R2 = .310; p = .094). Black, Hispanic, and other women of color presented with higher ULCR ratios (4.84, 1.87, and 1.58, respectively). Urban counties had significantly higher ULCRs than suburban and rural counties. While non-Hispanic White women had the highest frequency of ULCRs, women of color-especially Black women-presented with significantly higher ULCR ratios. The epidemiologic profile of uterine leiomyomata in terms of age, race, ethnicity, and geographic location points to unmet healthcare needs among specific demographic and geographic groups of women in Florida.

Hypoxia-inducible Factor-1α and mTOR as a Potential Therapeutic Target in Endometriosis: An Immunohistochemical Study

BACKGROUND AND STUDY AIM

We aim to study the immunohistochemical expression of both hypoxia-inducible factor-1α (HIF-1α) and mammalian target of rapamycin (mTOR) in endometriosis to provide new evidence for a targeted endometriosis therapy.

PATIENTS AND METHODS

This study comprised 106 endometriotic cases diagnosed clinically and histopathologically. The immunohistochemical method was done to determine the expression of HIF-1α and mTOR.

RESULTS

Endometriotic glands showed significant cytoplasmic expression of both markers in patients with poor ovulation, severe endometriosis, and infertile for >2 years ( P <0.001). Also, patients with intense and worst pain show significant immunohistochemical expression of both markers ( P <0.001). There is a significant correlation between mTOR and HIF-1α expression in endometriotic tissue samples as P <0.001.

CONCLUSIONS

Our data suggest that both mTOR and its downstream target HIF-1α transcription factor are both disrupted in patients with endometriosis, which is consistent with aberrant activation of these pathways and their possible contribution to the pathogenesis of endometriosis. These results could offer a promising novel opportunity to be blocked therapeutically. As new management options need to be refined in particular in severe cases and infertile patients with endometriosis, therefore future studies are warranted to investigate treating endometriosis with mTOR inhibitors; the latter are already in clinical trials in phase III and IV, treating solid tumors as well as non-neoplastic disorders.

Racial Differences in the Association of Endometriosis and Uterine Leiomyomas With the Risk of Ovarian Cancer

OBJECTIVE

To evaluate associations between endometriosis and uterine leiomyomas with ovarian cancer risk by race and the effect of hysterectomy on these associations.

METHODS

We used data from four case-control studies and two case-control studies nested within prospective cohorts in the OCWAA (Ovarian Cancer in Women of African Ancestry) consortium. The study population included 3,124 Black participants and 5,458 White participants, of whom 1,008 Black participants and 2,237 White participants had ovarian cancer. Logistic regression was used to calculate odds ratios (ORs) and 95% CIs for the associations of endometriosis and leiomyomas with ovarian cancer risk, by race, stratified by histotype and hysterectomy.

RESULTS

The prevalences of endometriosis and leiomyomas were 6.4% and 43.2% among Black participants and 7.0% and 21.5% among White participants, respectively. Endometriosis was associated with an increased risk of endometrioid and clear-cell ovarian cancer in both racial groups (eg, OR for endometrioid tumors for Black and White participants 7.06 [95% CI 3.86-12.91] and 2.17 [95% CI 1.36-3.45], respectively, Phetereogeneity =.003). The association between endometriosis and ovarian cancer risk in White participants was stronger in those without hysterectomy, but no difference was observed in Black participants (all Pinteraction ≥.05). Leiomyomas were associated with an elevated risk of ovarian cancer only in those without hysterectomy in both Black (OR 1.34, 95% CI 1.11-1.62) and White (OR 1.22, 95% CI 1.05-1.41) participants (all Pinteraction ≥.05).

CONCLUSIONS

Black and White participants with endometriosis had a higher risk of ovarian cancer, and hysterectomy modified this association among White participants. Leiomyomas were associated with an increased risk of ovarian cancer in both racial groups, with hysterectomy modifying the risk in both groups. Understanding how racial differences in access to care and treatment options (eg, hysterectomy) may help guide future risk reduction strategies.

The Endometriotic Neoplasm Algorithm for Risk Assessment (e-NARA) Index Sheds Light on the Discrimination of Endometriosis-Associated Ovarian Cancer from Ovarian Endometrioma

BACKGROUND

Magnetic resonance (MR) relaxometry provides a noninvasive tool to discriminate endometriosis-associated ovarian cancer (EAOC) from ovarian endometrioma (OE) with high accuracy. However, this method has a limitation in discriminating malignancy in clinical use because the R2 value depends on the device manufacturer and repeated imaging is unrealistic. The current study aimed to reassess the diagnostic accuracy of MR relaxometry and investigate a more powerful tool to distinguish EAOC from OE.

METHODS

This retrospective study was conducted at our institution from December, 2012, to May, 2022. A total of 150 patients were included in this study. Patients with benign ovarian tumors (n = 108) mainly received laparoscopic surgery, and cases with suspected malignancy (n = 42) underwent laparotomy. Information from a chart review of the patients' medical records was collected.

RESULTS

A multiple regression analysis revealed that the age, the tumor diameter, and the R2 value were independent malignant predicting factors. The endometriotic neoplasm algorithm for risk assessment (e-NARA) index provided high accuracy (sensitivity, 85.7%; specificity, 87.0%) to discriminate EAOC from OE.

CONCLUSIONS

The e-NARA index is a reliable tool to assess the probability of malignant transformation of endometrioma.

Long-term risk of uterine malignancies in women with uterine fibroids confirmed by myomectomy: a population-based study

Leiomyosarcomas may originate from pre-existing uterine fibroids. However, recent studies showed that leiomyosarcomas do not arise from malignant changes in fibroids. Epidemiological data on the long-term risk of uterine malignancy with uterine fibroids are lacking. We aimed to determine whether uterine fibroids are a risk factor for uterine cancer. Patient data (2007-2020) from the Korean Health Insurance program were obtained. Using the procedure and diagnostic codes, data from patients who underwent myomectomy and appendicitis (control group) were extracted Using 1:1 propensity-score matching, 84,507 women were each allocated to the uterine fibroids and control groups. Endometrial cancer occurred in 36 44 and 44 36 women in the uterine fibroids and control groups (p = .371), respectively; 6/36 46 and 4 5/44 37 cases of uterine corpus cancer sarcoma occurred in the respective groups. Total uterine cancer (excluding cervical cancer) occurred in 46 and 39 37patients in the uterine fibroids and control groups, respectively (p = .323). A higher risk of uterine malignancy was not found in women with uterine fibroids confirmed by myomectomy. If surgery is indicated, a myomectomy can be safely performed without increasing the cancer risk. IMPACT STATEMENTWhat is already known on this subject? Traditionally, leiomyosarcomas were considered to originate from pre-existing uterine fibroids. However, recent studies suggest that leiomyosarcomas do not arise from the malignant change of fibroids. Meanwhile, there is a dearth of real-world evidence on the risk of uterine cancer in patients with uterine fibroids.What do the results of this study add? No evidence of a higher risk of uterine malignancy was found in women having uterine fibroids confirmed by myomectomy in this population-based study. In our cohort of women with uterine fibroids, tissue injury by myomectomy does not appear to cause malignant transformation.What are the implications of these findings for clinical practice and/or further research? Uterine fibroids doesn't appear to be a risk factor for uterine malignancies, and tissue injury by myomectomy does not appear to cause malignant transformation. If surgery is indicated, myomectomy can be performed safely, given that the long-term risk of uterine malignancy does not increase.

