Non-endometrioid carcinomas of the uterine corpus: a review of their pathology with emphasis on recent advances and problematic aspects

EPPK1 as a Prognostic Biomarker in Type I Endometrial Cancer and Its Correlation with Immune Infiltration

Purpose

Approximately 20% of patients with type I endometrial cancer (EC) of the uterus experience recurrence and metastasis. However, existing data do not provide sufficient evidence for the utility of protein levels as prognostic biomarkers in type I EC. This study aims to determine whether epiplakin1 (EPPK1) and progesterone receptor (PR) play a role in the recurrence and metastasis of type I EC.

Methods

Following the Reporting Recommendations for Tumor Marker Prognostic Studies (REMARK) for assessing the quality of biomarker research results, a retrospective analysis was conducted on clinical information and tissue samples of type I EC patients. Protein expression data and clinical data for type I EC were downloaded from The Cancer Proteome Atlas (TCPA) database. We utilized the Kaplan-Meier (K-M) method and Cox proportional hazards regression analyses to evaluate whether epiplakin1 (EPPK1), progesterone receptor (PR) and certain clinical parameters can serve as independent prognostic factors. The Immune Cell Abundance Identifier (ImmuCellAI) and Cancer Immunome Atlas (TCIA) were employed to predict responses to immunotherapy. Immunohistochemistry was carried out to assess the expression of EPPK1 in type I EC.

Results

Type I EC patients with high EPPK1 and low PR expression had higher International Federation of Gynecology and Obstetrics (FIGO) stage, recurrence, and metastasis rates. Furthermore, EPPK1 was identified as an independent prognostic factor, and low expression of EPPK1 was predominantly observed in the POLE ultramutated (POLEmut) group, indicating a favorable prognosis. Additionally, the high EPPK1 expression group had a lower Immune Prognostic Score (IPS), suggesting that the high-expression group may not benefit from immune checkpoint inhibitors.

Conclusion

High expression of EPPK1 is an independent prognostic factor in type I EC patients with low PR expression. It can identify a subgroup of patients at high risk of recurrence. A more aggressive treatment approach is recommended for these patients.

Estrogen Receptor (ER) and Progesterone Receptor (PgR) Expression in Endometrial Cancer-An Immunohistochemical Assessment

Endometrial cancer (EC) is one of the most common types of cancer in Poland and worldwide. Many risk factors lead to the pathogenesis of this disease, such as lifestyle choices, BMI, the medicines used in breast cancer therapy, and Lynch syndrome. EC cells show the expression of estrogen receptors (ERs) and progesterone receptors (PgR). These receptors occur in multiple isoforms and have a significant influence on the operation of cells. The loss of ER and PgR expression is associated with a poor prognosis. We assessed tissue slides that were obtained from 103 women with EC diagnoses of various grades, stages, and histological types. In this study, we used computer image analyses to increase the objectivity of the assessment. We proved that, in the tissue of patients with high-grade (G3) EC, the expression of PgR is significantly lower than that in the tissues of patients with low-grade EC. We also observed that PgR is significantly expressed in EC with a low FIGO stage and in the endometroid type of EC (which rarely becomes malignant compared to serous type). The expression of ERb1 was lower in patients with EC at the IV FIGO stage than in patients with stage III EC. These findings confirm that the loss of ER and PgR expression is connected with a poor prognosis.

A predictive model for lymph node metastasis using tumor location in presumed early-stage endometrioid endometrial cancer patients

OBJECTIVE

The aim of this study was to identify high- and low-risk subgroups of patients with lymph node (LN) metastasis in presumed early-stage endometrioid endometrial cancer (EC) patients.

METHODS

Clinicopathologic data of presumed early-stage endometrioid EC patients (n=361) treated with lymphadenectomy between March 2000 and July 2022 were analyzed. None of the patient had definite evidence of LN metastasis in a preoperative magnetic resonance imaging (MRI). A received operating characteristic curve analysis was conducted to define the sensitivity and specificity for the combined preoperative risk factors for LN metastasis, which was determined by multivariate analysis.

RESULTS

Nineteen patients (5.3%) had LN metastasis. Multivariate analysis identified cervical stromal invasion on MRI (odds ratio [OR]=4.386; 95% confidence interval [CI]=1.020-18.852; p=0.047), cornual location of tumor on MRI (OR=36.208; 95% CI=7.902-165.913; p<0.001), and lower uterine segment/isthmic location of tumor on MRI (OR=8.454; 95% CI=1.567-45.610; p=0.013) as independent prognostic factors associated with LN metastasis. Patients were categorized into low- and high-risk groups according to risk criteria. Significant differences in the rates of LN metastasis were observed between the two groups (0.4% vs. 22.2%, p<0.001).

CONCLUSION

Approximately 95% of presumed early-stage endometrioid EC patients did not have LN metastasis. A model using tumor location was significantly correlated with the risk of LN metastasis. Even in presumed early-stage endometrioid EC patients, therefore, tumor location should be investigated to determine whether to perform LN assessment.

Metastatic Cholangiocarcinoma to the Uterus Morphologically Imitating Primary Intestinal-type Endometrioid Adenocarcinoma

Cholangiocarcinoma is an uncommon and aggressive malignancy of intrahepatic and extrahepatic bile ducts. We present a case of a 37-year-old woman with cholangiocarcinoma metastatic to the endometrium that mimicked a primary endometrial adenocarcinoma at resection. The patient is status-post orthotopic liver transplant for cholangiocarcinoma. She presented for evaluation of a clear, odorless vaginal discharge of 6 months' duration. Endometrial biopsy demonstrated an adenocarcinoma with mucinous features similar to primary endometrial adenocarcinoma, but with an immunophenotype consistent with metastatic cholangiocarcinoma. Subsequent hysterectomy demonstrated complete replacement of the native endometrium, a presentation that represents, to our knowledge, the first such reported in the literature. Overall, extragenital metastatic disease to the uterine corpus is rare and involvement of the endometrium even less common. Metastatic cholangiocarcinoma represents a small subset of these metastases to the uterus.

Surgical Treatment Outcomes of Gynecologic Cancer in Older Patients: A Retrospective Study

This study aimed to evaluate oncologic characteristics and surgical outcomes in older patients with gynecologic cancers. This retrospective study included patients aged ≥65 years who were diagnosed with gynecologic cancers and underwent surgical treatment between 2005 and 2020. We reviewed the medical records for age at diagnosis, body mass index, American Society of Anesthesiologists score, comorbidities, postoperative complications, cancer stage, histologic type, surgical treatment, postoperative outcome, and survival rate. Data were compared between groups according to the age at the time of diagnosis: <75 years (young-old) and ≥75 years (old-old). In total, 131 patients were identified: 53 (40.5%) with ovarian or primary peritoneal cancer (OC), 44 (33.6%) with endometrial cancer (EC), 30 (22.9%) with cervical cancer, and 4 (3.1%) with leiomyosarcoma. The patients’ mean age was 70 (range, 65–83) years; 106 (80.9%) were young-old and 25 (19.1%) were old-old. Postoperative complications occurred in 19 (14.5%) patients. Four patients died within six months after surgery, and three died because of disease progression. There was no difference in the survival rates between the two groups among those with OC and EC. Older patients with gynecologic cancers showed good surgical outcomes and tolerable postoperative complications. Therefore, we can safely offer surgical treatment to older patients.

Stage I Clear Cell and Serous Uterine Carcinoma: What Is the Right Adjuvant Therapy?

