Diagnosing endometrial hyperplasia: why is it so difficult to agree?

Concurrent endometrial cancer in atypical endometrial hyperplasia and the role of sentinel lymph nodes: clinical insights from a multicenter experience

OBJECTIVE

This study aimed to evaluate the prevalence of concurrent endometrial cancer in patients pre-operatively diagnosed with atypical endometrial hyperplasia undergoing hysterectomy. Additionally, we assessed the occurrence of high to intermediate-risk and high-risk tumors according to the ESGO-ESTRO-ESP classification. The study also compared surgical outcomes and complications between patients undergoing simple hysterectomy and those undergoing hysterectomy with sentinel lymph node biopsy.

METHODS

In this multicenter retrospective study, patients with a pre-operative diagnosis of atypical endometrial hyperplasia were identified and divided into two groups: Group 1, which included patients treated with total hysterectomy with or without bilateral salpingo-oophorectomy, and Group 2, where sentinel lymph node biopsy was incorporated into the standard surgical treatment.

RESULTS

Among 460 patients with atypical endometrial hyperplasia, 192 received standard surgical management (Group 1) and 268 underwent sentinel lymph node biopsy (Group 2). A total of 47.2% (95% CI 42.6% to 51.7%) of patients were upgraded to endometrial cancer on final histopathological examination. High to intermediate-risk and high-risk tumors constituted 12.3% and 9.2% in Group 2 and 7.4% and 3.7% in Group 1. Lymph node metastases were identified in 7.6% of patients with concurrent endometrial cancer who underwent nodal assessment with at least unilateral mapping. Of the 12 sentinel lymph node metastases, 75.0% were micrometastases, 16.7% macrometastases, and 8.3% isolated tumor cells. No significant differences were found in estimated blood loss, operative time, and intra-operative and post-operative complications between the two groups. The rate of patients undergoing sentinel lymph node biopsy doubled every 2 years (OR 2.010, p<0.001), reaching 79.1% in the last 2 years.

CONCLUSION

This study found a prevalence of concurrent endometrial cancer of 47.2%, and sentinel lymph node biopsy provided prognostic and therapeutic information in 60.8% of cases. It also allowed for the adjustment of adjuvant therapy in 12.3% of high to intermediate-risk patients without increasing operative time or complication rates.

Factors associated with interobserver variation amongst pathologists in the diagnosis of endometrial hyperplasia: A systematic review

OBJECTIVE

Reproducible diagnoses of endometrial hyperplasia (EH) remains challenging and has potential implications for patient management. This systematic review aimed to identify pathologist-specific factors associated with interobserver variation in the diagnosis and reporting of EH.

METHODS

Three electronic databases, namely MEDLINE, Embase and Web of Science, were searched from 1st January 2000 to 25th March 2023, using relevant key words and subject headings. Eligible studies reported on pathologist-specific factors or working practices influencing interobserver variation in the diagnosis of EH, using either the World Health Organisation (WHO) 2014 or 2020 classification or the endometrioid intraepithelial neoplasia (EIN) classification system. Quality assessment was undertaken using the QUADAS-2 tool, and findings were narratively synthesised.

RESULTS

Eight studies were identified. Interobserver variation was shown to be significant even amongst specialist gynaecological pathologists in most studies. Few studies investigated pathologist-specific characteristics, but pathologists were shown to have different diagnostic styles, with some more likely to under-diagnose and others likely to over-diagnose EH. Some novel working practices were identified, such as grading the "degree" of nuclear atypia and the incorporation of objective methods of diagnosis such as semi-automated quantitative image analysis/deep learning models.

CONCLUSIONS

This review highlighted the impact of pathologist-specific factors and working practices in the accurate diagnosis of EH, although few studies have been conducted. Further research is warranted in the development of more objective criteria that could improve reproducibility in EH diagnostic reporting, as well as determining the applicability of novel methods such as grading the degree of nuclear atypia in clinical settings.

Hysteroscopic biopsy compared with endometrial curettage to assess the preoperative rate of atypical hyperplasia underestimating endometrial carcinoma

PURPOSE

To evaluate the rate of atypical hyperplasia (AH) underestimating endometrial cancer (EC) comparing endometrial biopsy (EB) accomplished by hysteroscopic biopsy with dilatation and curettage (D&C). Second, to compare the two techniques to foresee EC grading.

METHODS

This trial was based on the findings of two Gynecological Departments within the same Public Utility, sharing pathological service and database but routinely performing EB under hysteroscopic visualization (group A) or hysteroscopy followed by D&C (group B). We retrieved the clinical data of patients showing EC on hysterectomy throughout a 10-year period. The accuracy of hysteroscopic-view diagnosis and EB pathology were compared, having the pathologic findings of hysterectomy as reference.

RESULTS

A total of 161 patients met the inclusion criteria. Among these, 109 and 52 were included in groups A and B, respectively. In group A, 32.1% of patients underwent EB in an out-patient setting. To foresee EC, hysteroscopic view showed a sensitivity of 82.5% and 70.2% in groups A and B, respectively (P = 0.019). An underestimation of EC diagnosed as AH on EB was found in 20 patients (12.4%). Among these, 18 (16.5%) and 2 (3.8%) were included in groups A and B, respectively (P = 0.022). In group A, a fault diagnosis of AH resulted higher when EB was performed as out-patient setting (P = 0.006). EB allowed the grading of EC in 73.3% and 90.3% of patients in groups A and B, respectively. The agreement was 73.7% and 85.1%, leading to moderate (κ = 0.56) and good (κ = 0.77) "κ" coefficient of concordance for groups A and B, respectively.

CONCLUSIONS

EB performed by D&C lowers the rate of AH underestimating concurrent EC and improves the grading agreement when compared with hysteroscopic sampling.

Utility of a PAX2, PTEN, and β-catenin Panel in the Diagnosis of Atypical Hyperplasia/Endometrioid Intraepithelial Neoplasia in Endometrial Polyps

The diagnosis of atypical hyperplasia/endometrioid intraepithelial neoplasm (AH/EIN) within endometrial polyps (EMPs) often poses a diagnostic conundrum. Our previous studies demonstrated that a panel of immunohistochemical (IHC) markers consisting of PAX2, PTEN, and β-catenin can be effectively utilized for the identification of AH/EIN. A total of 105 AH/EIN within EMP were analyzed using the 3-marker panel. We also evaluated these cases for the presence of morules. Benign EMP (n=90) and AH/EIN unassociated with polyp (n=111) served as controls. Aberrant expression of PAX2, PTEN, or β-catenin was observed in AH/EIN in EMP in 64.8%, 39.0%, and 61.9% of cases, respectively. At least 1 IHC marker was abnormal in 92.4% of cases. Overall, 60% of AH/EIN in EMP demonstrated abnormal results for≥2 IHC markers. The prevalence of PAX2 aberrancy was significantly lower in AH/EIN in EMP than in nonpolyp AH/EIN (64.8% vs. 81.1%, P =0.007), but higher than in benign EMP (64.8% vs. 14.4%, P <0.00001). The prevalence of β-catenin aberrancy was significantly higher in AH/EIN in EMP than in nonpolyp AH/EIN (61.9% vs. 47.7%, P =0.037). All control benign EMP demonstrated normal expression of PTEN and β-catenin. Morules were present in 38.1% of AH/EIN in EMP versus 24.3% in nonpolyp AH/EIN, and absent in benign EMP. A strong positive association was found between β-catenin and morules (Φ=0.64). Overall, 90% cases of atypical polypoid adenomyoma (n=6) and mucinous papillary proliferation (n=4) showed IHC marker aberrancy. In conclusion, the 3-marker IHC panel (PAX2, PTEN, and β-catenin) is (1) a useful tool in the diagnosis of AH/EIN in EMP; (2) PAX2 loss should be interpreted with caution and in combination with morphology and other markers.