A multi-level investigation of the genetic relationship between endometriosis and ovarian cancer histotypes

Endometriosis is associated with increased risk of epithelial ovarian cancers (EOCs). Using data from large endometriosis and EOC genome-wide association meta-analyses, we estimate the genetic correlation and evaluate the causal relationship between genetic liability to endometriosis and EOC histotypes, and identify shared susceptibility loci. We estimate a significant genetic correlation (r_g) between endometriosis and clear cell (r_g = 0.71), endometrioid (r_g = 0.48), and high-grade serous (r_g = 0.19) ovarian cancer, associations supported by Mendelian randomization analyses. Bivariate meta-analysis identified 28 loci associated with both endometriosis and EOC, including 19 with evidence for a shared underlying association signal. Differences in the shared risk suggest different underlying pathways may contribute to the relationship between endometriosis and the different histotypes. Functional annotation using transcriptomic and epigenomic profiles of relevant tissues/cells highlights several target genes. This comprehensive analysis reveals profound genetic overlap between endometriosis and EOC histotypes with valuable genomic targets for understanding the biological mechanisms linking the diseases.

•

Endometriosis is genetically correlated with CCOC, ENOC, and HGSOC

•

Genetic liability to endometriosis confers risk of these EOC histotypes

•

Profound colocalization of genetic associations at endometriosis and EOC risk loci

•

Functional annotation highlights shared target genes elucidating the genetic link

Endometriosis and gynaecological cancers: molecular insights behind a complex machinery

Endometriosis is described as the presence of both endometrial glandular and stromal cells outside the uterine cavity. A major characterization of this disease is ectopic implantation of endometrial cells with increased migration. It is one of the leading causes of morbidity among premenopausal women, with a prevalence of 10-16% of women of reproductive age. Despite over century of intensive research, none of the current treatment options represents a real cure. Based on the current knowledge, endometriosis, particularly its atypical version, is considered to be a transitional form from benign disease to tumour. However, the exact mechanisms of this conversion are still not fully established.

Screening differentially expressed genes between endometriosis and ovarian cancer to find new biomarkers for endometriosis

AIM

Endometriosis is one of the most common reproductive system diseases, but the mechanisms of disease progression are still unclear. Due to its high recurrence rate, searching for potential therapeutic biomarkers involved in the pathogenesis of endometriosis is an urgent issue.

METHODS

Due to the similarities between endometriosis and ovarian cancer, four endometriosis datasets and one ovarian cancer dataset were downloaded from Gene Expression Omnibus (GEO) database. Differentially expressed genes (DEGs) were identified, followed by gene ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway and protein-protein interaction (PPI) analyses. Then, we validated gene expression and performed survival analysis with ovarian serous cystadenocarcinoma (OV) datasets in TCGA/GTEx database, and searched for potential drugs in the Drug-Gene Interaction Database. Finally, we explored the miRNAs of key genes to find biomarkers associated with the recurrence of endometriosis.

RESULTS

In total, 104 DEGs were identified in the endometriosis datasets, and the main enriched GO functions included cell adhesion, extracellular exosome and actin binding. Fifty DEGs were identified between endometriosis and ovarian cancer datasets including 11 consistently regulated genes, and nine DEGs with significant expression in TCGA/GTEx. Only IGHM had both significant expression and an association with survival, three module DEGs and two significantly expressed DEGs had drug associations, and 10 DEGs had druggability.

CONCLUSIONS

ITGA7, ITGBL1 and SORBS1 may help us understand the invasive nature of endometriosis, and IGHM might be related to recurrence; moreover, these genes all may be potential therapeutic targets.KEY MESSAGEThis manuscript used a bioinformatics approach to find target genes for the treatment of endometriosis.This manuscript used a new approach to find target genes by drawing on common characteristics between ovarian cancer and endometriosis.We screened relevant therapeutic agents for target genes in the drug database, and performed histological validation of target genes with both expression and survival analysis difference in cancer databases.

HE4 might be a more useful tumor biomarker to detect malignancy in patients with ovarian endometrioma when malignancy is suspected

Objective

To analyze the utility of carbohydrate antigen (CA)125 and human epididymis protein 4 (HE4) to detect malignancy in women with ovarian endometriosis, when ovarian cancer is suspected and ultrasonography results are inconclusive.

Methods

Women who underwent surgery between 2015 and 2019 for ovarian endometriosis or for adnexal masses, with a final diagnosis of ovarian carcinoma (clear cell and endometrioid) were included in this retrospective study. The women were divided into three groups: ovarian endometriosis (OE), ovarian carcinoma without endometriosis (OC), and ovarian carcinoma with endometriosis (OC + E). Adnexal masses were assessed preoperatively by transvaginal ultrasonography according to the International Ovarian Tumor Analysis (IOTA) simple rules, and CA125 and HE4 blood levels were obtained.

Results

Of 208 women, 45 had malignancy, 16 in the OC + E group and 29 in the OC group. According to transvaginal ultrasonography, 13 were classified as undetermined risk of malignancy: OC group: 3, OE group: 3, and OC + E group: 7. When we compared the tumor biomarkers, significant differences in HE4 but not in CA125 levels were found between the groups.

Conclusions

When ovarian malignancy is suspected in patients with ovarian endometriosis, HE4 is a more useful tumor biomarker to diagnose OC when ultrasonography results are inconclusive.

Diagnostic potential of differentially regulated microRNAs among endometriosis, endometrioid ovarian cancer, and endometrial cancer

Background

There is an increased risk of developing endometrioid ovarian and endometrial cancer in patients with endometriosis and there are no definitive diagnostic biomarkers available for these three associated diseases. Therefore, we evaluated the diagnostic potential of differentially expressed microRNAs (miRNAs) from the tissue samples of endometriosis, endometrioid ovarian cancer, and endometrial cancer to establish them as biomarkers for these diseases.

Materials and Methods

Ten samples of each, i.e., endometriosis, endometrioid ovarian cancer, endometrial cancer and control healthy endometrium were enrolled after obtaining ethical clearance. Differential expression of miR-16, miR-20a, miR-99b, miR-125a, miR-143, and miR-145 and some of their target genes, i.e., vascular endothelial growth factor (VEGF), hypoxia inducible factor 1A (HIF1A), cyclooxygenase 2 (COX2), and tumor necrosis factor (TNF) were quantified using quantitative reverse transcription polymerase chain reaction. Receiver operating characteristic (ROC) curve analysis was performed to predict the diagnostic potential.

Results

miR-16 and miR-20a were significantly downregulated, whereas miR-99b, miR-125a, and miR-143 were significantly upregulated in all three diseased samples. miR-145 was significantly upregulated in endometriosis and endometrioid ovarian cancer but significantly downregulated in endometrial cancer. mRNA levels of VEGF, HIF1A, COX2, and TNF were significantly increased in all three diseased samples as compared to control samples. ROC curve analysis revealed that for endometriosis, miR-99b, and miR-125a were giving highest area under curve (AUC) (0.950 and 0.733, respectively), for endometrioid carcinoma of ovary miR-143 was giving highest AUC (0.933) and for endometrioid endometrial cancer miR-16 (AUC = 0.815), miR-99b (AUC = 0.920), and miR-145 (AUC = 0.985) were found to be best predictors.

Conclusion

These findings suggest that these miRNAs can act as good predictors and discriminators of these three diseases and might serve as potential biomarkers for them.