This single-center study aimed to retrospectively evaluate the survival outcomes of patients with FIGO stage I clear cell and serous uterine carcinoma according to the type of adjuvant treatment received. The data were collected between 2003 and 2020 and only patients with stage I clear cell or serous uterine carcinoma treated with primary surgery were included. These were classified into three groups: No treatment or brachytherapy only (G1), radiotherapy +/- brachytherapy (G2), chemotherapy +/- radiotherapy +/- brachytherapy (G3). In total, we included 52 patients: 18 patients in G1, 16 in G2, and 18 in G3. Patients in the G3 group presented with poorer prognostic factors: 83.3% had serous histology, 27.8% LVSI, and 27.8% were FIGO stage IB. Patients treated with adjuvant radiotherapy showed an improved 5-year overall survival (OS) (p = 0.02) and a trend towards an enhanced 5-year progression-free survival (PFS) (p = 0.056). In contrast, OS (p = 0.97) and PFS (p = 0.84) in the chemotherapy group with poorer prognostic factors, were similar with increased toxicity (83.3%). Radiotherapy is associated with improved 5-year OS and tends to improve 5-year PFS in women with stage I clear cell and serous uterine carcinoma. Additional chemotherapy should be cautiously considered in serous carcinoma cases presenting poor histological prognostic factors.

Variants of in situ carcinoma of the endometrium: Clear cell and gastrointestinal types, with a review of the literature

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In-situ lesions of endometrial carcinomas clear cell and intestinal types are not a well-recognized entity, although these exist.

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We’re describing three such lesions.

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We also discussed available English literature on this topic.

Two precursor lesions are commonly associated with endometrial carcinoma. Atypical endometrial hyperplasia/endometrial intraepithelial neoplasia is a known precursor lesion of endometrial endometrioid carcinoma, while endometrial intraepithelial carcinoma, is a recognized precursor lesion of endometrial high-grade serous carcinoma. Other than these two recognized entities, other rare precursor lesions for endometrial carcinoma do exist, although reported cases are relatively few and not universally recognized. This therefore poses diagnostic challenges in clinical practice. Here, we describe a series of rare precursor lesions of the endometrium identified at our institution, including clear cell and gastrointestinal variants, their morphologic and immunohistochemical characteristics, and review current literature regarding these variants. The information provided may guide the proper diagnosis and ultimately lead to effective clinical management in every-day practice.

Endometrial cancer prognosis in women with endometriosis and adenomyosis: A retrospective nationwide cohort study of 40 840 women

We aim to compare endometrial cancer survival in women with or without histological proven endometriosis or adenomyosis. We identified all women with endometrial cancer between 1990 and 2015 from the Netherlands Cancer Registry (NCR). Data were linked to the Dutch pathology database (PALGA) to select all women with histological proven endometriosis/adenomyosis. Overall survival was compared between women with endometrial cancer with or without endometriosis/adenomyosis. We used multivariable Cox proportional hazard analysis to estimate hazard ratios (HRs). We included 1701 women with endometrial cancer and endometriosis/adenomyosis, of whom 1236 (72.7%) women had adenomyosis, 320 (18.8%) had endometriosis and 145 (8.5%) had both. We compared these women to 39 139 women with endometrial cancer without endometriosis/adenomyosis. Women in the combined endometriosis/adenomyosis cohort were younger at endometrial cancer diagnosis, had earlier disease stage, more often had endometrioid endometrial cancer and low grade tumors. The 5-year survival rate in the combined endometriosis/adenomyosis cohort was 84.8% (95% CI 84.6-88.1) and 71.6% (95% CI 71.1-72.0) in the nonendometriosis/adenomyosis cohort. Univariable analysis resulted in a crude HR of 0.63 (95% CI 0.59-0.69). Significant confounding factors were age, stage, cancer subtype, histological grading, surgery and chemotherapy rate. Correction for these confounders resulted in a HR of 0.98 (95% CI 0.90-1.06). Including endometriosis/adenomyosis status as a categorical factor resulted in similar HRs. In conclusion, women with endometrial cancer and histologically proven endometriosis/adenomyosis have a better overall survival when compared to women with endometrial cancer without endometriosis/adenomyosis. This better survival was correlated to stage, grade, age and histological subtype, but not to the presence of endometriosis/adenomyosis.

Systematic Lymphadenectomy and Oncological Outcomes of Women With Apparent Early-Stage Clear Cell Carcinoma of the Endometrium: A Multi-Institutional Cohort Study

Objective

The survival value of systematic lymphadenectomy for endometrial cancer is ambiguous and controversial. The current study aimed to evaluate the long-term survival role of combined pelvic and para-aortic lymphadenectomy in patients with presumed early-stage clear cell carcinoma of the endometrium.

Methods

Patients in three Chinese teaching hospitals who presented between 2012 and 2017 with apparent early-stage clear cell carcinoma of the endometrium and underwent surgical staging were selected. Patients who did and did not undergo systematic lymphadenectomy were identified and clinicopathological characteristics were compared. Disease-free survival and overall survival were evaluated following the generation of the Kaplan-Meier curves and the comparison using the log-rank test. A Cox proportional hazards model was employed to control for confounders.

Results

A total of 244 patients underwent systematic lymphadenectomy and 89 did not receive lymph node dissection. The demographic and baseline data were comparable between the two groups. The rate of disease-free survival at 5 years was 64.10% in patients who underwent systematic lymphadenectomy and 45.05% in patients who did not undergo lymphadenectomy. Patients who underwent systematic lymphadenectomy had better disease-free survival than those who did not receive lymphadenectomy (HR, 0.54. 95% CI, 0.38-0.76. P=0.000). The rate of 5-year overall survival was 68.87% in the lymphadenectomy group and 53.33% in patients who did not undergo systematic lymphadenectomy. Systematic lymphadenectomy was also associated with improved 5-year overall survival for women with presumed early-stage clear cell carcinoma of the endometrium (HR, 0.58. 95% CI, 0.39-0.85. P=0.005). After adjusting for confounders, systematic lymphadenectomy was still independently associated with improved disease-free survival and overall survival.

Conclusion

Patients with apparent early-stage clear cell carcinoma of the endometrium who underwent systematic lymphadenectomy had better long-term survival than those who did not undergo systematic lymphadenectomy.

Endometrial Cancer Incidence in Endometriosis and Adenomyosis

Women with histologically proven endometriosis/adenomyosis have an increased risk of ovarian cancer. Small studies show conflicting results on the endometrial cancer risk in women with endometriosis/adenomyosis. Therefore, we assessed the incidence of endometrial cancer in women with histologically proven endometriosis or adenomyosis. We performed a population-based retrospective cohort study of 129,862 women with histologically proven endometriosis/adenomyosis, matched with 132,700 women with a nevus selected from the Dutch pathology registry between 1990 and 2015. Histology results for endometrial cancer were retrieved. Crude and age-adjusted odds ratios for endometrial cancer were estimated. In the endometriosis/adenomyosis group, 1827 (1.4%) women had a histological report on endometrial cancer, and in the nevus group, 771 (0.6%) women. The age-adjusted OR for endometrial cancer was 2.58 (95%CI 2.37-2.81). After excluding the first year of follow-up, the age-adjusted OR was 0.76 (95%CI 0.63-0.92), indicating that endometrial cancer is most often found at time of histological diagnosis of endometriosis/adenomyosis. In around 20% of the endometrial cancer cases, the endometrial cancer was not recognized until after hysterectomy. Of these women, 35% had no prior (micro)curettage or biopsy. This study shows an increased incidence of endometrial cancer in women with histologically proven endometriosis and adenomyosis.

Treatment outcomes and complications in FIGO stage IIIC and IVB endometrioid endometrial cancer patients presenting as nodal spreads following systematic lymphadenectomy and adjuvant therapy

OBJECTIVE

To evaluate the treatment outcomes and complications of patients with FIGO stage IIIC and IVB endometrioid endometrial cancer (EC) presenting primarily as nodal spreads following systematic lymphadenectomy and adjuvant therapy.