β-catenin, Pax2, and Pten Panel Identifies Precancers Among Histologically Subdiagnostic Endometrial Lesions

Despite refinements in histologic criteria for the diagnosis of endometrioid precancers, many challenging cases are encountered in daily practice, creating diagnostic uncertainty and suboptimal patient management. Recently, an immunohistochemical 3-marker panel consisting of β-catenin, Pax2, and Pten was identified as a useful diagnostic adjunct. However, previous studies focused either on cancers or diagnostically unambiguous precancers, leaving questions about the applicability and utility of the panel in endometria with architectural features near or below the threshold of accepted histologic criteria for endometrioid precancers. Here, in a retrospective study of 90 patients, we evaluated the performance of the 3-marker panel. Notably, the panel detected a subset of disordered proliferative endometria (8/44, 18%), nonatypical hyperplasias (19/40, 48%), and cases with ambiguous features (3/6, 50%) with aberrancy for ≥1 markers. Marker-aberrant cases were more likely to progress to endometrioid precancer or cancer ( P =0.0002). Patterns of marker aberrancy in the index and progressor cases from individual patients provided evidence for origin in a common precursor, and next-generation sequencing of the progressor cases rationalized marker aberrancy for β-catenin and Pten. The results unequivocally demonstrate that some lesions that do not approach current histologic thresholds are bona fide neoplastic precursors with clinically-relevant driver events that can be detected by the 3-marker panel. The findings provide further validation for the diagnostic utility of the panel in clinical practice and its application in difficult or ambiguous cases.

Risk of atypical hyperplasia and endometrial carcinoma after initial diagnosis of non-atypical endometrial hyperplasia: A long-term follow-up study

OBJECTIVES

The strong association between atypical endometrial hyperplasia and endometrial carcinoma is well established, but data on the risk of atypical hyperplasia and carcinoma in Danish women with non-atypical endometrial hyperplasia are almost non-existent. This study aimed to investigate the prevalence of atypical hyperplasia and endometrial carcinoma diagnosed within 3 months of initial diagnosis (defined as concurrent disease) and the risk of atypical hyperplasia and carcinoma more than 3 months after initial diagnosis (classified as progressive disease) in Danish women initially diagnosed with non-atypical endometrial hyperplasia.

DESIGN

This cohort study recruited 102 women diagnosed with non-atypical endometrial hyperplasia at Randers Regional Hospital in Randers, Denmark, between 2000 and 2015.

METHODS

The endometrium was evaluated by transvaginal ultrasound examination and office mini-hysteroscopy with biopsies in all non-hysterectomized women. Data regarding subsequent hysterectomy or endometrial sampling were obtained from medical records and the Danish Pathology Registry (Patobank).

RESULTS

A total of 15 women were diagnosed with atypical hyperplasia or carcinoma during follow-up. Concurrent atypical hyperplasia or carcinoma was seen in 2.9% (3/102), and among women who remained at risk for more than 3 months after initial diagnosis of non-atypical endometrial hyperplasia (n = 94), progression to atypical hyperplasia or carcinoma was seen in 13% (median follow-up 5.2 years, range 3.6 months to 15.1 years). Sixty-six percent of the women with progressive disease were diagnosed with atypical hyperplasia or carcinoma more than 1 year after initial diagnosis, but only two were diagnosed later than 5 years (5.2 and 9 years).

CONCLUSIONS

The risk of being diagnosed with atypical endometrial hyperplasia or endometrial carcinoma more than 5 years after an initial diagnosis of non-atypical endometrial hyperplasia seems to be low in Danish women. Specialized follow-up more than 5 years after diagnosis of non-atypical endometrial hyperplasia may not be warranted.

Reliable Identification of Endometrial Precancers Through Combined Pax2, β-Catenin, and Pten Immunohistochemistry

The diagnosis of endometrial atypical hyperplasia/endometrioid intraepithelial neoplasia (AH/EIN) remains challenging and subjective in some cases, with variable histologic criteria and differences of opinion among gynecologic pathologists, potentially leading to under/overtreatment. There has been growing interest in the use of specific immunohistochemical markers as adjuncts in AH/EIN diagnosis. For example, the World Health Organization 2020 Classification specifies that loss of Pten, Pax2, or mismatch repair proteins are desirable diagnostic criteria. Other markers, most notably β-catenin and Arid1a, are also aberrantly expressed in some AH/EIN. However, the performance of some markers individually-and more importantly as a group-has not been rigorously explored, raising questions as to which marker(s) or combination(s) is the most effective in practice. Formalin-fixed paraffin-embedded tissue sections from AH/EIN cases (n=111) were analyzed by immunohistochemistry for 6 markers: Pax2, Pten, Mlh1, β-catenin, Arid1a, and p53. Aberrant expression was tabulated for each case and marker. An additional set of normal endometria (n=79) was also analyzed to define optimal diagnostic criteria for marker aberrance. The performance characteristics of each marker, the entire panel, and subsets thereof were quantitatively and statistically analyzed. In order of number of cases detected, the most frequently aberrant markers in AH/EIN were Pax2 (81.1% of cases), Pten (50.5%), β-catenin (47.7%), Arid1a (7.2%), Mlh1 (4.5%), and p53 (2.7%). The majority of cases showed aberrant expression of ≥2 markers. All 6 markers together identified 92.8% of cases. Arid1a, Mlh1, and p53 were robust and readily scored markers, but all cases showing aberrant expression of these 3 markers were also detected by Pax2, Pten, or β-catenin. A focused panel of only 3 markers (Pax2, Pten, and β-catenin) showed optimal performance characteristics as a diagnostic adjunct in the histopathologic diagnosis of AH/EIN. Use of this panel is practicable and robust, with at least 1 of the 3 markers being aberrant in 92.8% of AH/EIN.

Effects of Isoflavone Supplementation on the Response to Medroxyprogesterone in Premenopausal Women with Nonatypical Endometrial Hyperplasia: A Randomized, Double-Blind, Placebo-Controlled Trial

OBJECTIVE

The purpose of this study was to evaluate the impact of isoflavone supplementation compared with placebo on endometrial histology and serum estradiol levels in premenopausal women with nonatypical endometrial hyperplasia.

MATERIALS AND METHODS

The present double-blindplacebo-controlled clinical trial was conducted on 100 women with nonatypical endometrial hyperplasia in the age range of 30 to 45 years. Participants were randomly assigned to receive 50 mg of isoflavone (n = 50) or placebos (n = 50) daily for three months. Both groups received the standard treatment of nonatypical endometrial hyperplasia. Endometrial biopsy and blood samples were taken at the baseline and three months after the intervention. The incidence of drug side effects was assessed as well.

RESULTS

After three months, 88.4% of isoflavone-administered subjects had a significant histological improvement compared to 68.9% subjects in the placebo group (P=0.02). There were no significant differences between the two groups in the changes of serum estradiol levels and the incidence of drug side effects.

CONCLUSION

The findings of the present study demonstrated that the coadministration of 50 mg of isoflavones and medroxyprogesterone acetate increases the treatment efficacy in women with nonatypical endometrial hyperplasia. Clinical Trial Registration. This trial was registered on the Iranian website for clinical trial registration (https://www.irct.ir/trial/53553).

Histopathologic diagnosis of endometrial precancers: Updates and future directions

Early detection of endometrial cancer, especially its precancers, remains a critical and evolving issue in patient management and the quest to decrease mortality due to endometrial cancer. Due to many factors such as specimen fragmentation, the confounding influence of endogenous or exogenous hormones, and variable or overlapping histologic features, identification of bona fide endometrial precancers and their reliable discrimination from benign mimics remains one of the most challenging areas in diagnostic pathology. At the same time, the diagnosis of endometrial precancer, or the presence of suspicious but subdiagnostic features in an endometrial biopsy, can lead to long clinical follow-up with multiple patient visits and serial endometrial sampling, emphasizing the need for accurate diagnosis. Our understanding of endometrial precancers and their diagnosis has improved due to systematic investigations into morphologic criteria, the molecular genetics of endometrial cancer and their precursors, the validation of novel biomarkers and their use in panels, and more recent methods such digital image analysis. Although precancers for both endometrioid and non-endometrioid carcinomas will be reviewed, emphasis will be placed on the former. We review these advances and their relevance to the histopathologic diagnosis of endometrial precancers, and the recently updated 2020 World Health Organization (WHO) Classification of Female Genital Tumors.

