Reproducibility of grading systems for endometrial endometrioid carcinoma and their relation with pathologic prognostic parameters

The Significance of International Federation of Gynecology and Obstetrics Grading in Microsatellite Instability-High and POLE-Mutant Endometrioid Endometrial Carcinoma

With the advancement of diagnostic molecular technology and the molecular classification of endometrial endometrioid carcinoma (EEC), it remains to be seen whether conventional International Federation of Gynecology and Obstetrics (FIGO) grading retains clinical significance in certain molecular subtypes of EECs. In this study, we explored the clinical significance of FIGO grading in microsatellite instability-high (MSI-H) and POLE-mutant EECs. A total of 162 cases of MSI-H EECs and 50 cases of POLE-mutant EECs were included in the analysis. Significant differences in tumor mutation burden (TMB), progression-free survival, and disease-specific survival were seen between the MSI-H and POLE-mutant cohorts. Within the MSI-H cohort, there were statistically significant differences in TMB and stage at presentation across FIGO grades, but not survival. Within the POLE-mutant cohort, there was significantly greater TMB with increasing FIGO grade, but there were no significant differences in stage or survival. In both the MSI-H and POLE-mutant cohorts, log-rank survival analysis showed no statistically significant difference in progression-free and disease-specific survival across FIGO grades. Similar findings were also seen when a binary grading system was utilized. Since FIGO grade was not associated with survival, we conclude that the intrinsic biology of these tumors, characterized by their molecular profile, may override the significance of FIGO grading.

Identification of histological features of endometrioid adenocarcinoma based on amide proton transfer-weighted imaging and multimodel diffusion-weighted imaging

BACKGROUND

Noninvasive identification of the histological features of endometrioid adenocarcinoma is necessary. This study aimed to investigate whether amide proton transfer-weighted imaging (APTWI) and multimodel (monoexponential, biexponential, and stretched exponential) diffusion-weighted imaging (DWI) could predict the histological grade of endometrial adenocarcinoma (EA). In addition, we analyzed the correlation between each parameter and the Ki-67 index.

METHODS

A total of 90 EA patients who received pelvic magnetic resonance imaging (MRI) were enrolled. The magnetization transfer ratio asymmetry [MTRasym (3.5 ppm)], apparent diffusion coefficient (ADC), diffusion coefficient (D), pseudo-diffusion coefficient (D*), perfusion fraction (f), distributed diffusion coefficient (DDC), and water molecular diffusion heterogeneity index (α) were measured and compared. Correlation coefficients between each parameter and histological grade and the Ki-67 index were calculated. Statistical methods included the independent samples t test, Spearman's correlation, and logistic regression.

RESULTS

MTRasym (3.5 ppm) [(3.72%±0.31%) vs. (3.27%±0.48%)], f [(3.15%±0.36%) vs. (2.69%±0.83%)], and α [(0.89±0.05) vs. (0.81±0.09)] were higher and ADC [(0.82±0.08) vs. (0.89±0.10) ×10^-3 mm²/s], D [(0.67±0.09) vs. (0.81±0.11) ×10^-3 mm²/s], and DDC [(1.04±0.09) vs. (1.13±0.13) ×10^-3 mm²/s] were lower in high-grade EA than in low-grade EA (P<0.05). MTRasym (3.5 ppm) and D were independent predictors for the histological grade of EA. The combination of MTRasym (3.5 ppm) and D were better able to identify high- and low-grade EA than was each parameter. MTRasym (3.5 ppm) and α were moderately and weakly positively correlated, respectively, with histological grade and the Ki-67 index (r=0.528, r=0.514, r=0.395, and r=0.367; P<0.05). D was moderately negatively correlated with histological grade and the Ki-67 index (r=-0.540 and r=-0.529; P<0.05). DDC was weakly and moderately negatively correlated with histological grade and the Ki-67 index, respectively (r=-0.473 and r=-0.515; P<0.05). ADC was weakly negatively correlated with histological grade and the Ki-67 index (r=-0.417 and r=-0.427; P<0.05). f was weakly positively correlated with histological grade and the Ki-67 index (r=0.294 and r=0.355; P<0.05).