MATERIAL AND METHODS

Forty-four FIGO stage IIIC and IVB endometrioid EC patients between July 2003 and March 2020 received staging procedures including systematic lymphadenectomy. The survival outcomes and late treatment-related complications were compared between adjuvant chemoradiation-based group and chemotherapy-based group.

RESULTS

Of the 44 patients, 16 (36.4%) had stage IIIC1, 26 (59.1%) had stage IIIC2, and 2 (4.5%) had stage IVB disease. The median follow-up time was 54 months (range, 10-185 months). There was no statistical difference in mortality between the microscopic and macroscopic nodal groups (6.2% vs 4.3%, p > 0.999). Eleven patients (25.0%) and 33 patients (75.0%) received adjuvant chemoradiation and chemotherapy, respectively. The 5-year disease-free and overall survival rates were not different between the two groups (disease-free survival, 81.8% vs 82.1%, p = 0.743; overall survival, 90.9% vs 95.8%, p = 0.537). The incidence rates of grade 2 lymphedema (36.4% vs 9.1%, p = 0.032) and grade 2/3 gastrointestinal complications (36.4% vs 0.0%, p < 0.001) were higher in the chemoradiation-based group than those in the chemotherapy-based group.

CONCLUSIONS

Systematic lymphadenectomy and adjuvant chemotherapy might be the preferred treatment for FIGO stage IIIC and IVB endometrioid EC patients presenting as nodal spreads given that no difference in patient survival was found, but a higher incidence of treatment-related complications was observed in the chemoradiation-based group.

Uterine serous carcinoma: key advances and novel treatment approaches

The incidence and mortality rates from endometrial cancer continue to increase worldwide, while rates in most other cancers have either plateaued or declined considerably. Uterine serous carcinoma represents a fraction of all endometrial malignancies each year, yet this histology is responsible for nearly 40% of all endometrial cancer-related deaths. These deaths disproportionately affect black women, who have higher rates of advanced disease at diagnosis. Molecular genetic analyses reveal major alterations including TP53 mutation, PIK3CA mutation/amplification, ERBB2 amplification, CCNE1 amplification, FBXW7 mutation/deletion, PPP2R1A mutation, and somatic mutations involving homologous recombination genes. Clinical risk factors for uterine serous carcinoma include advancing age, a history of breast cancer, tamoxifen usage, and the hereditary breast-ovarian cancer syndrome. Surgery remains the cornerstone of treatment. Recent advances in our understanding of uterine serous carcinoma molecular drivers have led to development of targeted therapeutics that promise improved outcomes for patients. Overexpression or amplification of HER2 in uterine serous carcinoma carries a poor prognosis; yet this actionable target has led to the incorporation of several anti-HER2 therapies, including trastuzumab which, when added to conventional chemotherapy, is associated with improved survival for women with advanced and recurrent HER2-positive disease. The combination of pembrolizumab and lenvatinib is also a promising targeted treatment strategy for women with uterine serous carcinoma, with a recent phase II study suggesting a 50% response rate in women with recurrent disease. Several trials examining additional targeted agents are ongoing. Despite years of stalled progress, meaningful, tailored treatment options are emerging for patients with this uncommon and biologically aggressive endometrial cancer subtype.

Molecular subtypes of clear cell carcinoma of the endometrium: Opportunities for prognostic and predictive stratification

OBJECTIVE

Our aim was to characterize the pathological, molecular and clinical outcomes of clear cell carcinoma of the endometrium (CCC).

METHODS

CCC underwent ProMisE (Proactive Molecular Risk Classifier for Endometrial Cancer) classification identifying four molecular subtypes: i) 'POLEmut' for ECs with pathogenic POLE mutations, ii) 'MMRd', if there is loss of mismatch repair proteins by immunohistochemistry (IHC), iii) 'p53wt' or iv) 'p53abn' based on p53 IHC staining. Clinicopathologic parameters, immune markers (CD3, CD8, CD79a, CD138, PD-1), ER, L1CAM, and outcomes were assessed.

RESULTS

52 CCCs were classified, including 1 (2%) POLEmut, 5 (10%) MMRd, 28 (54%) p53wt and 18 (35%) p53abn. Women with p53abn and p53wt CCCs were older than women with MMRd and POLEmut subtypes. p53wt CCC were distinct from typical p53wt endometrioid carcinomas; more likely to arise in older, thinner women, with advanced stage disease, LVSI and lymph node involvement, and a higher proportion ER negative, L1CAM overexpressing tumors with markedly worse outcomes. High levels of immune infiltrates (TIL^high) were observed in 75% of the CCC cohort. L1CAM overexpression was highest within p53abn and p53wt subtypes of CCC.

CONCLUSION

CCC is a heterogeneous disease encompassing all four molecular subtypes and a wide range of clinical outcomes. Outcomes of patients with POLEmut, MMRd and p53abn CCC are not distinguishable from those of other patients with these respective subtypes of EC; p53wt CCC, however, differ from endometrioid p53wt EC in clinical, pathological, molecular features and outcomes. Thus, p53wt CCC of endometrium appear to be a distinct clinicopathological entity within the larger group of p53wt ECs.

Mucinous endometrial cancer: Clinical study of the eleven cases

OBJECTIVE:

In this study, we analyzed surgico-pathologic factors of mucinous type endometrial carcinoma and examined its frequency of recurrence.

METHODS:

In this study, eleven cases, definitely diagnosed as pure mucinous type endometrium carcinoma between January 1993 and May 2013, were reviewed.

RESULTS:

Of 1640 women with endometrium carcinoma, 11 (0.67%) of them had a mucinous cell type. Mean age of the study group was 55 years. According to the FIGO 2009, 10 (90.9%) cases were evaluated as stage I and 1 (9.1%) as stage IIIC1. The presence of lymph node metastasis was noticed in only one (12.5%) of eight patients who underwent lymphadenectomy. In this case, metastasis was detected in the pelvic lymph node. Four patients underwent adjuvant therapy as pelvic radiotherapy. Median follow-up time was 50 months (range, 5–84). Recurrence was observed in one (9.1%) patient with stage IIIC1 endometrial cancer in 30 months after primary surgery. The site of recurrence was only in the upper abdominal region.

CONCLUSION:

Based on our study, mucinous endometrial carcinoma has good prognostic factors, and long term survival can be achieved surgically alone in patients with stage I.

High-resolution copy number analysis of clear cell endometrial carcinoma

Uterine cancer is the 6th leading cause of cancer death amongst American women. Most uterine cancers are endometrial carcinomas (ECs), which are classified into histological subtypes including endometrioid, serous, and clear cell ECs. Somatic copy number alterations (SCNAs) are frequent in serous EC, infrequent in endometrioid ECs, and poorly defined in clear cell ECs. The purpose of this study was to evaluate the occurrence of SCNAs in clinically diagnosed clear cell ECs. Paired tumor-normal DNAs for 51 ECs were hybridized to Illumina Infinium HumanHap650Y or Human660W-Quad Beadchips. Copy number calls were made using the Hidden Markov Model based SNP-FASST2 segmentation algorithm within Nexus Copy Number software (v.6.1). High-level SCNAs were defined as gain of ≥5 copies or homozygous deletion, both <10Mb. GISTIC 1.0, in Nexus, was used to identify statistically significant SCNAs, corrected for multiple testing. One or more high-level SCNAs were detected in 50% of 6 clear cell ECs, 78.6% of 28 serous ECs, and 17.6% of 17 endometrioid ECs. A positive association was found between high-level SCNAs and TP53 mutation across ECs (two-tailed p value<0.0001). Classifying tumors according to POLE, MSI, and TP53 status yielded four molecular subgroups; copy number altered tumors were more frequent in the TP53-mutated subgroup (95.8%) than in the unspecified subgroup (22.2%), and absent from the POLE and MSI subgroups. In conclusion, our study provides evidence of inter-tumor heterogeneity in the extent to which SCNAs occur in clinically diagnosed clear cell EC, and across molecular subgroups of EC. The co-occurrence of high-level SCNAs and TP53 mutations in some clear cell ECs is consistent with the view that a subset of clinically diagnosed clear cell ECs have molecular similarities to serous ECs.