Risk of More Advanced Lesions at Hysterectomy after Initial Diagnosis of Non-Atypical Endometrial Hyperplasia in Patients with Postmenopausal Bleeding and Oral Anticoagulant Treatment

Background and Objectives: Endometrial hyperplasia (EH) is a precursor lesion to endometrial cancer (EC), and when cellular atypia is present, in 40% of cases, they are diagnosed with EC on hysterectomy. Usually, EH is clinically manifested by uterine bleeding. In patients with oral anticoagulant therapy (OAT), the uterus is the second most common source of bleeding. The aim of the study was to show that uterine bleeding in postmenopausal patients undergoing OAT may reveal precancerous endometrial lesions with atypia, or neoplastic lesions in patients with an initial diagnosis of endometrial hyperplasia without atypia (non-atypical endometrial hyperplasia, NAEH) on dilation and curettage (D&C). We will be able to estimate the risk of a postmenopausal female patient with uterine bleeding during an OAT to have a precancerous endometrial lesion. Materials and Methods: The subjects of the study were 173 female patients with uterine bleeding, who have had total hysterectomy with bilateral salpingoovarectomy, of whom 99 underwent an OAT. There were 101 female patients initially diagnosed with NAEH, of which 60 did not have anticoagulant treatment (mean age 57.36 ± 6.51) and 41 had anticoagulant treatment (mean age 60.39 ± 7.35) (p = 0.006). From the pathology diagnosis moment, the surgery was performed at 42.09 ± 14.54 days in patients without OAT and after 35.39 ± 11.29 days in those who received such treatment (p = 0.724). Results: Initial diagnosis of NAEH established at D&C was changed at the final diagnosis after hysterectomy in EH with cellular atypia (atypical endometrial hyperplasia AEH) or EC in 18.18% of patients without OAT, and in 40.54% of patients who received this treatment. Conclusions: Based on a logistic regression model, it is estimated that female patients with an initial histopathological diagnosis of NAEH and who underwent OAT have, on average, 4.85 times greater odds (OR = 4.85, 95% CI 1.79–14.06) than the others of being identified postoperatively with more advanced lesions.

Novel diagnostic approaches to intrauterine neoplasm in fertile age: sonography and hysteroscopy

Endometrial carcinoma (EC) is the most common gynecological malignancy in the world. It is mostly detected in postmenopausal women, but it can also occur in women of fertile age who need fertility-sparing therapy. An early diagnosis is the main objective for the correct management of these patients, making it possible to use a fertility-sparing treatment approach without exposing the patients to the risk of cancer progression. In this review, we discuss the role of sonography and hysteroscopy in the detection of intrauterine neoplasm in women of childbearing age.

Route-specific association of progestin therapy and concurrent metformin use in obese women with complex atypical hyperplasia

INTRODUCTION

Previous studies have suggested that metformin use may enhance the therapeutic effect of progestin therapy for endometrial hyperplasia or malignancy. However, it is not known how the impact of concurrent metformin may be altered by route of progestin therapy, either locally via an intrauterine device or systemically. This study examined the effectiveness of concurrent metformin use and progestin therapy for women with complex atypical hyperplasia stratified by progestin route (systemic vs local).

METHODS

This single-institution retrospective study examined consecutive women with complex atypical hyperplasia who received progestin therapy from 2003 to 2018. Time-dependent analyses for complete response rate were performed comparing concurrent metformin users versus non-users in the oral progestin group and in the levonorgestrel-releasing intrauterine device group.

RESULTS

Across the study cohort (n=245), there were 137 (55.9%) women who responded to progestin therapy. In the oral progestin group (n=176), the median age and body mass index were 36 years and 37.7 kg/m2, respectively. 36 (20.5%) of women on oral progestins also took metformin. After controlling for diabetes status, women taking both oral progestins and metformin had a complete response rate similar to those not taking metformin (6 month cumulative rates, 23.1% vs 27.8%, adjusted hazard ratio (aHR) 0.71, 95% confidence interval (95% CI) 0.36 to 1.41). In the levonorgestrel-releasing intrauterine device group (n=69), the median age and body mass index were 35 years and 39.9 kg/m2, respectively. There were 15 (21.7%) women who took metformin in addition to the levonorgestrel-releasing intrauterine device. After controlling for diabetes status, women who had the levonorgestrel-releasing intrauterine device and took metformin had a significantly higher complete response rate compared with those not taking metformin (6 month cumulative rates, 86.7% vs 58.9%, aHR 2.31, 95% CI 1.09 to 4.89).

CONCLUSION

In a predominantly obese population, concurrent metformin may possibly offer treatment benefit when used with the levonorgestrel-releasing intrauterine device.

Expression of CD117, CD34, and VEGF proteins in progression from endometrial hyperplasia to endometrioid carcinoma

BACKGROUND

The risk of endometrial hyperplasia progressing into endometrioid carcinoma ranges from 1% for benign hyperplasia to 46.2% for endometrial intra-epithelial neoplasia. Differentiation between both types of hyperplasia is thus crucial for optimal management. The present study investigates the expression of the following immune-histochemical markers, for their potential roles in differentiating between both types of endometrial hyperplasia; as well as their expression in endometrial carcinoma: VEGF, CD34 and CD117.

METHODS

Tissue samples were obtained, fixed, processed, stained by hematoxylin and eosin for diagnosis, and then imunohistochemically stained using anti CD117, CD34, and VEGF antibodies.

RESULTS

In benign endometrial hyperplasia, the cells show weak expression to VEGF and CD34, and absent CD117. In endometrial intra-epithelial neoplasia, the cells show strong expression of VEGF and weak expression of CD34 and CD117. In case of endometrioid carcinoma, all cases showed strong reaction for VEGF and CD34, and moderate expression to CD117.

CONCLUSION

Our data suggests a role for CD117, CD34, and VEGF in progression from hyperplasia to carcinoma.

Long-term outcome of postmenopausal women with non-atypical endometrial hyperplasia on endometrial sampling

OBJECTIVE

To assess the long-term outcome of postmenopausal women diagnosed with non-atypical endometrial hyperplasia (NEH).

METHODS

This was a retrospective study of women aged 55 or older who underwent endometrial sampling in our academic medical center between 1997 and 2008. Women who had a current or recent (< 2 years) histological diagnosis of NEH were included in the study group and were compared with those diagnosed with atrophic endometrium (AE). Outcome data were obtained until February 2018. The main outcomes were risk of progression to endometrial carcinoma and risk of persistence, recurrence or new development of endometrial hyperplasia (EH) ('persistent EH'). Logistic regression analysis was used to identify covariates that were independent risk factors for progression to endometrial cancer or persistent EH.

RESULTS

During the study period, 1808 women aged 55 or older underwent endometrial sampling. The median surveillance time was 10.0 years. Seventy-two women were found to have a current or recent diagnosis of NEH and were compared with 722 women with AE. When compared to women with AE, women with NEH had significantly higher body mass index (33.9 kg/m² vs 30.6 kg/m² ; P = 0.01), greater endometrial thickness (10.00 mm vs 6.00 mm; P = 0.01) and higher rates of progression to type-1 endometrial cancer (8.3% vs 0.8%; P = 0.0003) and persistent NEH (22.2% vs 0.7%; P < 0.0001). They also had a higher rate of progression to any type of uterine cancer or persistent EH (33.3% vs 3.5%; P < 0.0001). Women with NEH had a significantly higher rate of future surgical intervention (51.4% vs 15.8%; P < 0.0001), including future hysterectomy (34.7% vs 9.8%; P < 0.0001). On multivariable logistic regression analysis, only NEH remained a significant risk factor for progression to endometrial cancer or persistence of EH.

CONCLUSIONS

Postmenopausal women with NEH are at significant risk for persistent EH and progression to endometrial cancer, at rates higher than those reported previously. Guidelines for the appropriate management of postmenopausal women with NEH are needed in order to decrease the rate of persistent disease or progression to cancer. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.