CONCLUSIONS

Our study found that both multimodel DWI and APTWI could be used to estimate the histological grade and Ki-67 index of EA, and the combination of high MTRasym (3.5 ppm) and low D may be an effective imaging marker for predicting the grade of EA.

Amide Proton Transfer-Weighted Imaging and Multiple Models Diffusion-Weighted Imaging Facilitates Preoperative Risk Stratification of Early-Stage Endometrial Carcinoma

BACKGROUND

Endometrial carcinoma (EC) risk stratification is generally based on histological assessment. It would be beneficial to perform risk stratification noninvasively by MRI.

PURPOSE

To investigate the application of amide proton transfer-weighted imaging (APTWI), monoexponential, biexponential, and stretched exponential intravoxel incoherent motion (IVIM), and diffusion kurtosis imaging (DKI) for the evaluation of risk stratification in early-stage EC.

STUDY TYPE

Prospective.

POPULATION

Eighty patients with early-stage EC (47 classified as low risk, 20 as medium risk, and 13 as high risk by histological grade and International Federation of Gynecology and Obstetrics stage).

FIELD STRENGTH/SEQUENCE

T1-weighted imaging, T2-weighted imaging, IVIM, APTWI, and DKI MRI at 3 T.

ASSESSMENT

The magnetization transfer ratio asymmetry (MTRasym [3.5 ppm]), apparent diffusion coefficient (ADC), diffusion coefficient (D), pseudo diffusion coefficient (D*), perfusion fraction (f), distributed diffusion coefficient (DDC), water molecular diffusion heterogeneity index (α), mean kurtosis (MK), and mean diffusivity (MD) were calculated and compared between low-risk and non-low-risk groups.

STATISTICAL TESTS

Individual sample t test, analysis of variance, and logistic regression. A P-value <0.05 was considered statistically significant.

RESULTS

The α, ADC, D, DDC, and MD were significantly higher and the f, MK, and MTRasym (3.5 ppm) were significantly lower in the low-risk group than in the non-low-risk group. The difference in D* between the two groups was not significant (P = 0.289). MTRasym (3.5 ppm), D, and MK were independent predictors of risk stratification. The combination of these three parameters was better able to identify low- and non-low-risk groups than each individual parameter.

DATA CONCLUSION

The IVIM, DKI, and APTWI parameters have potential as imaging markers for risk stratification in early-stage EC.

LEVEL OF EVIDENCE

2 TECHNICAL EFFICACY: Stage 3.

Assessment of Preoperative Endometrial Histopathological Sampling as a Predictor of Final Surgical Pathology in Endometrial Cancer

OBJECTIVE

 To evaluate the agreement between the histopathological diagnoses of preoperative endometrial samples and surgical specimens and correlate the agreement between the diagnoses with the impact on surgical management and the survival of patients with endometrial adenocarcinomas.

METHODS

 Sixty-two patients treated for endometrial cancer at a university hospital from 2002 to 2011 were retrospectively evaluated. The histopathological findings of preoperative endometrial samples and of surgical specimens were analyzed. The patients were subjected to hysterectomy as well as adjuvant treatment, if necessary, and clinical follow-up, according to the institutional protocol. Lesions were classified as endometrioid tumor (type 1) grades 1, 2, or 3 or non-endometrioid carcinoma (type 2).

RESULTS

 The agreement between the histopathological diagnoses based on preoperative endometrial samples and surgical specimens was fair (Kappa: 0.40; p < 0.001). However, the agreement was very significant for tumor type and grade, in which a higher concordance occurred at a higher grade. The percentage of patients with lymph nodes affected was 19.2%. Although most patients presenting with disease remission or cure were in the early stages (90.5%), there were no significant differences between those patients who had a misdiagnosis (11/16; 68.8%) and those who had a correct diagnosis (25/33; 75.8%) based on preoperative endometrial sampling (p = 0.605).

CONCLUSION

 Our findings corroborate the literature and confirm the under staging of preoperative endometrial samples based on histopathological assessment, especially for lower grade endometrial tumors. We suggest that the preoperative diagnosis should be complemented with other methods to better plan the surgical management strategy.