Endometriosis-associated ovarian carcinomas: insights into pathogenesis, diagnostics, and therapeutic targets-a narrative review

Endometriosis is a benign gynecologic condition affecting up to one woman out of ten of reproductive age. It is defined by the presence of endometrial-like tissue in localizations outside of the uterine cavity. It often causes symptoms such as chronic pain, most frequently associated with the menstrual cycle, and infertility, but may also be oligo- or asymptomatic. There is evidence that some ovarian carcinoma (OC) histotypes, mainly the ovarian clear cell (OCCC) and endometrioid (EnOC) carcinoma, may arise from endometriosis. The most frequent genomic alterations in these carcinomas are mutations in the AT-rich interacting domain containing protein 1A (ARID1A) gene, a subunit of the SWI/SNF chromatin remodeling complex, and alterations in the phosphatidylinositol 3-kinase (PI3K)/AKT/mTOR pathway, which frequently co-occur. In ARID1A deficient cancers preclinical experimental data suggest different targetable mechanisms including epigenetic regulation, cell cycle, genomic instability, the PI3K/AKT/mTOR pathway, inflammatory pathways, immune modulation, or metabolic alterations as potential precision oncology approaches. Most of these strategies are relying on the concept of synthetic lethality in which tumors deficient in ARID1A are more sensitive to the different compounds. Some of these approaches are currently being or have recently been investigated in early clinical trials. The remarkably frequent occurrence of these mutations in endometriosis-associated ovarian cancer, the occurrence in a relatively young population, and the high proportion of platinum-resistant disease certainly warrants further investigation of precision oncology opportunities in this population. Furthermore, advanced knowledge about oncogenic mutations involved in endometriosis-associated ovarian carcinomas may be potentially useful for early cancer detection. However, this approach may be complicated by the frequent occurrence of somatic mutations in benign endometriotic tissue as recent studies suggest. In this narrative review of the current literature, we will discuss the data available on endometriosis-associated ovarian carcinoma, with special emphasis on epidemiology, diagnosis and molecular changes that could have therapeutic implications and clinical applicability in the future.

Endometriosis and cancer: a systematic review and meta-analysis

BACKGROUND

Endometriosis is an often chronic, inflammatory gynaecologic condition affecting 190 million women worldwide. Studies have reported an elevated cancer risk among patients with endometriosis. However, prior research has included methodologic issues that impede valid and robust interpretation.

OBJECTIVE AND RATIONALE

We conducted a meta-analysis of studies investigating the association between endometriosis and cancer risk and analysed the results by methodologic characteristics. We discuss the implications of cancer screening in patients and management challenges faced by clinicians.

SEARCH METHODS

We searched PubMed and Embase databases for eligible studies from inception through 24 October 2019. We included cohort and case-control studies examining the association between endometriosis and cancer risk; cross-sectional studies and case reports were excluded. Publications had to present risk/rate/odds estimates with 95% CI. Random effects meta-analysis was used to estimate summary relative risks (SRR) and CIs. Heterogeneity across studies was assessed by the Q test and I2 statistics, and publication bias using Egger's and Begg's tests. Risk of bias and quality of the included studies were assessed using the risk of bias in non-randomized studies of interventions (ROBINS-I) tool.

OUTCOMES

Forty-nine population-based case-control and cohort studies were included. Twenty-six studies were scored as having a 'serious'/'critical' risk of bias, and the remaining 23 'low'/'moderate'. Cancer-specific analyses showed a positive association between endometriosis and ovarian cancer risk (SRR = 1.93, 95% CI = 1.68-2.22; n = 24 studies) that was strongest for clear cell (SRR = 3.44, 95% CI = 2.82-4.42; n = 5 studies) and endometrioid (SRR = 2.33, 95% CI = 1.82-2.98; n = 5 studies) histotypes (Pheterogeneity < 0.0001), although with significant evidence of both heterogeneity across studies and publication bias (Egger's and Begg's P-values < 0.01). A robust association was observed between endometriosis and thyroid cancer (SRR = 1.39, 95% CI =1.24-1.57; n = 5 studies), a very small association with breast cancer (SRR = 1.04, 95% CI =1.00-1.09; n = 20 studies) and no association with colorectal cancer (SRR = 1.00, 95% CI =0.87-1.16; n = 5 studies). The association with endometrial cancer was not statistically significant (SRR = 1.23, 95% CI =0.97-1.57; n = 17 studies) overall and wholly null when restricted to prospective cohort studies (SRR = 0.99, 95% CI =0.72-1.37; n = 5 studies). The association with cutaneous melanoma was also non-significant (SRR = 1.17, 95% CI =0.97-1.41; n = 7 studies) but increased in magnitude and was statistically significant when restricted to studies with low/moderate risk of bias (SRR = 1.71, 95% CI = 1.24-2.36, n = 2 studies). The most robust finding both in terms of statistical significance and magnitude of effect was an inverse association with cervical cancer (SRR = 0.68, 95% CI =0.56-0.82; n = 4 studies); however, this result has a high potential to reflect heightened access to detection of dysplasia for women who reached an endometriosis diagnosis and is thus likely not causal. Several additional cancer types were explored based on <4 studies.

WIDER IMPLICATIONS

Endometriosis was associated with a higher risk of ovarian and thyroid, and minimally (only 4% greater risk) with breast cancer, and with a lower risk of cervical cancer. However, this meta-analysis confirms that: a majority of studies had severe/critical risk of bias; there is impactful heterogeneity across studies-and for ovarian cancer, publication bias; and causal inference requires temporality, which in many studies was not considered. We discuss the implications of these potential associations from the perspectives of patients with endometriosis, clinicians involved in their care, and scientists investigating their long-term health risks.

Endometriosis-Associated Ovarian Cancer: The Origin and Targeted Therapy

Endometrial cysts (ECs) are thought to be the origin of endometriosis-associated ovarian cancer (EAOC). A hypothesis that the oxidative stress of iron in cysts causes “malignant transformation of ECs” has been proposed, but this has not been verified. Several population-based studies showed that endometriosis was a risk factor but did not reflect the “malignant transformation of ECs”. A review showed that most patients were diagnosed with EAOC early in monitoring following detection of ECs, and that these cases might have been cancer from the start. Epidemiologically, EAOC was reduced by hysterectomy rather than by cystectomy of ECs. Gene mutation analyses identified oncogenic mutations in endometriosis and normal endometrium and revealed that the same mutations were present at different endometriotic lesions. It was also shown that most of the gene mutations found in endometriosis occurred in normal endometrium. Taking together, EAOC might be caused by eutopic endometrial glandular epithelial cells with oncogenic mutations that have undergone menstrual blood reflux and engrafted in the ovary, rather than by low-risk ECs acquiring oncogenic mutations and becoming malignant. This review discusses the mechanisms of EAOC development and targeted therapy based on genetic variation in EAOC with a focus on eutopic endometrium.

Prior uterine myoma and risk of ovarian cancer: a population-based case-control study

Objective

Uterine myoma which results in the magnitude of ovarian cancer remains uncertain. This study aimed to assess the association between women with previous uterine myoma and the risk of ovarian cancer.

Methods

This population-based case-control study was conducted using the Taiwan National Health Insurance Research Database between 2006 and 2010. We identified 4,088 adult women with newly diagnosed ovarian cancer with 16,348 women without ovarian cancer matched for age, urbanization level, income and initial diagnosis date. Logistic regression analyses were used to evaluate the variables associated with ovarian cancer. In addition, the effect of surgical interventions on the risk of ovarian cancer was also evaluated.

Results

Women with previous uterine myoma were more likely than those who did not to have ovarian cancer (adjusted odds ratio [aOR]=2.26; 95% confidence interval [CI]=2.06−2.49). Patients with uterine myoma who either received (aOR=1.79; 95% CI=1.51−2.13) or did not receive hormone replacement therapy (aOR=2.51; 95% CI=2.24−2.82) experienced a significantly higher risk of ovarian cancer than those without uterine myoma, respectively. However, patients with uterine myoma who underwent either myomectomy (aOR=0.55; 95% CI=0.39−0.77) or hysterectomy (aOR=0.33; 95% CI=0.26−0.42) had a significantly lower risk of ovarian cancer.