Endometrial development during the transition to menopause: preliminary associations with follicular dynamics

Objective: This study aimed to test the hypothesis that the development of functional luteal phase dominant follicles (LPDFs) is associated with increased endometrial growth as women transition to menopause.Methods: Endometrial thickness (ET), follicle development, and hormone production were characterized in ovulatory women of mid-reproductive age (MRA; 18-35 years, n = 10) and advanced reproductive age (ARA; 45-55 years, n = 16). Transvaginal ultrasonography was conducted every 1-3 days during one interovulatory interval to quantify ET and the diameters of follicles ≥2 mm. Blood was drawn at each visit to measure progesterone, estradiol, inhibin A, follicle stimulating hormone, and luteinizing hormone.Results: In the MRA group, ET was lower (8.87 vs. 10.1 mm) in women with typical versus no LPDFs, in association with greater luteal phase estradiol (91.1 vs. 48.8 ng/l). In the ARA group, luteal phase endometrial growth was greater (12.0 vs. 10.4 mm) in women with typical versus no LPDFs, in association with lower progesterone (10.7 vs. 13.8 μg/l; LPDF effect p < 0.1) and inhibin A (35.6 vs. 51.17 ng/l; p < 0.10).Conclusions: Preliminary findings suggest that ET may be increased in women who develop LPDFs, in association with reduced luteal phase progesterone and inhibin A, during the transition to menopause. Continued research is required to confirm these findings.

Development of A 3D Tissue Slice Culture Model for the Study of Human Endometrial Repair and Regeneration

The human endometrium undergoes sequential phases of shedding of the upper functionalis zone during menstruation, followed by regeneration of the functionalis zone from the remaining basalis zone cells, and secretory differentiation under the influence of the ovarian steroid hormones estradiol (E2) and progesterone (P4). This massive tissue regeneration after menstruation is believed to arise from endometrial stromal and epithelial stem cells residing in the basal layer of the endometrium. Although many endometrial pathologies are thought to be associated with defects in these stem cells, studies on their identification and regulation are limited, primarily due to lack of easily accessible animal models, as these processes are unique to primates. Here we describe a robust new method to study endometrial regeneration and differentiation processes using human endometrial tissue slice cultures incorporating an air-liquid interface into a 3D matrix scaffold of type I collagen gel, allowing sustained tissue viability over three weeks. The 3D collagen gel-embedded endometrial tissue slices in a double-dish culture system responded to ovarian steroid hormones, mimicking the endometrial changes that occur in vivo during the menstrual cycle. These changes included the E2-induced upregulation of Ki-67, estrogen receptor (ER), and progesterone receptor (PR) in all endometrial compartments and were markedly suppressed by both P4 and E2 plus P4 treatments. There were also distinct changes in endometrial morphology after E2 and P4 treatments, including subnuclear vacuolation and luminal secretions in glands as well as decidualization of stromal cells, typical characteristics of a progestational endometrium in vivo. This long-term slice culture method provides a unique in vivo-like microenvironment for the study of human endometrial functions and remodeling during early pregnancy and experiments on stem cell populations involved in endometrial regeneration and remodeling. Furthermore, this model has the potential to enable studies on several endometrial diseases, including endometrial cancers and pregnancy complications associated with defects in endometrial remodeling.

Pyruvate Kinase M2 Expression: A Potential Metabolic Biomarker to Differentiate Endometrial Precancer and Cancer That Is Associated with Poor Outcomes in Endometrial Carcinoma

Background: Pyruvate kinase M2 (PKM2) is a regulator of the processes of glycolysis and oxidative phosphorylation, but the roles that it plays in endometrial cancer remain largely unknown. This study evaluated the PKM2 expression in normal endometrium, endometrial hyperplasia, and endometrial carcinoma, and its prognostic value was investigated in endometrial carcinoma patients. Methods: A hospital-based retrospective review was conducted to examine the immunohistochemical PKM2 distribution in 206 endometrium samples from biopsies or hysterectomies. The immunoreactivity of PKM2 was divided into groups of low and high scores according to the extent and intensity of staining. Results: Intense cytoplasmic staining was observed for the PKM2 protein in malignant endometrial lesions. A high PKM2 score was observed in many endometrial carcinoma samples (50.0%), but there was a low percentage in endometrial atypical hyperplasia (12.5%). High PKM2 expression was not found in the normal endometrium (0.0%) nor endometrial hyperplasia without atypia (0.0%). The PKM2 protein score was significantly higher in endometrial carcinoma samples than premalignant endometrial lesions (p < 0.001). Notably, higher PKM2 scores in cases of endometrial carcinoma correlated with poor overall survival (p = 0.006), and the hazard ratio for death was 3.40 (95% confidence interval, 1.35–8.56). Conclusions: Our results indicate that the prevalence of PKM2^high tumor cells in endometrial carcinoma is significantly associated with worse prognostic factors and favors a poor prognosis. The expression of PKM2 is also a potential histopathological biomarker for use in the differential diagnosis of malignant and premalignant endometrial lesions.

Benign and Premalignant Lesions of the Endometrium

In this review, we highlight the benign and premalignant lesions of the endometrium that the pathologist may encounter in daily practice. We begin by detailing our current understanding of excess estrogen in the progression of endometrial neoplasia. We outline the currently accepted terminology to be used when evaluating proliferative endometrial lesions, while highlighting their key features. Attention is then turned to the molecular underpinnings of neoplastic progression and how this can be exploited with immunohistochemical stains when appropriate. Finally, we discuss types of metaplasia and their associations, including so-called papillary proliferations of the endometrium.

Endometrial hyperplasia and the risk of coexistent cancer: WHO versus EIN criteria

Endometrial hyperplasia (EH) is classified into benign and precancerous according to two different histomorphological systems: the World Health Organisation (WHO) system (based on the subjective evaluation of cytological atypia) and the endometrial intraepithelial neoplasia (EIN) system (based on a combination of several parameters that are assessable subjectively, or objectively through computerised analysis). The American College of Obstetricians and Gynecologists recommends use of the EIN system. Nonetheless, a higher prognostic value for EIN criteria was demonstrated only with the objective assessment, which is not routinely applicable. The aim of this study was to evaluate which of the subjective classifications of EH (WHO or EIN) has better prognostic value, by assessing the risk of coexistent cancer. Electronic databases were searched for relevant articles from the inception of the databases to July 2018. All studies assessing the presence of cancer on hysterectomy specimens after a preoperative histological diagnosis of EH were included. Odds ratios (ORs), sensitivity and specificity were calculated with 95% confidence intervals (CIs). Sixteen cohort studies and three case-control studies, assessing 2582 EHs, were included. The WHO criteria showed an OR of 11.15 (95% CI 7.65-16.24), a sensitivity of 0.86 (95% CI 0.82-0.90) and a specificity of 0.67 (95% CI 0.64-0.70) for coexistent cancer. The subjective EIN system showed a similar OR (11.85, 95% CI 4.91-28.62; P = 0.90), higher sensitivity (0.98, 95% CI 0.94-0.99), and lower specificity (0.29, 95% CI 0.24-0.34). The WHO system and the subjective EIN system have similar prognostic values. However, the EIN criteria appear to be more sensitive and thus more suitable for selecting women who need to be treated, whereas the WHO criteria, based on cytological atypia, seem to be more specific for lesions at higher risk of cancer. Therefore, integration of the EIN system with cytological atypia should be considered.

Second Opinion Expert Pathology in Endometrial Cancer: Potential Clinical Implications

OBJECTIVE

In cancer patients, the pathology report serves as an important basis for treatment. Therefore, a correct cancer diagnosis is crucial, and diagnostic discrepancies may be of clinical relevance. It was the aim of this study to perform a specialized histopathology review and to investigate potential clinical implications of expert second opinion pathology in endometrial cancer.

METHODS

Patients treated for endometrial carcinoma at the Tübingen University Women's hospital between 2003 and 2013 were identified. Original pathology reports were reviewed, and contributing pathologists were asked to submit original slides and paraffin blocks. Case review was subsequently performed by 3 pathologists specialized in gynecological pathology who were blinded for clinical information. For histological typing, the World Health Organization 2014 classification was used, grading and staging were performed according to International Federation of Gynecology and Obstetrics 2009. Risk assignment was performed based on the 2013 European Society for Medical Oncology clinical practice guidelines.

RESULTS

In 565 of 745 cases, which had originally been diagnosed as endometrial carcinoma, archival histological slides and blocks were available. In 55 (9.7%) of 565 cases, a major diagnostic discrepancy of potential clinical relevance was found after expert review. In 38 of these 55 cases, the diagnostic discrepancy was related to tumor type (n = 24), grade (n = 10) or myoinvasion (n = 4). In 17 cases, the diagnosis of endometrial carcinoma could not be confirmed (atypical hyperplasia, n = 10; endometrial carcinosarcoma, n = 4; neuroendocrine carcinoma, n = 1; leiomyosarcoma, n = 1; atypical polypoid adenomyoma, n = 1). Minor discrepancies not changing risk classification were also noted in 214 (37.9%) of 565, most frequently for grade within the low-grade (G1/G2) category (n = 184).