A Modern Approach to Endometrial Carcinoma: Will Molecular Classification Improve Precision Medicine in the Future?

Endometrial cancer has been histologically classified as either an estrogen-dependent cancer with a favorable outcome or an estrogen-independent cancer with a worse prognosis. These parameters, along with the clinical attributions, have been the basis for risk stratification. Recent molecular and histopathological findings have suggested a more complex approach to risk stratification. Findings from the Cancer Genome Atlas Research Network established four distinctive genomic groups: ultramutated, hypermutated, copy-number low and copy-number high prognostic subtypes. Subsequently, more molecular and histopathologic classifiers were evaluated for their prognostic and predictive value. The impact of molecular classification is evident and will be recognized by the upcoming WHO classification. Further research is needed to give rise to a new era of molecular-based endometrial carcinoma patient care.

Prognosis Trend of Grade 2 Endometrioid Endometrial Carcinoma: Toward Grade 1 or 3?

Although the prognostic significance of grade in endometrial cancer is well known, grade 2 cases have not been evaluated separately in most of the previous studies. In this study, we aim to investigate whether the oncologic outcomes of grade 2 endometrioid endometrial carcinomas trend towards grade 1 or 3 tumors. Patients' records and pathological reports were reviewed retrospectively and eligible patients with endometrioid endometrial carcinoma were determined and distributed into 3 groups according to their 1988 International Federation of Gynecology and Obstetrics (FIGO) grade. Groups' characteristics and oncologic outcomes were compared. Differences between grades were tested with z-test and adjusted by Bonferroni method. Kaplan-Meier method was performed for the survival analysis. In total, 776 patients of endometrioid endometrial carcinoma were included in this study. Mean follow-up time was 52 ± 14 months. Patients' mean age was 56.3 ± 10.8 years. Even though grade 2 endometrioid endometrial carcinomas were different from both grade 1 and 3 in terms of the pathological features, survival analyses demonstrated that their oncologic outcomes trended towards grade 1. The grade was determined as an independent prognostic factor for overall survival (OS). The interobserver reproducibility will be improved among pathologists by combining FIGO grade 1 and 2 endometrioid endometrial carcinomas, while prognosis prediction is not likely to be affected.

High-Grade Endometrial Carcinomas: Classification with Molecular Insights

This article provides an overview of the current diagnosis of endometrial carcinoma subtypes and provides updates, including the most recent molecular findings from The Cancer Genome Atlas and others. Interpretation of relevant immunohistochemistry and critical diagnostic differential diagnosis with pitfalls are discussed.

Endometrial Carcinoma Diagnosis: Use of FIGO Grading and Genomic Subcategories in Clinical Practice: Recommendations of the International Society of Gynecological Pathologists

In this review, we sought to address 2 important issues in the diagnosis of endometrial carcinoma: how to grade endometrial endometrioid carcinomas and how to incorporate the 4 genomic subcategories of endometrial carcinoma, as identified through The Cancer Genome Atlas, into clinical practice. The current International Federation of Gynecology and Obstetrics grading scheme provides prognostic information that can be used to guide the extent of surgery and use of adjuvant chemotherapy or radiation therapy. We recommend moving toward a binary scheme to grade endometrial endometrioid carcinomas by considering International Federation of Gynecology and Obstetrics defined grades 1 and 2 tumors as "low grade" and grade 3 tumors as "high grade." The current evidence base does not support the use of a 3-tiered grading system, although this is considered standard by International Federation of Gynecology and Obstetrics, the American College of Obstetricians and Gynecologists, and the College of American Pathologists. As for the 4 genomic subtypes of endometrial carcinoma (copy number low/p53 wild-type, copy number high/p53 abnormal, polymerase E mutant, and mismatch repair deficient), which only recently have been identified, there is accumulating evidence showing these categories can be reproducibly diagnosed and accurately assessed based on biopsy/curettage specimens as well as hysterectomy specimens. Furthermore, this subclassification system can be adapted for current clinical practice and is of prognostic significance independent of conventional variables used for risk assessment in patients with endometrial carcinoma (eg, stage). It is too soon to recommend the routine use of genomic classification in this setting; however, with further evidence, this system may become the basis for the subclassification of all endometrial carcinomas, supplanting (partially or completely) histotype, and grade. These recommendations were developed from the International Society of Gynecological Pathologists Endometrial Carcinoma project.