Conclusion

The results revealed that a significantly higher risk of ovarian cancer in women with previous uterine myoma, through an indirect mechanism. Furthermore, a lower risk of ovarian cancer was observed in women who underwent surgical removal of the uterine myoma.

Translational genomics of ovarian clear cell carcinoma

Ovarian clear cell carcinomas (OCCC) are rare aggressive, chemo-resistant tumours comprising approximately 13% of all epithelial ovarian cancers, which have distinct clinical and molecular features, when compared to other gynaecological malignancies. At present, there are no specific licensed targeted therapies for OCCC, although a number of candidate targets have been identified. This review focuses on recent knowledge underpinning our understanding of the pathogenesis of OCCC including direct and synthetic-lethal therapeutic strategies in particular focussing on ARID1A deficiency. We also discuss current targeted clinical trials and immunotherapeutic approaches.

Birth weight, childhood body mass index and height and risks of endometriosis and adenomyosis

Background: Body size in adult life is likely associated with risks of endometriosis and adenomyosis, yet little is known about associations with body size earlier in life.Aim: To examine whether birth weight, childhood body mass index (BMI) and height are associated with risks of endometriosis and adenomyosis.Subjects and methods: From the Copenhagen School Health Records Register, 171,447 girls born 1930-1996, with measured weights and heights at ages 7-13 were included. Outcomes were obtained from health registers. Cox regressions were performed to estimate hazard ratios (HR) and 95% confidence intervals (CI).Results: During follow-up, 2149 endometriosis cases and 1410 adenomyosis cases were diagnosed. Childhood BMI was inversely associated with endometriosis (HR = 0.92 [95% CI: 0.88-0.96] per z-score at age 7). In contrast, childhood height was positively associated with endometriosis (HR = 1.09 [95% CI: 1.05-1.14] per z-score at age 7). Associations with childhood body size did not differ by endometriosis location. Childhood BMI and height had limited associations with adenomyosis. Birth weight was not associated with endometriosis or adenomyosis.Conclusion: Lean and tall girls are more often diagnosed with endometriosis, but not adenomyosis. These findings suggest that indicators of endometriosis risk are already apparent at early ages.

Association of benign gynaecological diseases and risk of endometrial and ovarian cancers

Objective: Gynaecologic benign diseases such uterine fibroids share similar pathogeneses with endometrial and ovarian cancers. Whether a history of uterine fibroids increases the risk of developing endometrial or ovarian cancers is controversial, due to uterine fibroids was self-reported in those studies. Methods: In our current case-control study, 268 women with endometrial cancer and 108 women with ovarian cancer were included. In addition, 500 women without gynaecological cancers were randomly selected as a control group. Uterine fibroids in both groups were clinically diagnosed by pelvic examination and ultrasound. Data on age, parity, gravida, stages of cancers and history of uterine fibroids, endometriosis and adenomyosis were collected from hospital database. Results: After adjusted age and parity, the odds of women with history of uterine fibroids or endometriosis were lower in women with endometrial cancer than controls (odds ratio: 0.148, 95% CI: 0.097, 0.225, or 0.360, 95% CI: 0094, 1.381, respectively). The odds of women with a history of uterine fibroids or endometriosis were lower in women with ovarian cancer than controls (odds ratio: 0.141, 95% CI: 0.085, 0.235, or 1.057, 95% CI: 0.377, 2.963, respectively). However, the odds of women with a history of adenomyosis were higher in women with endometrial or ovarian cancers than controls (odd ratio: 3.757, 95% CI: 1.858, 7.599 or 2.341, 95% CI: 1.086, 5.045, respectively). Conclusion: Our observational data suggested that uterine fibroids or endometriosis may be not associated with the increased risk of developing endometrial or ovarian cancer. However, a history of adenomyosis may do.

Co-existence of leiomyomas, adenomyosis and endometriosis in women with endometrial cancer

Leiomyomas, adenomyosis, and endometriosis are reported to be risk factors for endometrial carcinoma (EC), and adenomyosis and endometriosis also for ovarian carcinoma (OC). We aimed to describe the prevalence of these conditions in EC patients with or without an OC diagnosis, and to investigate their relationship with EC risk and prognostic factors in these patients. We evaluated the co-existence of these three conditions in 1399 EC patients, and compared the prevalence of epidemiological risk factors and tumor prognostic features in patients with each condition versus not. Prevalence of conditions was also assessed in the subset of patients with prior/concurrent OC. The observed coexistence of leiomyomas, adenomyosis and endometriosis significantly deviated from that expected (P = 1.2 × 10-8). Patients were more likely to: report a younger age at menarche (PTrend = 0.004) if they had leiomyomas; have used oral contraceptives (P = 6.6 × 10-5) or had ≥2 full-term pregnancies (PTrend = 2.0 × 10-9) if they had adenomyosis; be diagnosed with EC at younger age (P = 5.0 × 10-11) if they had endometriosis. Patients with prior/concurrent OC were more likely to be diagnosed at younger age (P = 5.0 × 10-5), have endometriosis (P = 9.9 × 10-7), and present with higher stage EC (PTrend = 6.6 × 10-5). These findings justify further consideration of these gynecologic conditions as independent risk and prognostic factors for EC.

Disseminated Endometriosis and Low-Grade Endometrioid Stromal Sarcoma in a Patient with a History of Uterine Morcellation for Adenomyosis

Morcellation of benign uterine tumors allows for removal of the tumors via minimally invasive laparoscopic procedures. However, in rare cases, morcellation has been associated with upstaging of unexpected malignancies. Morcellation has also been associated with dissemination of benign pathologic processes such as endometriosis and leiomyomas. Endometrial stromal sarcoma typically arises in the uterine cavity, although cases of extrauterine endometrioid stromal sarcoma arising out of foci of endometriosis have been reported. Dissemination of endometrial stromal sarcomas can be an unintended consequence of morcellation procedures, as can dissemination of endometriosis, from which endometrioid stromal sarcomas can arise. Herein, we report a case of a 55-year-old woman who was found to have disseminated endometriosis and low-grade endometrioid stromal sarcoma, with bowel and liver parenchymal metastasis, 7 years after undergoing supracervical hysterectomy with unconfined uterine morcellation for adenomyosis. Our case highlights the potential for malignant transformation of disseminated adenomyosis/endometriosis and the importance of patient counseling and shared decision-making prior to morcellation procedures.

Endometriosis-associated Ovarian Cancer is a Subset With a More Favorable Outcome and Distinct Clinical-pathologic Characteristics

There is a controversy about whether endometriosis-associated ovarian cancer (EAOC) might represent a different entity from the corresponding ovarian cancer occurring de novo, in the absence of endometriosis. This study investigated the clinical-pathologic characteristics and outcome of EAOC compared with other ovarian carcinomas that are not associated with endometriosis (non-EAOC) in a large cohort. Seven hundred two patients meeting the inclusion criteria were further subclassified as group I when patients had ovarian carcinoma associated with or arising within endometriosis (EAOC) and group II when patients had non-EAOC. Age, gross features, histologic type, International Federation of Gynecology and Obstetrics stage, and disease-free survival (DFS) were compared between the groups. One hundred sixty-eight (23.9%) patients had EAOC, whereas 534 (76.1%) patients had non-EAOC. EAOCs were mostly endometrioid and clear cell type. Patients with EAOC were younger, present early, and had a lower rate of recurrence when compared with patients with non-EAOC, P<0.001. Patients with EAOC had longer DFS time, 51.9 mo (95% confidence interval, 44.9-58.8) versus 30.5 mo (95% confidence interval, 27.7-33.3) in non-EAOC patients. The 5 yr Kaplan-Meier estimate of DFS rate was 70% in 166 patients of group I and was 39.3% in 532 patients of group II, P<0.001. On multivariate analysis, International Federation of Gynecology and Obstetrics staging, histologic type, and treatment were the only significant factors affecting the hazards of recurrence. Patients with tumors associated with endometriosis are usually, younger, present early, have lower rate of recurrence, longer DFS, and their tumors are of lower grade and are more likely endometrioid or clear cell carcinoma.