CONCLUSIONS

A retrospective gynecopathological case review was shown to reveal limited but significant discrepancies in histological diagnoses as well as typing and grading of endometrial carcinomas, some directly impacting clinical management. Second opinion pathology therefore not only helps to improve the quality of translational research study cohorts but might also help to optimize patient care in difficult cases.

New classification system of endometrial hyperplasia WHO 2014 and its clinical implications

Endometrial hyperplasia (EH) is a pathological condition characterised by hyperplastic changes in endometrial glandular and stromal structures lining the uterine cavity. Endometrial hyperplasia, particularly with atypia, is a significant clinical concern because it can be a precursor of endometrial cancer. Accurate diagnosis of precancerous lesions of the endometrium and exclusion of coexisting endometrial carcinomas are absolutely required for the optimal management of patients. The classification of endometrial hyperplasia has had numerous terminology. According to the classification of WHO94, based on glandular complexity and nuclear atypia, EH is divided into four groups: non-atypical endometrial hyperplasia (simple, complex) and atypical endometrial hyperplasia (simple, complex). Estimated risk of progression of atypical hyperplasia to endometrial cancer is 8-29%. The American College of Obstetricians and Gynaecologists and the Society of Gynaecological Oncology states that endometrial intraepithelial neoplasia (EIN) classification is superior to the World Health Organisation (WHO 94) classification for histology of endometrial hyperplasia. However, the WHO classification system remains the most commonly used and reported in existing literature.

The new classification, WHO 2014, accepted by the International Society of Gynaecological Pathologists, divided hyperplasia into two groups: benign hyperplasia and atypical hyperplasia/endometrial intraepithelial neoplasia (EIN). The WHO 2014 schema is more likely to successfully identify precancerous lesions than the WHO94 classification.

CTCF genetic alterations in endometrial carcinoma are pro-tumorigenic

CTCF is a haploinsufficient tumour suppressor gene with diverse normal functions in genome structure and gene regulation. However the mechanism by which CTCF haploinsufficiency contributes to cancer development is not well understood. CTCF is frequently mutated in endometrial cancer. Here we show that most CTCF mutations effectively result in CTCF haploinsufficiency through nonsense-mediated decay of mutant transcripts, or loss-of-function missense mutation. Conversely, we identified a recurrent CTCF mutation K365T, which alters a DNA binding residue, and acts as a gain-of-function mutation enhancing cell survival. CTCF genetic deletion occurs predominantly in poor prognosis serous subtype tumours, and this genetic deletion is associated with poor overall survival. In addition, we have shown that CTCF haploinsufficiency also occurs in poor prognosis endometrial clear cell carcinomas and has some association with endometrial cancer relapse and metastasis. Using shRNA targeting CTCF to recapitulate CTCF haploinsufficiency, we have identified a novel role for CTCF in the regulation of cellular polarity of endometrial glandular epithelium. Overall, we have identified two novel pro-tumorigenic roles (promoting cell survival and altering cell polarity) for genetic alterations of CTCF in endometrial cancer.

[Pitfalls in the histopathological diagnostics of endometrial carcinoma and its precursors : Clinically relevant differential diagnoses, avoidance of false positive diagnoses]

Making an incorrect histopathological diagnosis of an endometrial lesion may lead to unwanted loss of fertility and therapy-associated morbidity; therefore, endometrial carcinomas need to be correctly typed and differentiated from hyperplastic precursors, benign lesions and artifacts. Typical diagnostic pitfalls are described in this article. Misdiagnosing endometrial lesions can be avoided by paying thorough attention to gross as well as microscopic features and by taking crucial differential diagnoses into consideration. These are, in particular, well-differentiated endometrioid adenocarcinoma of the endometrium versus atypical endometrial hyperplasia, myoinvasive endometrioid adenocarcinoma versus atypical polypoid adenomyoma and endometrioid carcinoma versus serous carcinoma of the endometrium with a predominantly glandular pattern. It is also important to consider the possibility of a false positive diagnosis of atypical endometrial hyperplasia or carcinoma in cases of biopsy-induced artifacts.

Prediction of concurrent endometrial carcinoma in women with endometrial hyperplasia

OBJECTIVE

Although a fraction of endometrial hyperplasia cases have concurrent endometrial carcinoma, patient characteristics associated with concurrent malignancy are not well described. The aim of our study was to identify predictive clinico-pathologic factors for concurrent endometrial carcinoma among patients with endometrial hyperplasia.

METHODS

A case-control study was conducted to compare endometrial hyperplasia in both preoperative endometrial biopsy and hysterectomy specimens (n=168) and endometrial carcinoma in hysterectomy specimen but endometrial hyperplasia in preoperative endometrial biopsy (n=43). Clinico-pathologic factors were examined to identify independent risk factors of concurrent endometrial carcinoma in a multivariate logistic regression model.

RESULTS

The most common histologic subtype in preoperative endometrial biopsy was complex hyperplasia with atypia [CAH] (n=129) followed by complex hyperplasia without atypia (n=58) and simple hyperplasia with or without atypia (n=24). The majority of endometrial carcinomas were grade 1 (86.0%) and stage I (83.7%). In multivariate analysis, age 40-59 (odds ratio [OR] 3.07, p=0.021), age≥60 (OR 6.65, p=0.005), BMI≥35kg/m(2) (OR 2.32, p=0.029), diabetes mellitus (OR 2.51, p=0.019), and CAH (OR 9.01, p=0.042) were independent predictors of concurrent endometrial carcinoma. The risk of concurrent endometrial carcinoma rose dramatically with increasing number of risk factors identified in multivariate model (none 0%, 1 risk factor 7.0%, 2 risk factors 17.6%, 3 risk factors 35.8%, and 4 risk factors 45.5%, p<0.001). Hormonal treatment was associated with decreased risk of concurrent endometrial cancer in those with ≥3 risk factors.

CONCLUSIONS

Older age, obesity, diabetes mellitus, and CAH are predictive of concurrent endometrial carcinoma in endometrial hyperplasia patients.

DNA methylation as a biomarker for the detection of hidden carcinoma in endometrial atypical hyperplasia

OBJECTIVE

Women with atypical hyperplasia (AH) are often found to have endometrial carcinoma (EC) at hysterectomy. The purpose of this study was to evaluate whether the hypermethylation of specific genes found by methylomic approaches to the study of gynecologic cancers is a biomarker for EC in women with AH.

METHODS

We evaluated the methylation of AJAP1, HS3ST2, SOX1, and PTGDR from 61 AH patients undergoing hysterectomy. Endometrial biopsy samples were analyzed by bisulfite conversion and quantitative methylation-specific polymerase chain reaction. A methylation index was used to predict the presence of cancer. To confirm the silencing effects of DNA methylation, immunohistochemical analysis of AJAP1, HS3ST2, and SOX1 was performed using tissue microarray.

RESULTS

Fourteen (23%) patients had EC at hysterectomy. AJAP1, HS3ST2, and SOX1 were highly methylated in the EC patients' biopsy samples (p≤0.023). AJAP1, HS3ST2, and SOX1 protein expression was significantly higher in patients with AH only (p≤0.038). The predictive value of AJAP1, HS3ST2, and SOX1 methylation for EC was 0.81, 0.72, and 0.70, respectively. Combined testing of both AJAP1 and HS3ST2 methylation had a positive predictive value of 56%, methylation of any one of AJAP1, SOX1, or HS3ST2 had a 100% negative predictive value.

CONCLUSIONS

Hypermethylation of AJAP1, HS3ST2, and SOX1 is predictive of EC in AH patients. Testing for methylation of these genes in endometrial biopsy samples may be a hysterectomy-sparing diagnostic tool. Validation of these new genes as biomarkers for AH screening in a larger population-based study is warranted.

Clinically significant endometrial cancer risk following a diagnosis of complex atypical hyperplasia

OBJECTIVES

Because of the frequent detection of carcinoma in surgical specimens after hysterectomy for endometrial complex atypical hyperplasia (CAH), it has been suggested that patients with a preoperative diagnosis of CAH be referred to gynecologic oncology for potential lymphadenectomy. However, the risk of lymph node metastasis in such patients is unknown. We sought to determine the risk of endometrial cancer and to estimate the risk of lymphatic spread in women with a preoperative diagnosis of CAH.