Contemporary management of uterine clear cell carcinoma: A Society of Gynecologic Oncology (SGO) review and recommendation

Uterine clear cell cancer (UCCC) is a rare but aggressive disease. Due to its rarity, large, prospective studies focused on UCCC are exceedingly difficult therefore available data are generally from small, retrospective studies. There is also pertinent information from subsection analysis of larger studies that include UCCC and other histotypes. In 2009, the clinical practice committee of the Society of Gynecologic Oncology (SGO) published a review on UCCC aimed at guiding management. Since that publication, there have been developments which are relevant to UCCC, these include availability of data from landmark trials regarding adjuvant therapy, increasing utilization of sentinel lymph node approach and availability of immunotherapy as a treatment option. This SGO review is updated with all relevant, published information since 2009 considered clinically important for management of UCCC. In addition, it follows the new SGO's style for this type of publication which includes utilization of the question and answer format.

High-grade Endometrial Carcinomas: Morphologic and Immunohistochemical Features, Diagnostic Challenges and Recommendations

This review of challenging diagnostic issues concerning high-grade endometrial carcinomas is derived from the authors' review of the literature followed by discussions at the Endometrial Cancer Workshop sponsored by the International Society of Gynecological Pathologists in 2016. Recommendations presented are evidence-based, insofar as this is possible, given that the levels of evidence are weak or moderate due to small sample sizes and nonuniform diagnostic criteria used in many studies. High-grade endometrioid carcinomas include FIGO grade 3 endometrioid carcinomas, serous carcinomas, clear cell carcinomas, undifferentiated carcinomas, and carcinosarcomas. FIGO grade 3 endometrioid carcinoma is diagnosed when an endometrioid carcinoma exhibits >50% solid architecture (excluding squamous areas), or when an architecturally FIGO grade 2 endometrioid carcinoma exhibits marked cytologic atypia, provided that a glandular variant of serous carcinoma has been excluded. The most useful immunohistochemical studies to make the distinction between these 2 histotypes are p53, p16, DNA mismatch repair proteins, PTEN, and ARID1A. Endometrial clear cell carcinomas must display prototypical architectural and cytologic features for diagnosis. Immunohistochemical stains, including, Napsin A and p504s can be used as ancillary diagnostic tools; p53 expression is aberrant in a minority of clear cell carcinomas. Of note, clear cells are found in all types of high-grade endometrial carcinomas, leading to a tendency to overdiagnose clear cell carcinoma. Undifferentiated carcinoma (which when associated with a component of low-grade endometrioid carcinoma is termed "dedifferentiated carcinoma") is composed of sheets of monotonous, typically dyscohesive cells, which can have a rhabdoid appearance; they often exhibit limited expression of cytokeratins and epithelial membrane antigen, are usually negative for PAX8 and hormone receptors, lack membranous e-cadherin and commonly demonstrate loss of expression of DNA mismatch repair proteins and SWI-SNF chromatin remodeling proteins. Carcinosarcomas must show unequivocal morphologic evidence of malignant epithelial and mesenchymal differentiation.

Issues in the Differential Diagnosis of Uterine Low-grade Endometrioid Carcinoma, Including Mixed Endometrial Carcinomas: Recommendations from the International Society of Gynecological Pathologists

This article provides practical recommendations developed from the International Society of Gynecological Pathologists Endometrial Carcinoma Project to address 4 issues that may arise in the diagnosis of uterine corpus low-grade endometrioid carcinoma: (1) The distinction between atypical hyperplasia and low-grade endometrioid carcinoma. (2) The distinction between low-grade endometrioid carcinoma and serous carcinoma. (3) The distinction between corded and hyalinized or spindle cell variants of low-grade endometrioid carcinoma and carcinosarcoma. (4) The diagnostic criteria for mixed endometrial carcinomas, a rare entity that should be diagnosed only after exclusion of a spectrum of tumors including morphologic variants of endometrioid carcinoma, dedifferentiated endometrial carcinoma, carcinosarcoma, and endometrial carcinomas with ambiguous morphology.

Verteporfin exhibits YAP-independent anti-proliferative and cytotoxic effects in endometrial cancer cells

Endometrial Carcinoma (EMCA) is the most common gynecologic malignancy and the fourth most common malignancy in women in the United States. Yes-associated protein (YAP) is a potent transcription coactivator acting via binding to the TEAD transcription factor, and plays a critical role in organ size regulation. Verteporfin (VP), a benzoporphyrin derivative, was identified as an inhibitor of YAP-TEAD interaction. We investigated the therapeutic efficacy and mechanism of VP in EMCA. The efficacy of VP on cell viability, cytotoxicity and invasion was assayed in EMCA cell lines. An organoid model system was also developed to test the effect of VP on apoptotic markers in an in vitro model system. Treatment with VP resulted in a decrease in cell viability, invasion and an increase in cytotoxicity of EMCA cells. These effects occurred as early as 15 minutes following treatment. Similarly, VP treatment versus vehicle control increased apoptosis in human organoid model systems. Quantitative RT-PCR, cDNA based RTPCR array analysis and western blotting were performed to investigate the mechanism of VP action. The cytotoxic and anti-proliferative effects appeared to be independent of its effect on YAP. Our results suggest that VP is a promising chemotherapeutic agent for the treatment of endometrial cancer.

In Vitro and In Vivo Activity of IMGN853, an Antibody-Drug Conjugate Targeting Folate Receptor Alpha Linked to DM4, in Biologically Aggressive Endometrial Cancers

Grade 3 endometrioid and uterine serous carcinomas (USC) account for the vast majority of endometrial cancer deaths. The purpose of this study was to determine folic acid receptor alpha (FRα) expression in these biologically aggressive (type II) endometrial cancers and evaluate FRα as a targetable receptor for IMGN853 (mirvetuximab soravtansine). The expression of FRα was evaluated by immunohistochemistry (IHC) and flow cytometry in 90 endometrioid and USC samples. The in vitro cytotoxic activity and bystander effect were studied in primary uterine cancer cell lines expressing differential levels of FRα. In vivo antitumor efficacy of IMGN853 was evaluated in xenograft/patient-derived xenograft (PDX) models. Semiquantitative IHC analysis indicated that 41% of the USC patients overexpress FRα. Further, overexpression of FRα (i.e., 2+) was detected via flow cytometry in 22% (2/9) of primary endometrioid and in 27% (3/11) of primary USC cell lines. Increased cytotoxicity was seen with IMGN853 treatment compared with control in 2+ expressing uterine tumor cell lines. In contrast, tumor cell lines with low FRα showed no difference when exposed to IMGN853 versus control. IMGN853 induced bystander killing of FRα = 0 tumor cells. In an endometrioid xenograft model (END(K)265), harboring 2+ FRα, IMGN853 treatment showed complete resolution of tumors (P < 0.001). Treatment with IMGN853 in the USC PDX model (BIO(K)1), expressing 2+ FRα, induced twofold increase in median survival (P < 0.001). IMGN853 shows impressive antitumor activity in biologically aggressive FRα 2+ uterine cancers. These preclinical data suggest that patients with chemotherapy resistant/recurrent endometrial cancer overexpressing FRα may benefit from this treatment. Mol Cancer Ther; 17(5); 1003-11. ©2018 AACR.