How can we manage patients over forty with endometriosis?

Peri/postmenopausal endometriosis is not as rare as once we thought. Accumulated data revealed that around 1/3-1/4 of women with surgically-diagnosed endometriosis after the age of 40. The uneasiness of the issue of malignant transformation or malignancy in such women created a challenge for us. Here the management strategy for women with endometriosis after the age of 40 is discussed in the light of scientific evidence.

Hepatocyte nuclear factor-1 beta protects endometriotic cells against apoptotic cell death by up-regulating the expression of antiapoptotic genes†

The overexpression of hepatocyte nuclear factor-1 beta (HNF1β) in endometriotic lesion has been demonstrated. However, the role of HNF1β in endometriosis remains largely unknown. Human endometriotic 12Z cells showed higher level of HNF1β when compared with normal endometrial HES cells. In human endometriotic 12Z cells, HNF1β knockdown increased susceptibility to apoptotic cell death by oxidative stress, while HNF1β overexpression suppressed apoptosis. In addition, HNF1β knockdown and overexpression significantly decreased and increased, respectively, the expression of nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB)-dependent antiapoptotic genes. Knockdown of the antiapoptotic genes significantly reduced the HNF1β-induced resistance against oxidative stress in 12Z cells. Furthermore, HNF1β regulated the transcriptional activity of NF-κB, and an NF-κB inhibitor suppressed the HNF1β-enhanced NF-κB-dependent antiapoptotic gene expression and the resistance of the 12Z cells against cell death. Taken together, these data suggest that HNF1β overexpression may protect endometriotic cells against oxidative damage by augmenting antiapoptotic gene expression.

The Association Between Hysterectomy and Ovarian Cancer Risk: A Population-Based Record-Linkage Study

BACKGROUND

Recent studies have called into question the long-held belief that hysterectomy without oophorectomy protects against ovarian cancer. This population-based longitudinal record-linkage study aimed to explore this relationship, overall and by age at hysterectomy, time period, surgery type, and indication for hysterectomy.

METHODS

We followed the female adult Western Australian population (837 942 women) across a 27-year period using linked electoral, hospital, births, deaths, and cancer records. Surgery dates were determined from hospital records, and ovarian cancer diagnoses (n = 1640) were ascertained from cancer registry records. We used Cox regression to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for the association between hysterectomy and ovarian cancer incidence.

RESULTS

Hysterectomy without oophorectomy (n = 78 594) was not associated with risk of invasive ovarian cancer overall (HR = 0.98, 95% CI = 0.85 to 1.11) or with the most common serous subtype (HR = 1.05, 95% CI = 0.89 to 1.23). Estimates did not vary statistically significantly by age at procedure, time period, or surgical approach. However, among women with endometriosis (5.8%) or with fibroids (5.7%), hysterectomy was associated with substantially decreased ovarian cancer risk overall (HR = 0.17, 95% CI = 0.12 to 0.24, and HR = 0.27, 95% CI = 0.20 to 0.36, respectively) and across all subtypes.

CONCLUSIONS

Our results suggest that for most women, having a hysterectomy with ovarian conservation is not likely to substantially alter their risk of developing ovarian cancer. However, our results, if confirmed, suggest that ovarian cancer risk reduction could be considered as a possible benefit of hysterectomy when making decisions about surgical management of endometriosis or fibroids.

Metabolomic profile as a noninvasive adjunct tool for the diagnosis of Grades III and IV endometriosis-related infertility

The aim of the present case-control study was to develop a noninvasive adjuvant tool for the diagnosis of endometriosis. Serum samples from 100 patients undergoing intracytoplasmic sperm injection were split into two groups according to the cause of infertility: an endometriosis group (n = 50), consisting of samples derived from patients with Grade III and IV endometriosis, and a control group (n = 50), comprising samples derived from patients with isolated male factor infertility. The metabolomic profile of each sample was obtained, through mass spectrometry. Partial least squares discriminant analysis was able to clearly classify the endometriosis and control groups. Ten potential biomarkers were selected based on their importance for model prediction. These ions were used to build the receiver-operating characteristic curve, which presented an area under the curve of 0.904 (95% confidence interval: 0.796-0.985). To validate the model, 30 other samples from infertile women without any evidence of endometriosis were tested. Considering these ions as possible biomarkers, the model was able to correctly classify 84% of the patients. Finally, a similar prediction potential was observed in the model validated set, when samples from the disease-free group were tested. Serum metabolomics may be useful as a noninvasive adjunct tool for the selection of patients who must undergo laparoscopy for definitive endometriosis diagnosis.

Epithelial ovarian cancer risk: A review of the current genetic landscape

Ovarian cancer is the fourth most common cause of cancer-related death in women in the developed world, and one of the most heritable cancers. One of the most significant risk factors for epithelial ovarian cancer (EOC) is a family history of breast and/or ovarian cancer. Combined risk factors can be used in models to stratify risk of EOC, and aid in decisions regarding risk-reduction strategies. Germline pathogenic variants in EOC susceptibility genes including those involved in homologous recombination and mismatch repair pathways are present in approximately 22% to 25% of EOC. These genes are associated with an estimated lifetime risk of EOC of 13% to 60% for BRCA1 variants and 10% to 25% for BRCA2 variants, with lower risks associated with remaining genes. Genome-wide association studies have identified single nucleotide polymorphisms (SNPs) thought to explain an additional 6.4% of the familial risk of ovarian cancer, with 34 susceptibility loci identified to date. However, an unknown proportion of the genetic component of EOC risk remains unexplained. This review comprises an overview of individual genes and SNPs suspected to contribute to risk of EOC, and discusses use of a polygenic risk score to predict individual cancer risk more accurately.

Incidence of second primary malignancy after breast cancer and related risk factors-Is breast-conserving surgery safe? A nested case-control study

Risk of second primary malignancy (SPM) is increasing. We aimed to assess the incidence and related risk factors of SPM among breast cancer (BC) patients from this nested case-control study using the SEER database. BC patients with SPM were identified as the case group and SPM-free patients were defined as the control group. Propensity score matching of cases with controls by the year of the first primary BC diagnosis was conducted at the ratio of 1:5, and 97,242 BC patients were enrolled from 1998 to 2013 after the matching. The incidence of SPM in BC patients stratified by age groups and cancer sites was compared to the general population using the adjusted standardized incidence ratio (SIR) and the risk factors for SPM were examined using Cox proportional hazard regressions. Our study showed BC patients had excess risk for SPM than the general population (adjusted SIR for all cancer sites = 12.94, p < 0.001) and the incidence of SPM among them decreased with age. The risk of SPM was significantly related to the following demographical and clinical variables: age (40-59 vs. 18-39, HR = 1.33; 60-79 vs. 18-39, HR = 2.39; ≥80 vs. 18-39, HR = 2.84), race (black vs. white, HR = 1.12), histological type (lobular BC vs. ductal BC, HR = 1.15), radiotherapy (HR = 1.33), marital status (married vs. single, HR = 0.88) and estrogen receptor status (positive vs. negative, HR = 0.85). Consistent results were found in subgroup analysis stratified by contralateral-breast SPMs and nonbreast SPMs.