STUDY DESIGN

We retrospectively reviewed the medical records of 150 consecutive patients with a preoperative diagnosis of CAH who subsequently underwent hysterectomy. Clinical characteristics and pathologic information were abstracted. Risk of lymphatic spread was modeled using previously published criteria and nomograms.

RESULTS

Fifty-five of the 150 patients (36.7%) had an incidental endometrial carcinoma at the time of hysterectomy. Among patients with a preoperative office biopsy compared to dilation and curettage, the rate of an incidental finding of cancer was 43.5% and 28.1%, respectively (p=0.054). Of patients with cancer, 1 (1.8%) had a grade 3 endometrial carcinoma, 4 (7.3%) had lymphovascular space involvement, and 6 (10.9%) had deep (>50%) myometrial invasion. For the 10 patients who underwent lymphadenectomy, one (10%) had lymph node metastases. Based on multiple models, the estimated risk of lymph node spread was 1.6%-2.1% for all women with a preoperative diagnosis of CAH and 4.4%-6.8% for the 55 women with endometrial cancer.

CONCLUSIONS

Given the high rates of underlying endometrial cancer and the potential need for lymphadenectomy, care for patients with a preoperative diagnosis of CAH desiring definitive management with hysterectomy should be referred to a gynecologic oncologist.

Endometrial intraepithelial neoplasia

CONTEXT

Developed in conjunction with molecular and progression data, the sequence classification schema for endometrial intraepithelial neoplasia (EIN)/benign hyperplasia (BH) provides an easy to adopt and reproducible method for classification of endometrial biopsies.

OBJECTIVE

To review current data supporting the use of BH/EIN to classify endometrial biopsies, and to discuss the hormone-driven endometrial sequence from anovulation/disordered proliferative endometrium through BH and EIN and their diagnostic difficulty.

DATA SOURCES

A comprehensive review of EIN literature based on literature indexed by PubMed (National Library of Medicine) and Google Scholar.

CONCLUSIONS

The BH/EIN schema is gaining wider acceptance among pathologist and clinicians. The research leading to the EIN criteria is based on molecular and progression data. The BH/EIN schema has better reproducibility among pathologists, is intuitively easy to use, and requires understanding of endometrial physiology and neoplasia.

Understanding diagnostic variability in breast pathology: lessons learned from an expert consensus review panel

AIMS

To gain a better understanding of the reasons for diagnostic variability, with the aim of reducing the phenomenon.

METHODS AND RESULTS

In preparation for a study on the interpretation of breast specimens (B-PATH), a panel of three experienced breast pathologists reviewed 336 cases to develop consensus reference diagnoses. After independent assessment, cases coded as diagnostically discordant were discussed at consensus meetings. By the use of qualitative data analysis techniques, transcripts of 16 h of consensus meetings for a subset of 201 cases were analysed. Diagnostic variability could be attributed to three overall root causes: (i) pathologist-related; (ii) diagnostic coding/study methodology-related; and (iii) specimen-related. Most pathologist-related root causes were attributable to professional differences in pathologists' opinions about whether the diagnostic criteria for a specific diagnosis were met, most frequently in cases of atypia. Diagnostic coding/study methodology-related root causes were primarily miscategorizations of descriptive text diagnoses, which led to the development of a standardized electronic diagnostic form (BPATH-Dx). Specimen-related root causes included artefacts, limited diagnostic material, and poor slide quality. After re-review and discussion, a consensus diagnosis could be assigned in all cases.

CONCLUSIONS

Diagnostic variability is related to multiple factors, but consensus conferences, standardized electronic reporting formats and comments on suboptimal specimen quality can be used to reduce diagnostic variability.

Feasibility of RNA and DNA extraction from fresh pipelle and archival endometrial tissues for use in gene expression and SNP arrays

Identifying molecular markers of endometrial hyperplasia (neoplasia) progression is critical to cancer prevention. To assess RNA and DNA quantity and quality from routinely collected endometrial samples and evaluate the performance of RNA- and DNA-based arrays across endometrial tissue types, we collected fresh frozen (FF) Pipelle, FF curettage, and formalin-fixed paraffin-embedded (FFPE) hysterectomy specimens (benign indications) from eight women. Additionally, neoplastic and uninvolved tissues from 24 FFPE archival hysterectomy specimens with endometrial hyperplasias and carcinomas were assessed. RNA was extracted from 15 of 16 FF and 51 of 51 FFPE samples, with yields >1.2 μg for 13/15 (87%) FF and 50/51 (98%) FFPE samples. Extracted RNA was of high quality; all samples performed successfully on the Illumina whole-genome cDNA-mediated annealing, selection, extension, and ligation (WG-DASL) array and performance did not vary by tissue type. While DNA quantity from FFPE samples was excellent, quality was not sufficient for successful performance on the Affymetrix SNP Array 6.0. In conclusion, FF Pipelle samples, which are minimally invasive, yielded excellent quantity and quality of RNA for gene expression arrays (similar to FF curettage) and should be considered for use in genomic studies. FFPE-derived DNA should be evaluated on new rapidly evolving sequencing platforms.

Management of endometrial precancers

In the United States, endometrial cancer is the most commonly diagnosed cancer of the female reproductive system. Strategies to sensitively and accurately diagnose premalignant endometrial lesions are sorely needed. We reviewed studies pertaining to the diagnostic challenges of endometrial precancers, their predictive value, and evidence to support management strategies. Currently, two diagnostic schemas are in use: the four-class 1994 World Health Organization hyperplasia system, based on morphologic features of architectural complexity and nuclear atypia and, more recently, the two-class endometrial intraepithelial neoplasia system, which is quantitative. Diagnosis should use criteria and terminology that distinguish between clinicopathologic entities that can be managed differently. In some instances, such as for women with hereditary nonpolyposis colon cancer, biomarkers may aid in diagnosis, but the clinical utility of biomarkers has yet to be determined. Total hysterectomy is curative for atypical endometrial hyperplasia or endometrial intraepithelial neoplasia, and provides a definitive standard for assessment of a concurrent carcinoma, when clinically appropriate. If hysterectomy is performed for atypical endometrial hyperplasia or endometrial intraepithelial neoplasia, then intraoperative assessment of the uterine specimen for occult carcinoma is desirable, but optional. Nonsurgical management may be appropriate for patients who wish to preserve fertility or those for whom surgery is not a viable option. Treatment with progestin therapy may provide a safe alternative to hysterectomy; however, clinical trials of hormonal therapies for atypical endometrial hyperplasia or endometrial intraepithelial neoplasia have not yet established a standard regimen. Future studies will need to determine the optimal nonsurgical management of atypical endometrial hyperplasia or endometrial intraepithelial neoplasia, standardizing agent, dose, schedule, clinical outcomes, and appropriate follow-up.

The problem of colliding networks and its relation to cell fusion and cancer

Cell fusion, a process that merges two or more cells into one, is required for normal development and has been explored as a tool for stem cell therapy. It has also been proposed that cell fusion causes cancer and contributes to its progression. These functions rely on a poorly understood ability of cell fusion to create new cell types. We suggest that this ability can be understood by considering cells as attractor networks whose basic property is to adopt a set of distinct, stable, self-maintaining states called attractors. According to this view, fusion of two cell types is a collision of two networks that have adopted distinct attractors. To learn how these networks reach a consensus, we model cell fusion computationally. To do so, we simulate patterns of gene activities using a formalism developed to simulate patterns of memory in neural networks. We find that the hybrid networks can assume attractors that are unrelated to parental attractors, implying that cell fusion can create new cell types by nearly instantaneously moving cells between attractors. We also show that hybrid networks are prone to assume spurious attractors, which are emergent and sporadic network states. This finding means that cell fusion can produce abnormal cell types, including cancerous types, by placing cells into normally inaccessible spurious states. Finally, we suggest that the problem of colliding networks has general significance in many processes represented by attractor networks, including biological, social, and political phenomena.