Does a p53 "Wild-type" Immunophenotype Exclude a Diagnosis of Endometrial Serous Carcinoma?

An aberrant p53 immunophenotype may be identified in several histotypes of endometrial carcinoma, and is accordingly recognized to lack diagnostic specificity in and of itself. However, based on the high frequency with which p53 aberrations have historically been identified in endometrial serous carcinoma, a mutation-type immunophenotype is considered to be highly sensitive for the histotype. Using an illustrative case study and a review of the literature, we explore a relatively routine diagnostic question: whether the negative predictive value of a wild-type p53 immunophenotype for serous carcinoma is absolute, that is, whether a p53-wild type immunophenotype is absolutely incompatible with a diagnosis of serous carcinoma. The case is an advanced stage endometrial carcinoma that was reproducibly classified by pathologists from 3 institutions as serous carcinoma based on its morphologic features. By immunohistochemistry, the tumor was p53-wild type (DO-7 clone), diffusely positive for p16 (block positivity), and showed retained expression of PTEN, MSH2, MSH6, MLH1, and PMS2. Next generation sequencing showed that there indeed was an underlying mutation in TP53 (D393fs*78, R213*). The tumor was microsatellite stable, had a low mutational burden (4 mutations per MB), and displayed no mutations in the exonuclease domain of DNA polymerase epsilon (POLE) gene. Other genomic alterations included RB1 mutation (R46fs*19), amplifications in MYST3 and CRKL, and ARID1A deletion (splice site 5125-94_5138del108). A review of the recent literature identified 5 studies in which a total of 259 cases of serous carcinoma were whole-exome sequenced. The average TP53 mutational rate in endometrial serous carcinoma was only 75% (range, 60 to 88). A total of 12 (33%) of 36 immunohistochemical studies reported a p53-aberrant rate of <80% in endometrial serous carcinoma. We discuss in detail several potential explanations that may underlie the scenario of serous carcinoma-like morphology combined with p53-wild-type immunophenotype, including analytic limitations, a nonserous histotype displaying morphologic mimicry of serous carcinoma, and true biological phenomena (including the possibility of a TP53-independent pathway of endometrial serous carcinogenesis). Ultimately, our central thematic question is provisionally answered in the negative. At present, the available data would not support a categorical conclusion that a p53 alteration is a necessary and obligate component in the genesis and/or diagnosis of endometrial serous carcinoma. On the basis of their collective experience, the authors proffer some recommendations on the use of p53 immunohistochemistry in the histotyping of endometrial carcinomas.

Surgical-pathological findings in type 1 and 2 endometrial cancer: An NRG Oncology/Gynecologic Oncology Group study on GOG-210 protocol

OBJECTIVE

To report clinical and pathologic relationships with disease spread in endometrial cancer patients.

METHODS

Surgical candidates with uterine cancer (adenocarcinoma or carcinosarcoma) who were eligible to participate in a surgical pathological study to create a clinically annotated tissue biorepository to support translational and clinical research studies. All patients were to undergo a hysterectomy, bilateral salpingo-oophorectomy, and bilateral pelvic and para-aortic lymphadenectomy. From 2003-2007, open eligibility enrollment was conducted, and from 2007-2011, eligibility was restricted to enrich underrepresented patients or those at high risk.

RESULTS

This report details clinical pathological relationships associated with extra uterine disease spread of 5866 evaluable patients including those with endometrioid histology as well as papillary serous, clear cell and carcinosarcoma histologies. Review of unrestricted enrollment was constructed in an effort to capture a cross-section population representative of endometrial cancers seen by the GOG participating members. Evaluation of this group of patients suggested the more natural incidence of different surgical pathological findings as well as demographic information. The addition of 2151 patients enrolled during the restricted time interval allowed a total of 1630 poor histotype patients available for further analysis. As expected, endometrioid (E) cancers represented the largest enrollment and particularly E grade 1 and 2 (G1 and 2) were more frequently confined to the uterus. Grade 3 (G3) endometrioid cancers as well as the poor histotype (papillary serous, clear cell and carcinosarcoma) had a much greater propensity for extant disease.

CONCLUSIONS

This study confirms the previously reported surgical pathological findings for endometrioid cancers but in addition, using a large database of papillary serous, clear cell and carcinosarcoma, surgical pathological findings substantiate the categorization of poor histotypes for these cancers.

Endometrial Carcinomas With Clear Cells: A Study of a Heterogeneous Group of Tumors Including Interobserver Variability, Mutation Analysis, and Immunohistochemistry With HNF-1β

Endometrial clear cell carcinoma (CC) is an uncommon tumor and often carries a poor prognosis. It has histologic features that overlap with other endometrial carcinomas and is frequently misclassified. Accurate classification is crucial, however, to improve treatment options. The objectives of this study were (1) to assess diagnostic interobserver variability among 5 gynecologic pathologists for tumors originally diagnosed as CC or with a component of CC (n=44); (2) to determine the utility of immunohistochemical markers estrogen receptor and HNF-1β; and (3) to detect mutations in select genes. Clinical data and morphologic features were also recorded. Agreement among reviewers was only moderate: only 46% of the original CC remained classified as such. After reclassification, estrogen receptor was positive in 8% of CC, 67% of endometrioid carcinomas (EC), and 47% of serous carcinomas (SC). Sensitivities of HNF-1β in CC, SC, and EC were 62%, 27%, and 17%, respectively, whereas specificity for CC versus EC or SC was 78%. Mutations in PIK3CA, PIK3R1, PTEN, KRAS, and NRAS were detected in 41% of 37 cases that had adequate material for study. At least 1 mutation was identified in 33% of CC, 67% of EC, and 33% of SC. This group of patients had poor outcomes: 72% of the patients with follow-up information had died of disease. In summary, this study suggests that the current pool of CC is a heterogeneous group of tumors from the morphologic, immunophenotypic, and molecular point of views and that only a percentage of them represent true CC.

Impact of histology and surgical approach on survival among women with early-stage, high-grade uterine cancer: An NRG Oncology/Gynecologic Oncology Group ancillary analysis

OBJECTIVES

We sought to analyze the clinicopathologic features, recurrence patterns and survival outcomes of women with high-grade uterine cancer (UC) enrolled on The Gynecologic Oncology Group (GOG) LAP2 trial.

METHODS

This is a post-hoc analysis of LAP-2 patients with grade 3 endometrioid adenocarcinoma (ENDO), uterine serous (USC), clear cell (CC) and carcinosarcoma (CS). Demographics, clinicopathologic features, and recurrence patterns, were compared by histology and surgical approach. Progression-free survival (PFS) and overall survival (OS) were estimated using the Kaplan-Meier method.

RESULTS

Of the 2600 patients enrolled in LAP-2, 753 patients had high-grade UC: 350 had ENDO, 289 had USC, 42 had CC and 72 had CS. Compared with the ENDO cohort, those with other high-grade subtypes were older (p<0.001) and were more likely to have positive peritoneal cytology (p<0.001), positive lymph nodes (p=0.05) and higher disease stage on final pathology (p<0.001). With a median follow-up time of 60months, compared to patients with ENDO, those with USC, CCC and CS subtypes had higher recurrence rates (p<0.001), extra-pelvic recurrences (p<0.001) and poorer PFS (p<0.001) and OS (p<0.001). Those diagnosed with USC and CS experienced the worst survival outcomes (p=0.003). Patterns of recurrence and survival were not different in those staged with LSC vs LAP. On multivariable analysis, age, stage, pelvic washings and Type II histology were independently and adversely associated with survival.