Endometriosis-associated ovarian cancer: What have we learned so far?

Endometriosis is defined as the presence of ectopic endometrial tissue outside of the uterine cavity, most commonly in the ovaries and peritoneum. It is a complex disease that is influenced by multiple factors. It is also a common gynecological disorder and affects approximately 10-15% of all women of reproductive age. Recent molecular and pathological studies indicate that endometriosis may serve as a precursor of ovarian cancer (endometriosis-associated ovarian cancer, EAOC), particularly endometrioid and clear cell ovarian cancers. Although histological and epidemiological studies have demonstrated that endometriosis has a malignant potential, the molecular mechanism that underlies the malignant transformation of endometriosis is still controversial, and the precise mechanism of carcinogenesis must be fully elucidated. Currently, the development and improvement of a new sequencing technology, next-generation sequencing (NGS), has been increasingly relevant in cancer genomics research. Recently, NGS has also been utilized in clinical oncology to advance the personalized treatment of cancer. In addition, the sensitivity, speed, and cost make NGS a highly attractive platform compared to other sequencing modalities. For this reason, NGS may lead to the identification of driver mutations and underlying pathways associated with EAOC. Here, we present an overview of the molecular pathways that have led to the current opinions on the relationship between endometriosis and ovarian cancer.

Impact of endometriosis on risk of ovarian, endometrial and cervical cancers: a meta-analysis

PURPOSE

The risks of gynecologic cancer have not been well established in women with endometriosis. The objective of the present study was to investigate the influence of endometriosis on the risk for three gynecologic cancer (ovarian cancer, endometrial cancer and cervical cancer).

METHODS

We gathered updated evidence about the risk relationship between endometriosis and gynecologic cancers by conducting a comprehensive search of several medical literature electronic databases, including PubMed, Embase and the Cochrane Library. The design and quality of all studies were evaluated using the Newcastle-Ottawa Scale (NOS), and a random-effects model was used to calculate pooled risk ratio (RR).

RESULTS

Of the 8538 articles our search produced, we selected 25 qualified studies, including 16 cohort studies and 9 case-control studies. Patients with endometriosis had both an increased risk of ovarian cancer [RR  1.964; 95% CI (1.685, 2.290)]. The risk of endometrial cancer (EC) is not necessarily higher in patients with endometriosis [RR 1.176, 95% CI (0.878, 1.575)]. Endometriosis was not associated with an increased risk for cervical cancer (CC) [RR 0.670, 95% CI (0.537, 0.838)].

CONCLUSIONS

Patients with endometriosis need to be closely observed and rechecked regularly to prevent malignant changes.

Modern approaches to noninvasive diagnosis of malignant transformation of endometriosis

Endometriosis-associated ovarian cancer (EAOC) is a rare entity and has highly variable morphological presentations. Mural nodules can be seen in EAOC and benign ovarian endometrioma (OE), which causes a diagnostic dilemma. The differential diagnosis between early-stage EAOC with predominantly cystic appearances and benign OE remains a challenge for physicians. This study will summarize recent knowledge of diagnosis of malignant transformation of endometriosis that have been studied through an innovative approach based on a wide array of novel technologies. Using PubMed database, we focused on the biochemical and technical advancement in the differential diagnosis of benign and malignant endometriosis. Compared with the subjects with benign OE, cyst fluid hemoglobin and iron-related compounds levels were significantly lower in patients with EAOC. This observation opens up the possibility of early diagnosis before morphological variations are captured through ultrasonographic and magnetic resonance (MR) imaging diagnosis. The metallobiology technology offers one solution to this challenge. We discuss the noninvasive diagnosis of EAOC via various imaging methods, including electronic absorption spectroscopy, near infrared approach and MR transverse relaxometry. Special emphasis is given to recent advances in the noninvasive imaging modalities.

Clotrimazole is effective for the regression of endometriotic implants in a Wistar rat experimental model of endometriosis

The present work aimed to evaluate molecular, angiogenic and inflammatory changes induced by clotrimazole (CTZ) on endometriosis lesions. For this, thirty female Wistar rats with surgically implanted autologous endometrium were treated with CTZ or vehicle (200 mg/kg) via esophageal gavage for 15 consecutive days. CTZ treatment significantly decreased the growth and the size of the implants, and histological examination indicated regression and atrophy, with no toxicity to the animals. The levels of the angiogenic markers VEGF and VEGFR-2 were significantly decreased in CTZ group. The treatment also promotes a reduction on PGE₂ and TNF-α levels. All these effects involve the amelioration of ERK1/2, Akt, AMPK and PERK signaling upon CTZ treatment. In conclusion, CTZ promoted an overall amelioration of endometriosis in a rat model due to the anti-angiogenic properties of the drug. Therefore, our results support the proposal of a clinical trial using CTZ for the treatment of endometriosis.

Benign gynecologic conditions are associated with ovarian cancer risk in African-American women: a case-control study

BACKGROUND

The association between common benign gynecologic conditions and ovarian cancer remains under-studied in African Americans. Therefore, we examine the association between self-reported history of benign gynecologic conditions and epithelial ovarian cancer risk in African-American women.

METHODS

Data from a large population-based, multi-center case-control study of epithelial ovarian cancer in African-American women were analyzed to estimate the association between self-reported history of endometriosis, pelvic inflammatory disease (PID), fibroid, and ovarian cyst with epithelial ovarian cancer. Logistic regression was used to calculate odds ratios (OR) and 95% confidence intervals (CI) for the associations between individual and composite gynecologic conditions and ovarian cancer.

RESULTS

600 cases and 752 controls enrolled in the African American Cancer Epidemiology Study between 1 December 2010 and 31 December 2015 comprised the study population. After adjusting for potential confounders, a history of endometriosis was associated with ovarian cancer (OR 1.78; 95% CI 1.09-2.90). A non-significant association of similar magnitude was observed with PID (OR 1.33; 95% CI 0.82-2.16), while no association was observed in women with a history of fibroid or ovarian cyst. A positive trend was observed for an increasing number of reported gynecologic conditions (p = 0.006) with consistency across histologic subtypes and among both oral contraceptive users and non-users.

CONCLUSION

A self-reported history of endometriosis among African-American women was associated with increased risk of ovarian cancer. Having multiple benign gynecologic conditions also increased ovarian cancer risk.

Differential expression of mTOR components in endometriosis and ovarian cancer: Effects of rapalogues and dual kinase inhibitors on mTORC1 and mTORC2 stoichiometry

Endometriosis is a well‑known risk factor for ovarian cancer. The genetic changes that characterise endometriosis are poorly understood; however, the mechanistic target of rapamycin (mTOR) pathway is involved. In this study, we investigated the expression of key mTOR components in endometriosis and the effects of rapalogues using an endometrioid ovarian carcinoma cell line (MDAH 2774) as an in vitro model. Gene expression of mTOR, DEPTOR, Rictor and Raptor was assessed by qPCR in 24 endometriosis patients and in silico in ovarian cancer patients. Furthermore, the effects of Rapamycin, Everolimus, Deforolimus, Temsirolimus, Resveratrol, and BEZ235 (Dactolisib, a dual kinase inhibitor) on mTOR signalling components was assessed. mTOR showed a significant increase in the expression in endometriosis and ovarian endometrioid adenocarcinoma patients compared to non‑affected controls. DEPTOR, an inhibitor of mTOR, was downregulated in the advanced stages of ovarian cancer (III and IV) compared to earlier stages (I and II). Treatment of MDAH‑2774 cells with the mTOR inhibitors resulted in the significant upregulation of DEPTOR mRNA, whereas treatment with rapamycin and BEZ‑235 (100 nM) resulted in downregulation of the mTOR protein expression after 48 h of treatment. None of the treatments resulted in translocation of mTOR from cytoplasm to nucleus. Upregulation of DEPTOR is a positive prognostic marker in ovarian cancer and is increased in response to mTOR pathway inhibition suggesting that it functions as a tumour suppressor gene in endometrioid ovarian carcinoma. Collectively, our data suggest the mTOR pathway as a potential connection between endometriosis and ovarian cancer and may be a potential target in the treatment of both conditions.