Management of endometrial precancers

In the United States, endometrial cancer is the most commonly diagnosed cancer of the female reproductive system. Strategies to sensitively and accurately diagnose premalignant endometrial lesions are sorely needed. We reviewed studies pertaining to the diagnostic challenges of endometrial precancers, their predictive value, and evidence to support management strategies. Currently, two diagnostic schemas are in use: the four-class 1994 World Health Organization hyperplasia system, based on morphologic features of architectural complexity and nuclear atypia and, more recently, the two-class endometrial intraepithelial neoplasia system, which is quantitative. Diagnosis should use criteria and terminology that distinguish between clinicopathologic entities that can be managed differently. In some instances, such as for women with hereditary nonpolyposis colon cancer, biomarkers may aid in diagnosis, but the clinical utility of biomarkers has yet to be determined. Total hysterectomy is curative for atypical endometrial hyperplasia or endometrial intraepithelial neoplasia, and provides a definitive standard for assessment of a concurrent carcinoma, when clinically appropriate. If hysterectomy is performed for atypical endometrial hyperplasia or endometrial intraepithelial neoplasia, then intraoperative assessment of the uterine specimen for occult carcinoma is desirable, but optional. Nonsurgical management may be appropriate for patients who wish to preserve fertility or those for whom surgery is not a viable option. Treatment with progestin therapy may provide a safe alternative to hysterectomy; however, clinical trials of hormonal therapies for atypical endometrial hyperplasia or endometrial intraepithelial neoplasia have not yet established a standard regimen. Future studies will need to determine the optimal nonsurgical management of atypical endometrial hyperplasia or endometrial intraepithelial neoplasia, standardizing agent, dose, schedule, clinical outcomes, and appropriate follow-up.

Expression of thyroid transcription factor-1 in normal endometrium is associated with risk of endometrial cancer development

Thyroid transcription factor-1 (TTF-1) is a DNA-binding protein that is mainly expressed in thyroid and lung tissue, but has also been found in gynecologic tissue. Recent studies have suggested that TTF-1 has tumor suppressor function in lung adenocarcinoma models. In the current study, we examined whether expression of TTF-1 in benign endometrium and endometrial hyperplasia might impact on the risk of developing endometrial cancer. Formalin-fixed paraffin-embedded endometrial tissues obtained from 535 cases were used to construct an endometrial tissue microarray. One hundred fifty of 207 patients had multiple serial endometrial specimens including 46 patients who progressed to endometrial cancer. The tissue microarray included a range of histopathologies including benign endometrium (n=231), simple hyperplasia (n=105), complex hyperplasia (n=36), simple atypical hyperplasia (n=10), complex atypical hyperplasia (n=44), and endometrial carcinoma (n=109). Expression of TTF-1 by immunohistochemistry in benign endometrium and endometrial hyperplasia was correlated with progression to cancer and clinical features known to be associated with increased risk of developing endometrial cancer. Carcinoma specimens showed a significantly greater expression of TTF-1 compared with benign endometrium and non-atypical hyperplasia (P=0.0007 and P=0.05). Presence of TTF-1 expression in benign endometrium was associated with a significantly decreased risk of cancer development (P=0.003, hazards ratio=0.104, 95% CI: 0.024-0.455). TTF-1 expression in hyperplasia did not significantly correlate with progression to cancer. The data from our study show that TTF-1 expression in normal endometrium is associated with a reduced risk of endometrial cancer development. This observation suggests that TTF-1 might function as a tumor suppressor in endometrial tissue. TTF-1 expression in normal endometrium could potentially provide clinically useful information as a biomarker for the risk of endometrial cancer.

Biomarkers of progestin therapy resistance and endometrial hyperplasia progression

OBJECTIVE

We sought to identify biomarkers associated with progestin therapy resistance and persistence/progression of endometrial hyperplasia.

STUDY DESIGN

We performed a nested case-control study among women with complex (n = 73) and atypical (n = 41) hyperplasia treated with oral progestin, followed up 2-6 months for persistence/progression. We evaluated index endometrial protein expression for progesterone receptor isoform A, progesterone receptor isoform B (PRB), PTEN, Pax-2, and Bcl-2. Odds ratios and 95% confidence intervals (CIs) were estimated.

RESULTS

Among women with atypical hyperplasia, high PRB expression was associated with 90% decreased risk of persistence/progression (95% CI, 0.01-0.8). High expression of progesterone receptor A and PRB suggested decreased risk of persistence/progression (odds ratio, 0.1; 95% CI, 0.02-1.0). These findings were not observed among women with complex hyperplasia. No associations were found with PTEN, Pax-2, and Bcl-2 protein expression.

CONCLUSION

PRB expression shows promise as a biomarker of progestin response. Further research is warranted to understand how PRB expression may guide treatment decisions.

PAX2 loss by immunohistochemistry occurs early and often in endometrial hyperplasia

Immunohistochemical markers to assist in the diagnosis and classification of hyperplastic endometrial epithelial proliferations would be of diagnostic use. To examine the possible use of PAX2 as a marker of hyperplastic endometrium, cases of normal endometrium, simple and complex hyperplasia without atypia, atypical hyperplasia, and International Federation of Gynecology and Obstetrics (FIGO) grade 1 endometrioid carcinomas were stained for PAX2. Two hundred and six endometrial samples were available for interpretation of PAX2 staining. The percentage of cases with complete PAX2 loss (0% of cells staining) increased with increasing severity of hyperplasia: 0% of normal proliferative and secretory endometrium (n=28), 17.4% of simple hyperplasia (n=23), 59.0% of complex hyperplasia (n=83), 74.1% of atypical hyperplasia (n=54), and 73.3% of FIGO grade 1 endometrioid cancers (n=15). Partial loss of PAX2 expression did occur in normal endometrium (17.9%) but in smaller proportions of tissue and was less frequent than in simple hyperplasia (47.8% with partial loss), complex hyperplasia (32.5%), atypical hyperplasia (22.2%), and FIGO grade 1 carcinomas (20.0%). Uniform PAX2 expression was rare in complex (8.4%) and atypical hyperplasia (3.7%) and carcinoma (6.7%). When evaluating loss of PAX2 in histologically normal endometrium adjacent to lesional endometrium in a given case, statistically significant differences in staining were observed for simple hyperplasia (P=0.011), complex hyperplasia (P<0.001), atypical hyperplasia (P<0.001), and FIGO grade 1 endometrioid cancer (P=0.003). In summary, PAX2 loss seems to occur early in the development of endometrial precancers and may prove useful in some settings as a diagnostic marker in determining normal endometrium from complex and atypical hyperplasia and low-grade carcinomas. However, it is not useful in distinguishing between these diagnostic categories.

Molecular biomarkers in endometrial hyperplasias predict cancer progression

OBJECTIVE

The purpose of this study was to assess the value of the 2003 World Health Organization (WHO) and endometrial intraepithelial neoplasia (EIN) classifications, D-score, and molecular biomarkers in endometrial hyperplasia (EH) for cancer progression.

STUDY DESIGN

We conducted a review of 307 endometrial hyperplasias for WHO and EIN classifications and an analysis of biomarkers, D-score, and cancer progression-free survival.

RESULTS

The WHO, EIN, D-score, and many biomarkers were prognostic; 7.2% of the samples progressed to cancer. The WHO and EIN classifications correlated weakly with CK5/6 and p16. The D-score was strongest prognostically. When >1, it had the lowest false-negative progression rate of all features analyzed. COX2 negativity was the only other independent multivariate cancer progression predictor in endometrial hyperplasia, but only in cases with D-score <1. Eight of 13 cases (61%), with a combined D-score of <1 and negative COX2 progressed, which contrasted with 3 of 139 of all other cases (2.8%) (P < .0001; hazard ratio, 53.0). The biomarkers did not strengthen the prognostic value of the WHO or EIN classification.

CONCLUSION

Combined D-score <1 and COX2 negativity strongly predict cancer progression in endometrial hyperplasias.

Epithelial membrane protein-2 expression is an early predictor of endometrial cancer development

BACKGROUND

Endometrial cancer (EC) is a common malignancy worldwide. It is often preceded by endometrial hyperplasia, whose management and risk of neoplastic progression vary. Previously, the authors have shown that the tetraspan protein epithelial membrane protein-2 (EMP2) is a prognostic indicator for EC aggressiveness and survival. Here the authors validate the expression of EMP2 in EC, and further examine whether EMP2 expression within preneoplastic lesions is an early prognostic biomarker for EC development.