Myoferlin Expression and Its Correlation with FIGO Histologic Grading in Early-Stage Endometrioid Carcinoma

Background

For endometrioid carcinoma patients, International Federation of Gynecologists and Obstetricians (FIGO) histologic grading is very important for identifying the appropriate treatment method. However, the interobserver discrepancy with this three-tiered grading system is a serious potential problem. In this study, we used immunohistochemistry to analyze the relationship between FIGO histologic grading score and myoferlin expression.

Methods

We studied the endometrioid carcinoma tissues of 60 patients from Gyeongsang National University Hospital between January 2002 and December 2009. Immunohistochemical analysis of myoferlin was performed on tissue microarray blocks from surgical specimens.

Results

Myoferlin expression was observed in 58 of 60 patients. Moderate and strong myoferlin expression was observed in low-grade endometrioid carcinoma, while there was a tendency toward loss of myoferlin expression in high-grade endometrioid carcinoma (p<.001).

Conclusions

Our study revealed that myoferlin loss is significantly correlated with high FIGO grade of endometrioid carcinoma.

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.

Comparative study of different histologic classifications in the degree of differentiation in endometrial adenocarcinoma

PURPOSE

To evaluate the concordance among the available histologic classifications for endometrial adenocarcinoma using interobserver and intraobserver agreement as well as the association of tumor histologic degree in the above mentioned classifications with cellular proliferation measured by Ki-67.

METHODS

Seventy women who underwent surgical treatment of endometrial adenocarcinoma with histologic confirmation of endometrioid type were included in the study. Two experienced pathologists randomly analyzed the slides in 3 distinct timeframes with a maximum of 25 slides/timeframe. Tumor slides were classified according to the degree of differentiation using 4 different classifications: International Federation of Gynecology and Obstetrics (FIGO), modified FIGO, Lax, and Alkushi.

RESULTS

Intraobserver agreement was reasonable for classification of FIGO (k 0.469 and 0.538), very good for modified FIGO (k 0.661 and 0.768), moderate for Lax classification (k 0.496 and 0.466), and moderate/good for Alkushi classification (k 0.528 and 0.736). Interobserver concordance was regular for FIGO classification (k = 0.271 and 0.343), good/moderate for modified FIGO classification (k = 0.661 and 0.522, respectively), regular/moderate for Lax classification (k = 0.258 and 0.465, respectively), and regular for Alkushi classification (k = 0.283 and 0.402).

CONCLUSIONS

The prognostic value of histologic grading in endometrial carcinoma and its importance for a successful therapeutic plan have been documented repeatedly, but the best grading system, in terms of prognostication, reproducibility, ease of use, and universality (e.g., applicability to all tumor cell types), has not been unequivocally defined.

Molecular staging of gynecological cancer: What is the future?

The purpose of cancer staging is to classify cancers into prognostic groups and to allow for comparison of treatment results and survival between patients and institutions. Staging for gynecologic cancers is based on extent of disease and metastasis, which was historically determined by physical examination and is now based on surgical and histologic examination of tumor specimens. Although the extent of disease is currently considered the most important predictor of recurrence and survival, current staging does not include molecular features that are associated with tumor aggressiveness, response to therapy, and prognosis. This review focuses on genomic and proteomic features of gynecologic cancers and the future of biomarkers in staging classification.

Prognostic biomarkers in endometrial and ovarian carcinoma

This article reviews the main prognostic and predictive biomarkers of endometrial (EC) and ovarian carcinoma (OC). In EC, prognosis still relies on conventional pathological features such as histological type and grade, as well as myometrial or lymphovascular space invasion. Estrogen receptor, p53, Ki-67, and ploidy analysis are the most promising biomarkers among a long list of molecules that have been proposed. Also, a number of putative predictive biomarkers have been proposed in molecular targeted therapy. In OC, prognosis is predominantly dependent on disease stage at diagnosis and the extent of residual disease at primary operation. Diagnostic markers which aid in establishing histological type in OC are available. However, not a single universally accepted predictive or prognostic marker exists to date. Targeted therapy has been growingly focused at in recent years, in view of the frequent development of chemoresistance at recurrent disease. The present review emphasizes the crucial role of correct pathological classification and stringent selection criteria of the material studied as basis for any evaluation of biological markers. It further emphasizes the promise of targeted therapy in EC and OC, while simultaneously highlighting the difficulties remaining before this can become standard of care.