CONCLUSIONS

Women with apparent early-stage, USC and CS histologies have poorer outcomes than women with grade 3 endometrioid adenocarcinoma. Patterns of recurrence and survival were not impacted by surgical approach.

Serous carcinoma of endometrium in combination with neuroendocrine small-cell: A case report and literature review

Endometrial serous carcinomas are very clinically aggressive, which constitutes 40% of all deaths and recurrences associated with endometrial cancer. Small-cell carcinoma of the endometrium is relatively rare but aggressive, and often presents a component of endometrioid carcinoma, and is not generally associated with serous carcinoma. Herein, we report a case of 74-year-old African-American female, who presented with intermittent post-menopausal bleeding for > 1-month. She underwent robotic-assisted laparoscopic hysterectomy, bilateral salpingo-oophorectomy, sentinel lymph node mapping, and pelvic-and-aortic lymphadenectomy. Final pathology was consistent with serous carcinoma of the endometrium in combination with neuroendocrine small-cell carcinoma. This extremely rare combination of tumors presents a challenge for treatment. The mainstay of treatment seems to be surgery followed by chemotherapy ± radiation therapy. To our knowledge, it represents an under-reported area of gynecological medicine.

•

Small-cell carcinoma of endometrium is rare but aggressive and challenging to care.

•

We report a case presenting with intermittent post-menopausal bleeding for > 1-month.

•

She underwent robotic hysterectomy, BSO, SLN mapping, and complete lymphadenectomy.

•

Pathology revealed serous carcinoma of endometrium combined with neuroendocrine SCC.

•

To our knowledge, it represents an under-reported area of gynecological medicine.

Molecular Analysis of Mixed Endometrial Carcinomas Shows Clonality in Most Cases

Mixed endometrial carcinoma refers to a tumor that comprises 2 or more distinct histotypes. We studied 18 mixed-type endometrial carcinomas-11 mixed serous and low-grade endometrioid carcinomas (SC/EC), 5 mixed clear cell and low-grade ECs (CCC/EC), and 2 mixed CCC and SCs (CCC/SC), using targeted next-generation sequencing and immunohistochemistry to compare the molecular profiles of the different histotypes present in each case. In 16 of 18 cases there was molecular evidence that both components shared a clonal origin. Eight cases (6 EC/SC, 1 EC/CCC, and 1 SC/CCC) showed an SC molecular profile that was the same in both components. Five cases (3 CCC/EC and 2 SC/EC) showed a shared endometrioid molecular profile and identical mismatch-repair protein deficiency in both components. A single SC/EC case harbored the same POLE exonuclease domain mutation in both components. One SC/CCC and 1 EC/CCC case showed both shared and unique molecular features in the 2 histotype components, suggesting early molecular divergence from a common clonal origin. In 2 cases, there were no shared molecular features, and these appear to be biologically unrelated synchronous tumors. Overall, these results show that the different histologic components in mixed endometrial carcinomas typically share the same molecular aberrations. Mixed endometrial carcinomas most commonly occur through morphologic mimicry, whereby tumors with serous-type molecular profile show morphologic features of EC or CCC, or through underlying deficiency in DNA nucleotide repair, with resulting rapid accrual of mutations and intratumoral phenotypic heterogeneity. Less commonly, mixed endometrial carcinomas are the result of early molecular divergence from a common progenitor clone or are synchronous biologically unrelated tumors (collision tumors).

Practical issues in the diagnosis of serous carcinoma of the endometrium

Serous carcinoma (SC) represents ~10% of endometrial carcinomas, but is responsible for almost 40% of cancer deaths. This article reviews the main pathological features, differential diagnosis, and the usefulness of molecular pathology and immunohistochemistry in its diagnosis. Most helpful features for the diagnosis include: irregularly shaped and sized papillae, slit-like spaces, cell stratification and budding, highly atypical cells, architectural and cytological discordance in pseudoglandular tumors, as well as lack of endometrioid features. SC shows typically a predominant papillary growth, which is also found in some subtypes of endometrioid carcinoma of the endometrium (EEC). Distinction is easy when attention is paid to the presence of diffuse marked nuclear pleomorphism, but also to the complex papillary architecture. SC may also show a solid or pseudoglandular patterns, and in these cases differential diagnosis may be difficult with EEC grade 3. Moreover, a high proportion of SC may exhibit clear cells, and, thus, may be confused with clear cell carcinoma. Finally, it is sometimes difficult to distinguish mixed SC-EEC, from SC that combines papillary and pseudoglandular growths. Although there is not a single immunohistochemical marker for distinguishing SC from its mimickers, some antibodies are useful (p53, p16, IMP2, and IMP3), particularly when used in combination. Diagnosis of SC may be even more problematic in small biopsies; a diagnosis of high-grade endometrial carcinoma, SC component can not be excluded, is acceptable as a managerial approach, so it could be taken into account at the time of final surgery.

The impact of combined radiation and chemotherapy on outcome in uterine papillary serous carcinoma compared to chemotherapy alone

OBJECTIVE

To investigate the impact of pelvic radiation on survival in patients with uterine serous carcinoma (USC) who received adjuvant chemotherapy.

METHODS

Patients with stage I-IV USC were identified from the Surveillance, Epidemiology, and End Results program 2000 to 2009. Patients were included if treated with surgery and chemotherapy. Patients were divided into two groups: those who received chemotherapy and pelvic radiation therapy (CT_RT) and those who received chemotherapy only (CT). Kaplan-Meier curves and Cox regression proportional hazard models were used.

RESULTS

Of the 1,838 included patients, 1,272 (69%) were CT and 566 (31%) were CT_RT. Adjuvant radiation was associated with significant improvement in overall survival (OS; p<0.001) and disease-specific survival (DSS; p<0.001) for entire cohort. These findings were consistent for the impact of radiation on OS (p<0.001) and DSS (p<0.001) in advanced stage (III-IV) disease but not for early stage (I?II) disease (p=0.21 for OS and p=0.82 for DSS). In multivariable analysis adjusting for age, stage, race and extent of lymphadenectomy, adjuvant radiation was a significant predictor of OS and DSS for entire cohort (p=0.003 and p=0.05) and in subset of patients with stage III (p=0.02 and p=0.07) but not for patients with stage I (p=0.59 and p=0.49), II (p=0.83 and p=0.82), and IV USC (p=0.50 and p=0.96). Other predictors were stage, positive cytology, African American race and extent of lymphadenectomy.

CONCLUSION

In USC patients who received adjuvant chemotherapy, adjuvant radiation was associated with significantly improved outcome in stage III disease but not for other stages. Positive cytology, extent of lymphadenectomy and African race were significant predictors of outcome.

Alteration in PI3K/mTOR, MAPK pathways and Her2 expression/amplification is more frequent in uterine serous carcinoma than ovarian serous carcinoma

OBJECTIVES

To compare the molecular profile of a large cohort of uterine papillary serous carcinoma (UPSC) and ovarian serous carcinoma (EOC-S).

METHODS

628 UPSC and 5335 EOC-S tumors were evaluated using a commercial multiplatform profiling service (CARIS Life Sciences, Phoenix, AZ). Specific testing performed included a combination of gene sequencing (Sanger, next generation sequencing), protein expression (IHC) and gene amplification (CISH or FISH).