METHODS

A tissue microarray (TMA) was constructed with a wide representation of benign and malignant endometrial samples. The TMA contains a metachronous cohort of cases from individuals who either developed or did not develop EC. Intensity and frequency of EMP2 expression were assessed using immunohistochemistry.

RESULTS

There was a stepwise, statistically significant increase in the average EMP2 expression from benign to hyperplasia to atypia to EC. Furthermore, detailed analysis of EMP2 expression in potentially premalignant cases demonstrated that EMP2 positivity was a strong predictor for EC development.

CONCLUSIONS

EMP2 is an early predictor of EC development in preneoplastic lesions. In addition, combined with our previous findings, these results validate EMP2 as a novel biomarker for EC development.

PTEN-loss and nuclear atypia of EIN in endometrial biopsies can predict the existence of a concurrent endometrial carcinoma

AIM

The objective of the present study was to evaluate whether nuclear atypia or PTEN-loss in endometrial intraepithelial neoplasia (EIN), could help to predict in endometrial curettage material, the prevalence of concurrent carcinoma in hysterectomy specimens.

MATERIALS AND METHODS

This retrospective single-institution study included women who were diagnosed with endometrial hyperplasia (simple or complex) and underwent hysterectomy within 12weeks from the initial diagnosis without interval treatment. All endometrial curettage slides were reviewed by three experienced pathologists and only cases that fulfilled the criteria of EIN were used for further analysis. For each case, the nuclear atypia and the immunohistochemically detected expression of PTEN were evaluated. The hysterectomy slides were also reviewed and the findings were used in the subsequent analysis.

RESULTS

Out of 83 cases that were enrolled in the study, 33 (39.76%), had a concurrent endometrial carcinoma. Nuclear atypia in EIN cases with a final histology of endometrial cancer was found in 31 out of 33 cases (93.94%) but only in 27 out of 50 benign cases (54%). There was no PTEN-loss in 8 out of 33 EIN cases (24.24%) that proved to be cancer and 22 out of 50 EIN cases (44%) that proved to be benign. Either atypia or PTEN-loss or both were found in 33/33 (100%) cancer cases and in 39/50 (78%) benign cases; this difference was statistically significant (Fisher exact test, p < 0.05).

CONCLUSION

PTEN-loss, as an independent variable, was not found to be a predictor of endometrial cancer in the final histology. However, biopsies presented with EIN, featuring nuclear atypia and recognized as PTEN-null are more likely to be finally diagnosed with endometrial cancer.

Genistein aglycone: a new therapeutic approach to reduce endometrial hyperplasia

OBJECTIVE

Endometrial hyperplasia without cytological atypia is commonly treated with progestins, but other treatment regimes may be available with equivalent efficacy and low side effects.

DESIGN

A randomized double-blind, placebo and progesterone-controlled clinical trial to evaluate the effects of genistein aglycone in reducing endometrial hyperplasia.

PATIENTS

A group of 56 premenopausal women with non-atypical endometrial hyperplasia were enrolled and received: genistein aglycone (n=19; 54 mg/day); norethisterone acetate (n=19; 10 mg/day on days 16-25 of the menstrual cycle) or placebo (n=18) for 6 months.

MEASUREMENTS

Hysteroscopy was performed with biopsies and symptomology assessed at baseline, 3 and 6 months of administration. The effect on estrogen (ER) and progesterone receptors (PR) expression in uterine biopsies were assessed after 3 and 6 months. For each treatment follicle stimulating hormone (FSH), luteinizing hormone (LH), estradiol (E2), sex hormone-binding globulin (SHBG) and progesterone (PG) levels were also evaluated.

RESULTS

After 6 months, 42% of genistein aglycone-administered subjects had a significant improvement of symptoms (histologically confirmed in the 29%) compared to 47% of norethisterone acetate subjects (histologically confirmed in the 31%), but only 12% in the placebo group with 19% exhibiting worsening symptoms and increased endometrial thickness. No significant differences were noted for hormone levels for any treatment, but immunohistochemical analysis revealed significantly reduced staining for ER-alpha and PR and enhanced ER-beta1 staining in genistein-administered subjects associated with a complete regression of bleeding.

CONCLUSIONS

These results suggest that genistein aglycone might be useful for the management of endometrial hyperplasia without atypia in women that cannot be treated with progestin.

Complex hyperplasia with and without atypia: clinical outcomes and implications of progestin therapy

OBJECTIVE

Limited data exist to inform clinicians and patients as to the likelihood of long-term endometrial hyperplasia response to progestin therapy, especially for atypical hyperplasia. We evaluated women with complex and atypical endometrial hyperplasia, comparing those prescribed progestin with those not prescribed progestin.

METHODS

This retrospective cohort study was conducted in 1985-2005 among women aged 18-88 years at an integrated health plan in Washington State. Women were ineligible if they achieved an outcome (endometrial carcinoma, hysterectomy, or both) within 8 weeks of hyperplasia diagnosis. Exposure was progestin use for at least 14 days by duration and recency. Outcomes included rate of 1) endometrial carcinoma, 2) hysterectomy, or 3) both. Analyses performed included Kaplan-Meier, incident rate ratios, and Cox proportional hazard ratios.

RESULTS

One thousand four hundred forty-three eligible women were identified. One thousand two hundred one had complex (n=164 no progestin) and 242 had atypical (n=62 no progestin) hyperplasia. During follow-up, a median of 5.3 years (range 8 weeks to 20.8 years), 71 women were diagnosed with endometrial carcinoma (35 complex, 36 atypia) and 323 underwent hysterectomy (216 complex, 107 atypia). Among women with complex and atypical hyperplasia, rates of endometrial carcinoma among progestin users were 3.6 and 20.5 per 1,000 woman-years, respectively (compared with women who did not use progestin, 10.8 and 101.4). Among women with complex and atypical hyperplasia, rates of hysterectomy among progestin users were 23.3 and 61.4 per 1,000 woman-years, respectively (compared with women who did not use progestin, 55.1 and 297.3).

CONCLUSION

Endometrial carcinoma risk is diminished approximately threefold to fivefold in women diagnosed with complex or atypical endometrial hyperplasia and dispensed progestin; hysterectomy risk is also decreased.

LEVEL OF EVIDENCE

II.

Detection of chromosomal anomalies in endometrial atypical hyperplasia and carcinoma by using fluorescence in situ hybridization

BACKGROUND

Endometrial cancer is the most common pelvic gynecological malignancy. The diagnosis of well-differentiated endometrial adenocarcinoma, atypical hyperplasia, and hyperplasia is often challenging. The authors sought to investigate the utility of chromosomal anomalies for the detection of endometrial hyperplasia and carcinoma using multitarget fluorescence in situ hybridization (FISH).

METHODS

Samples were collected by endometrial Tao brush and processed by liquid-based cytological preparation protocol from consecutive cases to include 50 benign, 50 hyperplasia without atypia, 47 atypical hyperplasia, and 53 endometrial cancers. Each was hybridized using fluorescence-labeled DNA probes to chromosomes 1, 8, and 10. The FISH signals were enumerated in 100 cells per case, and the chromosomal anomalies were correlated with pathologic findings, including histologic diagnoses on matched endometrial tissue samples.

RESULTS

Numeric chromosomal anomalies were found in 0% (0 of 50) of benign, 20% (10 of 50) of hyperplasia, 74% (35 of 47) of atypical hyperplasia, and 87% (46 of 53) of carcinoma specimens. The mean percentage of cells with chromosomal changes was 55% in cancer specimens, which was significantly higher than that in hyperplasia without atypia (13%, P < .0001) and atypical hyperplasia (32%, P = .003). The most frequent chromosomal anomaly was gain of chromosome 1. FISH anomalies had an overall sensitivity of 81% and specificity of 90% for the detection of atypical hyperplasia and/or endometrial carcinoma. There was no association with grade of endometrial carcinoma.

CONCLUSIONS

Multitarget FISH appears to be useful for the differential diagnosis of hyperplasia, atypical hyperplasia, and endometrial adenocarcinoma, with a high level of sensitivity and specificity. It is also a potential tool for the early detection of neoplastic cells in endometrial cytology specimens. Endometrial hyperplasia with FISH-detected chromosomal anomalies may represent a clinically significant subset of cases that warrant close clinical follow-up.