Problematic issues in the staging of endometrial, cervical and vulval carcinomas

The International Federation of Gynecology and Obstetrics (FIGO) staging of tumours of the uterine corpus, cervix and vulva was revised in 2009. The greatest impact of the revised staging was on carcinomas of the uterine corpus. Uterine sarcomas are now staged separately. Changes to the staging system for vulvar carcinomas largely reflect the significance of lymph node status. Only minor amendments have been introduced for cervical carcinomas, which remain the only gynaecological tumours to be staged clinically. These revisions, based on recent evidence, require careful, more detailed assessment of several histological parameters at each anatomical site. The present review deals with the evidence and rationale underpinning the revisions, and includes practical guidance on tumour staging. This covers the assessment and measurement of myoinvasion and evaluation of cervical, parametrial, serosal and vaginal involvement in carcinomas of the uterine corpus; the identification and accurate measurement of stromal invasion in cervical and vulvar carcinomas; the assessment of unusual variants of carcinoma at each of these sites; and the assessment of lymph node involvement.

A triage assessment strategy for the management of women with endometrial cancer

OBJECTIVE

This study examined a risk-factor-based assignment to either a subspecialist or a general gynaecologist for the management of women with endometrial cancer.

METHODS

At diagnosis, all women with a diagnosis of endometrial cancer in four community hospitals were referred to a central cancer centre and stratified into low- and high-risk groups. Risk stratification was based primarily on central pathology review, with low-risk disease defined as grade 1, clinical stage 1. Women with low-risk disease were triaged back to the referring gynaecologist for surgery. Women with high-risk disease were managed at the cancer centre. The main outcome measures included risk status and pathology review, treatment and treatment location, and acceptability to patients and gynaecologists.

RESULTS

Seventy-three women participated in this pilot study between November 2009 and 2010. Risk stratification was performed in all women: 37 were classified as high risk and 36 as low risk. Ninety-seven percent of women with high-risk disease were managed at the cancer centre, and 83% of these women underwent surgical staging compared with 8% for women with low-risk disease. This approach was acceptable to both patients and gynaecologists.

CONCLUSION

This structured pattern of care for women with endometrial cancer resulted in a shift in management, with more women managed in accordance with oncologic guidelines, meaning that women at high risk for metastases had a lymphadenectomy performed.

Endometrial carcinoma: controversies in histopathological assessment of grade and tumour cell type

Histopathological assessment of tumour grade and cell type is central to the management of endometrial carcinoma, guiding the extent of surgery and the use of adjuvant radiation therapy and chemotherapy. Endometrioid carcinomas are usually low grade but high-grade examples are encountered, and they have a significantly worse prognosis, similar to that of high-grade subtypes such as serous and clear cell carcinoma. This article reviews the various grading systems that have been proposed for use with endometrioid endometrial carcinoma, and discusses the recent progress in cell type assignment, including the use of immunohistochemistry as a diagnostic adjunct.

Critical study of observation of the sternal end of the right 4th rib

Studies of the method of estimating age at death by the 4th rib exclusively concerned the phase method without fundamentally challenging the method as such. The present study analyzed observation of the variables on which the Işcan method is based. Ten observers made two assessments of the stage of pit depth, pit shape, rim and wall configurations of 59 right 4th ribs harvested from males (mean age: 49 years; range: 47-94 years). Observation showed poor reproducibility and repeatability for all three variables (Wilcoxon test, kappa-coefficient). Analysis of problem ribs revealed difficulty in measuring and imprecision in describing pit depth and failure to take account of continual aging for the other two variables. Despite these results, Işcan's variables provide objective information on age at death. It is recommended that the method be improved by better description of the variables and use of multivariate statistical analysis.