Genetic overlap between endometriosis and endometrial cancer: evidence from cross-disease genetic correlation and GWAS meta-analyses

Epidemiological, biological, and molecular data suggest links between endometriosis and endometrial cancer, with recent epidemiological studies providing evidence for an association between a previous diagnosis of endometriosis and risk of endometrial cancer. We used genetic data as an alternative approach to investigate shared biological etiology of these two diseases. Genetic correlation analysis of summary level statistics from genomewide association studies (GWAS) using LD Score regression revealed moderate but significant genetic correlation (rg  = 0.23, P = 9.3 × 10-3 ), and SNP effect concordance analysis provided evidence for significant SNP pleiotropy (P = 6.0 × 10-3 ) and concordance in effect direction (P = 2.0 × 10-3 ) between the two diseases. Cross-disease GWAS meta-analysis highlighted 13 distinct loci associated at P ≤ 10-5 with both endometriosis and endometrial cancer, with one locus (SNP rs2475335) located within PTPRD associated at a genomewide significant level (P = 4.9 × 10-8 , OR = 1.11, 95% CI = 1.07-1.15). PTPRD acts in the STAT3 pathway, which has been implicated in both endometriosis and endometrial cancer. This study demonstrates the value of cross-disease genetic analysis to support epidemiological observations and to identify biological pathways of relevance to multiple diseases.

The Role of Oxidative Stress and Membrane Transport Systems during Endometriosis: A Fresh Look at a Busy Corner

Endometriosis is a condition characterized by the presence of endometrial tissue outside the uterine cavity, leading to a chronic inflammatory reaction. It is one of the most widespread gynecological diseases with a 10-15% prevalence in the general female population, rising up to 30-45% in patients with infertility. Although it was first described in 1860, its etiology and pathogenesis are still unclear. It is now accepted that inflammation plays a central role in the development and progression of endometriosis. In particular, it is marked by an inflammatory process associated with the overproduction of an array of inflammatory mediators such as prostaglandins, metalloproteinases, cytokines, and chemokines. In addition, the growth and adhesion of endometrial cells in the peritoneal cavity due to reactive oxygen species (ROS) and free radicals lead to disease onset, its ensuing symptoms-among which pain and infertility. The aim of our review is to evaluate the role of oxidative stress and ROS in the pathogenesis of endometriosis and the efficacy of antioxidant therapy in the treatment and mitigation of its symptoms.

Patients with uterine leiomyoma exhibit a high incidence but low mortality rate for breast cancer

The association of uterine leiomyoma with increased risk of breast cancer is controversial. Therefore, we used the National Health Insurance Research Database of Taiwan to examine breast cancer incidence and mortality among Asian patients with and without uterine leiomyoma. We compared breast cancer incidence and mortality between 22,001 newly diagnosed uterine leiomyoma patients and 85,356 individuals without uterine leiomyoma matched by age and date of diagnosis. Adjusted hazard ratios for breast cancer were estimated using the Cox model. The incidence of breast cancer was 35% higher in the uterine leiomyoma group than the leiomyoma-free group (1.65 vs. 1.22 per 1,000 individuals, p < 0.001), with an adjusted hazard ratio of 1.31 (95% confidence interval = 1.13−1.52). Interestingly, overall mortality was lower (4.12%) in the uterine leiomyoma group (mean followed time, 3.59 ± 2.70 years) than the leiomyoma-free group (8.78%; mean followed time, 3.54 ± 2.67 years) at the endpoint of the study (p <0.05). These findings indicate the incidence of breast cancer is higher in patients with uterine leiomyoma than in those without it, but overall mortality from breast cancer was lower in the patients with uterine leiomyoma.

Endometriosis: Diagnosis and Management

Objective

To improve the understanding of endometriosis and to provide evidence-based guidelines for the diagnosis and management of endometriosis.

Outcomes

Outcomes evaluated include the impact of the medical and surgical management of endometriosis on women's experience of morbidity and infertility.

Methods

Members of the guideline committee were selected on the basis of individual expertise to represent a range of practical and academic experience in terms of both location in Canada and type of practice, as well as subspecialty expertise along with general gynaecology background. The committee reviewed all available evidence in the English and French medical literature and available data from a survey of Canadian women. Recommendations were established as consensus statements. The final document was reviewed and approved by the Executive and Council of the SOGC.

Results

This document provides a summary of up-to-date evidence regarding diagnosis, investigations, and medical and surgical management of endometriosis. The resulting recommendations may be adapted by individual health care workers when serving women with this condition.

Conclusions

Endometriosis is a common and sometimes debilitating condition for women of reproductive age. A multidisciplinary approach involving a combination of lifestyle modifications, medications, and allied health services should be used to limit the impact of this condition on activities of daily living and fertility. In some circumstances surgery is required to confirm the diagnosis and provide therapy to achieve the desired goal of pain relief or improved fecundity. Women who find an acceptable management strategy for this condition may have an improved quality of life or attain their goal of successful pregnancy.

Evidence

Medline and Cochrane databases were searched for articles in English and French on subjects related to endometriosis, pelvic pain, and infertility from January 1999 to October 2009 in order to prepare a Canadian consensus guideline on the management of endometriosis.

Values

The quality of evidence was rated with use of the criteria described by the Canadian Task Force on Preventive Health Care. Recommendations for practice were ranked according to the method described by the Task Force. See Table 1.

Benefits, harms, and costs

Implementation of the guideline recommendations will improve the care of women with pain and infertility associated with endometriosis.

Integrating the dysregulated inflammasome-based molecular functionome in the malignant transformation of endometriosis-associated ovarian carcinoma

The coexistence of endometriosis (ES) with ovarian clear cell carcinoma (CCC) or endometrioid carcinoma (EC) suggested that malignant transformation of ES leads to endometriosis associated ovarian carcinoma (EAOC). However, there is still lack of an integrating data analysis of the accumulated experimental data to provide the evidence supporting the hypothesis of EAOC transformation. Herein we used a function-based analytic model with the publicly available microarray datasets to investigate the expression profiling between ES, CCC, and EC. We analyzed the functional regularity pattern of the three type of samples and hierarchically clustered the gene sets to identify key mechanisms regulating the malignant transformation of EAOC. We identified a list of 18 genes (NLRP3, AIM2, PYCARD, NAIP, Caspase-4, Caspase-7, Caspase-8, TLR1, TLR7, TOLLIP, NFKBIA, TNF, TNFAIP3, INFGR2, P2RX7, IL-1B, IL1RL1, IL-18) closely related to inflammasome complex, indicating an important role of inflammation/immunity in EAOC transformation. We next explore the association between these target genes and patient survival using Gene Expression Omnibus (GEO), and found significant correlation between the expression levels of the target genes and the progression-free survival. Interestingly, high expression levels of AIM2 and NLRP3, initiating proteins of inflammasomes, were significantly correlated with poor progression-free survival. Immunohistochemistry staining confirmed a correlation between high AIM2 and high Ki-67 in clinical EAOC samples, supporting its role in disease progression. Collectively, we established a bioinformatic platform of gene-set integrative molecular functionome to dissect the pathogenic pathways of EAOC, and demonstrated a key role of dysregulated inflammasome in modulating the malignant transformation of EAOC.