RESULTS

TP53 was the most commonly mutated gene in both UPSC and EOC-S (76% vs. 69%, P = 0.03). UPSC were more likely to have mutation in PIK3CA (29% vs. 2%, P < 0.001), FBXW7 (12% vs. 1%, P < 0.001), KRAS (9% vs. 5%, P < 0.001) PTEN (7% vs. 1%, P < 0.001), and CTNNB1 (2% vs. 0%, P < 0.001) compared to EOC-S. On the other hand, EOC-S were more likely to harbor mutation in BRCA1 (20% vs. 9% P = 0.17) and BRCA2 (18% vs. 6% P = 0.09). HER2 gene amplification (17% vs. 4%, P < 0.001) and Her2/neu expression (10% vs. 2%, P < 0.001) were more frequent in UPSC than EOC-S, respectively.

CONCLUSION

UPSC have a distinct mutation profile indicating higher activity of PI3K/AKT/mTOR, and MAPK pathways and Her2 expression/amplification but a trend toward lower frequency of alteration in homologous recombination pathway compared to EOC-S. Targeted PI3K/AKT/mTOR inhibitors should be evaluated in UPSC.

Endometrial Cancers in Mutation Carriers From Hereditary Breast Ovarian Cancer Syndrome Kindreds: Report From the Creighton University Hereditary Cancer Registry With Review of the Implications

Objective

The aim of this study was to categorize and report endometrial cancers in mutation carriers from hereditary breast ovarian cancer families.

Methods

Our Hereditary Cancer Registry was searched for gynecologic and peritoneal cancers linked to mutations in BRCA1 or BRCA2. Invasive cancers were registered in 101 mutation carriers with complete pathology reports. Efforts were made to secure diagnostic surgical pathology tissues for review. All records and available diagnostic slides were meticulously studied, and primary cancers were classified.

Findings

Eight malignancies were classified as primary endometrial cancers. Five of these were low- or intermediate-grade endometrioid carcinomas, and 3 were pure serous carcinomas or contained serous carcinoma elements mixed with high-grade endometrioid carcinoma. Breast cancers were diagnosed in 5 patients before and in 1 patient after endometrial carcinoma. Three endometrioid carcinomas were preceded by estrogen treatment, 2 for many years and the other for only 2 months, and 2 of the patients with serous carcinoma had been treated with tamoxifen.

Conclusions

The finding that 8 of gynecologic and peritoneal cancers in 101 mutation carriers were endometrial cancers with a smaller proportion of endometrioid carcinomas than reported in general populations is added to the current controversial literature on endometrial cancer, particularly regarding serous carcinomas, in hereditary breast ovarian cancer syndrome. Well-designed prospective programs for standardized surgical and pathologic handling, processing, and reporting are essential for working out the pathogenesis, true risks, and best management of this disease in carriers of deleterious BRCA1 and BRCA2 germline mutations.

Prognostic impact of lymphadenectomy in uterine clear cell carcinoma

Objective

The aim of this study was to estimate the survival impact of lymphadenectomy in patients diagnosed with uterine clear cell cancer (UCCC).

Methods

Patients with a diagnosis of UCCC were identified from Surveillance, Epidemiology, and End Results (SEER) program from 1988 to 2007. Only surgically treated patients were included. Statistical analysis using Student t-test, Kaplan-Meier survival methods, and Cox proportional hazard regression were performed.

Results

One thousand three hundred eighty-five patients met the inclusion criteria; 955 patients (68.9%) underwent lymphadenectomy. Older patients (≥65) were less likely to undergo lymphadenectomy compared with their younger cohorts (64.3% vs. 75.9%, p<0.001). The prevalence of nodal metastasis was 24.8%. Out of 724 women who had disease clinically confined to the uterus and underwent lymphadenectomy, 123 (17%) were found to have nodal metastasis. Lymphadenectomy was associated with improved survival. Patients who underwent lymphadenectomy were 39% (hazard ratio [HR], 0.61; 95% confidence interval [CI], 0.52 to 0.72; p<0.001) less likely to die than patient who did not have the procedure. Moreover, more extensive lymphadenectomy correlated positively with survival. Compared to patients with 0 nodes removed, patients with more extensive lymphadenectomy (1 to 10 and >10 nodes removed) were 32% (HR, 0.68; 95% CI, 0.56 to 0.83; p<0.001) and 47% (HR, 0.53; 95% CI, 0.43 to 0.65; p<0.001) less likely to die, respectively.

Conclusion

The extent of lymphadenectomy is associated with an improved survival of patients diagnosed with UCCC.

Impact of adjuvant chemotherapy and pelvic radiation on pattern of recurrence and outcome in stage I non-invasive uterine papillary serous carcinoma. A multi-institution study

OBJECTIVES

To determine the impact of adjuvant chemotherapy or pelvic radiation on risk of recurrence and outcome in stage IA non-invasive uterine papillary serous carcinoma (UPSC).

METHODS

This is a multi-institutional retrospective study for 115 patients with stage IA non-invasive UPSC (confined to endometrium) treated between 2000 and 2012. Kaplan-Meier and multivariable Cox proportional hazards regression modeling were used.

RESULTS

Staging lymphadenectomy and omentectomy were performed in 84% and 57% respectively. Recurrence was seen in 26% (30/115). Sites of recurrences were vaginal in 7.8% (9/115), pelvic in 3.5% (4/115) and extra-pelvic in 14.7% (17/115). Adjuvant chemotherapy did not impact risk of recurrence (25.5% vs. 26.9%, p=0.85) even in subset of patients who underwent lymphadenectomy (20% vs. 23.5%, p=0.80). These findings were consistent for pattern of recurrence. Among those who underwent lymphadenectomy, adjuvant chemotherapy did not impact progression-free survival (p=0.34) and overall survival (p=0.12). However among patients who did not have lymphadenectomy, adjuvant chemotherapy or pelvic radiation was associated with longer progression-free survival (p=0.04) and overall survival (p=0.025). In multivariable analysis, only staging lymphadenectomy was associated with improved progression-free survival (HR 0.34, 95% CI 0.12-0.95, p=0.04) and overall survival (HR 0.35, 95% CI 0.12-1.0, p=0.05). Neither adjuvant chemotherapy nor pelvic radiation were predictors of progression-free or overall survivals.

CONCLUSION

In stage IA non-invasive UPSC, staging lymphadenectomy was significantly associated with recurrence and outcome and therefore, should be performed in all patients. Adjuvant chemotherapy or pelvic radiation had no impact on outcome in surgically staged patients but was associated with improved outcome in unstaged patients.

Yes-associated protein (YAP) modulates oncogenic features and radiation sensitivity in endometrial cancer

BACKGROUND

Yes-associated protein (YAP) is a transcriptional co-activator and regulates cell proliferation and apoptosis. We investigated the clinical and biological significance of YAP in endometrial cancer (EMCA).

METHODS

YAP expression in 150 primary tumor tissues from patients with EMCA was evaluated by immunohistochemistry and its association with clinicopathological data was assessed. The biological functions of YAP were determined in EMCA cell lines through knockdown/overexpression of YAP. The role of YAP in modulating radiation sensitivity was also investigated in EMCA cells.

RESULTS

Increased nuclear YAP expression was significantly associated with higher grade, stage, lympho-vascular space invasion, postoperative recurrence/metastasis and overall survival in estrogen mediated EMCA, called type 1 cancer (p = 0.019,  = 0.028,  = 0.0008,  = 0.046 and  = 0.015, respectively). In multivariate analysis, nuclear YAP expression was confirmed as an independent prognostic factor for overall survival in type 1 EMCA. YAP knockdown by siRNA resulted in a significant decrease in cell proliferation (p<0.05), anchorage-dependent growth (p = 0.015) and migration/invasion (p<0.05), and a significant increase in the number of cells in G0/G1 phase (p = 0.002). Conversely, YAP overexpression promoted cell proliferation. Clonogenic assay demonstrated enhanced radiosensitivity by approximately 36% in YAP inhibited cells.