Discovering the Deregulated Molecular Functions Involved in Malignant Transformation of Endometriosis to Endometriosis-Associated Ovarian Carcinoma Using a Data-Driven, Function-Based Analysis

The clinical characteristics of clear cell carcinoma (CCC) and endometrioid carcinoma EC) are concomitant with endometriosis (ES), which leads to the postulation of malignant transformation of ES to endometriosis-associated ovarian carcinoma (EAOC). Different deregulated functional areas were proposed accounting for the pathogenesis of EAOC transformation, and there is still a lack of a data-driven analysis with the accumulated experimental data in publicly-available databases to incorporate the deregulated functions involved in the malignant transformation of EOAC. We used the microarray gene expression datasets of ES, CCC and EC downloaded from the National Center for Biotechnology Information Gene Expression Omnibus (NCBI GEO) database. Then, we investigated the pathogenesis of EAOC by a data-driven, function-based analytic model with the quantified molecular functions defined by 1454 Gene Ontology (GO) term gene sets. This model converts the gene expression profiles to the functionome consisting of 1454 quantified GO functions, and then, the key functions involving the malignant transformation of EOAC can be extracted by a series of filters. Our results demonstrate that the deregulated oxidoreductase activity, metabolism, hormone activity, inflammatory response, innate immune response and cell-cell signaling play the key roles in the malignant transformation of EAOC. These results provide the evidence supporting the specific molecular pathways involved in the malignant transformation of EAOC.

Epidemiology of ovarian cancer: a review

Ovarian cancer (OC) is the seventh most commonly diagnosed cancer among women in the world and the tenth most common in China. Epithelial OC is the most predominant pathologic subtype, with five major histotypes that differ in origination, pathogenesis, molecular alterations, risk factors, and prognosis. Genetic susceptibility is manifested by rare inherited mutations with high to moderate penetrance. Genome-wide association studies have additionally identified 29 common susceptibility alleles for OC, including 14 subtype-specific alleles. Several reproductive and hormonal factors may lower risk, including parity, oral contraceptive use, and lactation, while others such as older age at menopause and hormone replacement therapy confer increased risks. These associations differ by histotype, especially for mucinous OC, likely reflecting differences in etiology. Endometrioid and clear cell OC share a similar, unique pattern of associations with increased risks among women with endometriosis and decreased risks associated with tubal ligation. OC risks associated with other gynecological conditions and procedures, such as hysterectomy, pelvic inflammatory disease, and polycystic ovarian syndrome, are less clear. Other possible risk factors include environmental and lifestyle factors such as asbestos and talc powder exposures, and cigarette smoking. The epidemiology provides clues on etiology, primary prevention, early detection, and possibly even therapeutic strategies.

Epidemiology of ovarian cancer: a review

Ovarian cancer (OC) is the seventh most commonly diagnosed cancer among women in the world and the tenth most common in China. Epithelial OC is the most predominant pathologic subtype, with five major histotypes that differ in origination, pathogenesis, molecular alterations, risk factors, and prognosis. Genetic susceptibility is manifested by rare inherited mutations with high to moderate penetrance. Genome-wide association studies have additionally identified 29 common susceptibility alleles for OC, including 14 subtype-specific alleles. Several reproductive and hormonal factors may lower risk, including parity, oral contraceptive use, and lactation, while others such as older age at menopause and hormone replacement therapy confer increased risks. These associations differ by histotype, especially for mucinous OC, likely reflecting differences in etiology. Endometrioid and clear cell OC share a similar, unique pattern of associations with increased risks among women with endometriosis and decreased risks associated with tubal ligation. OC risks associated with other gynecological conditions and procedures, such as hysterectomy, pelvic inflammatory disease, and polycystic ovarian syndrome, are less clear. Other possible risk factors include environmental and lifestyle factors such as asbestos and talc powder exposures, and cigarette smoking. The epidemiology provides clues on etiology, primary prevention, early detection, and possibly even therapeutic strategies.

Endometriosis and risk of ovarian and endometrial cancers in a large prospective cohort of U.S. nurses

PURPOSE

Endometriosis is associated with ovarian cancer, but the relation with endometrial cancer is unclear. Prior studies generally were retrospective and had potential limitations, including use of self-reported endometriosis, failure to account for delays between symptom onset and endometriosis diagnosis, and changes in risk factors post-endometriosis diagnosis. We evaluated whether these limitations obscured a weak association with endometrial cancer and the extent to which these limitations impacted associations with ovarian cancer.

METHODS

Cox proportional hazards regression models were used to assess associations between endometriosis and cancer risk, evaluating the impacts of self-reported vs. laparoscopically confirmed endometriosis, delayed diagnosis, and post-endometriosis diagnosis changes in risk factor exposures on relative risk estimates.

RESULTS

Over 18 years of follow-up, we identified 228 ovarian and 166 endometrial cancers among 102,025 and 97,109 eligible women, respectively. Self-reported endometriosis was associated with ovarian cancer [relative risk (RR): 1.81; 95% confidence interval (CI): 1.26-2.58]; this association was stronger for laparoscopically confirmed endometriosis (HR: 2.14; 95% CI 1.45-3.15). No association was observed with endometrial cancer (self-report RR: 0.78; 95% CI 0.42-1.44; laparoscopic-confirmation RR: 0.76; 95% CI 0.35-1.64). Accounting for diagnosis delays or post-endometriosis diagnosis changes in risk factors had a little impact.

CONCLUSIONS

This study adds to the evidence that endometriosis is not strongly linked to endometrial cancer risk and that the association with ovarian cancer is robust to misclassification, diagnostic delay, and changes in exposures post-endometriosis diagnosis. Our analysis suggests that confounding and misclassification do not obscure a weak association for endometrial cancer risk, although our results should be replicated.

Hormonal and reproductive factors and the risk of ovarian cancer

PURPOSE

Hormone-related factors have been associated with ovarian cancer, the strongest being parity and oral contraceptive use. Given reductions in birth rates and increases in oral contraceptive use over time, associations in more recent birth cohorts may differ. Furthermore, consideration of ovarian cancer heterogeneity (i.e., Type I/II invasive cancers) may contribute to a better understanding of etiology. We examined hormone-related factors in relation to ovarian cancer risk overall, for Type I and Type II cancers, as well as borderline tumors.

METHODS

A population-based case-control study was carried out in Montreal, Canada from 2011 to 2016, including 496 cases and 908 controls. For each hormone-related variable, adjusted odds ratios (OR) and 95% confidence intervals (CI) were estimated using logistic regression for ovarian cancer overall, and using polytomous logistic regression for associations by tumor behavior and ovarian cancer type.

RESULTS

Parity was inversely associated with risk overall and by tumor behavior and type, with a stronger OR (95% CI) for Type I [0.09 (0.04-0.24) for ≥3 full-term births vs. nulliparity] vs. Type II [0.66 (0.43-1.02)] invasive cancers; the OR (95% CI) for borderline tumors was 0.41 (0.22-0.77). Oral contraceptive ever use was not associated with risk overall, but ≥10 years of use vs. never use reduced risk, particularly for invasive cancers. A history of endometriosis was most strongly associated with Type I cancers. Associations with other factors were less clear.

CONCLUSIONS

These results suggest that associations with some hormone-related factors may differ between borderline and invasive Type I and II ovarian cancers.