CONCLUSIONS

Since YAP functions as a transcriptional co-activator, its differential localization in the nucleus of cancer cells and subsequent impact on cell proliferation could have important consequences with respect to its role as an oncogene in EMCA. Nuclear YAP expression could be useful as a prognostic indicator or therapeutic target and predict radiation sensitivity in patients with EMCA.

Reproducibility of histological cell type in high-grade endometrial carcinoma

Subclassification of endometrial carcinoma according to histological type shows variable interobserver agreement. The aim of this study was to assess specifically the interobserver agreement of histological type in high-grade endometrial carcinomas, recorded by gynecological pathologists from five academic centers across Canada. In a secondary aim, the agreement of consensus diagnosis with immunohistochemical marker combinations was assessed including six routine (TP53, CDKN2A (p16), ER, PGR, Ki67, and VIM) and six experimental immunohistochemical markers (PTEN, ARID1A, CTNNB1, IGF2BP3, HNF1B, and TFF3). The paired interobserver agreement ranged from κ 0.50 to 0.63 (median 0.58) and the intraobserver agreement from κ 0.49 to 0.67 (median 0.61). Consensus about histological type based on morphological assessment was reached in 72% of high-grade endometrial carcinomas. A seven-marker immunohistochemical panel differentiated FIGO grade 3 endometrioid from serous carcinoma with a 100% concordance rate compared with the consensus diagnosis. More practically, a three-marker panel including TP53, ER, and CDKN2A (p16) can aid in the differential diagnosis of FIGO grade 3 endometrioid from endometrial serous carcinoma. Our study demonstrates that the inter- and intraobserver reproducibility of histological type based on morphology alone are mostly moderate. Ancillary techniques such as immunohistochemical marker panels are likely needed to improve diagnostic reproducibility of histological types within high-grade endometrial carcinomas.

Coordinate patterns of estrogen receptor, progesterone receptor, and Wilms tumor 1 expression in the histopathologic distinction of ovarian from endometrial serous adenocarcinomas

The purpose of this study is to assess whether composite or coordinate immunoexpression patterns of estrogen receptor (ER), progesterone receptor (PR), and Wilms tumor 1 (WT1) gene can significantly distinguish between endometrial serous carcinoma (ESC) and ovarian serous carcinoma (OSC). Immunohistochemical analyses were performed on whole tissue sections from 22 uterus-confined ESCs and on a tissue microarray of 140 high-grade, pan-stage OSCs, using antibodies to ER, PR, and WT-1. Estrogen receptor, PR, and WT1 expressions were present in 37%, 49%, and 81% of OSC, respectively, but these markers were also present in 18%, 27%, and 36% of ESC. The ER+/PR+/WT1+ coordinate profile was identified in 33.6% of OSC but in none of ESC (P = .0006), resulting in a calculated sensitivity and specificity of this profile for OSC of 33.6% and 100%, respectively. By contrast, the ER-/PR-/WT1- coordinate profile was identified in 41% of ESC but in only 6.4% of OSC (P = .0001), resulting in a calculated sensitivity and specificity of this profile for ESC of 50% and 94%. In summary, in the differential diagnosis between OSC and ESC, positivity for all 3 markers favors an extrauterine origin, whereas negativity for all 3 markers is supportive of an endometrial origin. The use of single markers for this purpose is not recommended, as each lacks optimal discriminatory power. Coordinate profiles, in general, have a high specificity but low sensitivity in this differential diagnosis.

Gemcitabine for advanced endometrial cancer: a retrospective study of the Memorial sloan-Kettering Cancer Center experience

BACKGROUND

Gemcitabine is active in several gynecologic malignancies including ovarian cancer, cervical cancer, and uterine leiomyosarcoma. It has been used in an off-label setting for the treatment of advanced endometrial cancer, despite lack of published data showing efficacy. We performed a retrospective study to determine the progression-free survival and response rate of endometrial cancer patients treated with gemcitabine at Memorial Sloan-Kettering Cancer Center.

METHODS

Eligible patients had histologically confirmed advanced (stage IV or recurrent) endometrial cancer that was treated with single-agent gemcitabine at Memorial Sloan-Kettering Cancer Center between 1999 and 2009. Response to therapy was determined by review of computed tomography imaging by Response Evaluation Criteria in Solid Tumors 1.1 criteria.

RESULTS

Forty-six patients were included in the analysis. Median age was 66 years (range, 52-87 years). All patients were previously treated with chemotherapy. The median number of prior lines of chemotherapy was 2 (range, 1-8). Median dose of gemcitabine administered was 800 mg/m infused on days 1 and 8 of a 21-day cycle. Predominant histology was endometrioid (48%, n = 22) followed by serous (35%, n = 16), clear cell (15%, n = 7), and undifferentiated (2%, n = 1). Overall response rate was 10.9% (95% confidence interval, 1.9%-19.9%); 5 patients (11%) achieved a partial response. Thirteen patients (28%) displayed stable disease lasting at least 3 months. Of note, 5 (71%) of the 7 patients with clear cell histology displayed stable disease or partial response (n = 5). The median progression-free survival was 3.0 months (95% confidence interval, 2.1-3.3 months). Nonhematologic grades 3 and 4 toxicities were rare. Ten patients (22%) were treated with granulocyte colony-stimulating factor during treatment. Grade 3 thrombocytopenia was seen in 4 patients (9%). There were no cases of grade 4 thrombocytopenia.

CONCLUSIONS

In a mixed population of patients with previously treated advanced endometrial cancer, gemcitabine was well tolerated and showed modest activity. Patients with clear cell histology appeared to have greater likelihood of benefit.

Mucinous adenocarcinoma of the endometrium: case series and review of the literature

OBJECTIVE

Mucinous carcinoma of the endometrium (MCE) is a rare histologic type representing less than 5% of all endometrial carcinomas. The aim of the study was to describe our experience with MCE and determine its clinical outcome.

METHODS

After institutional review board approval, we performed a comprehensive retrospective review of medical records of patients with uterine adenocarcinoma who underwent surgical staging for MCE in 2 large academic centers between 1990 and 2009. Patients with 2009 International Federation of Gynecology and Obstetrics stages I to III were included. Patients' demographics and tumor characteristics were obtained and analyzed, including data on follow-up and survival.

RESULTS

Thirty-one patients with MCE were identified for the study. Median age was 62 years (range, 43-91 years). All patients underwent surgical staging with lymph node evaluation. Patients' distribution by stage was as follows: 83.9% (n = 26) stage IA, 6.5% (n = 2) stage IIIA, and 9.7% (n = 3) stage IIIC1. Median follow-up was 62 months (range, 1-189 months). Only 30 patients received adjuvant platinum-based chemotherapy. No patients received adjuvant radiation treatment after hysterectomy. Only 4 patients had tumor recurrences with a median time to recurrence of 13.5 months (range, 8-30 months). Three patients with stage IIIC1 and one patient with stage IIIA had a diagnosis of pelvic recurrences. On univariate analysis, factors associated with recurrence were advanced stage (P ≤ 0.0001), deep myometrial invasion (P = 0.0199), lower uterine segment involvement (P = 0.0038), and grade II disease (P = 0.0013). Five-year relapse-free survival was 86.3%, and 5-year overall survival was 81.2%.

CONCLUSIONS

Based on our study cohort, the outcome of patients with FIGO stage I to stage II MCE is excellent with surgical staging alone. However, patients with advanced stages may potentially benefit from adjuvant therapies. These findings need to be validated with other similar studies.

The diagnosis of endometrial carcinomas with clear cells by gynecologic pathologists: an assessment of interobserver variability and associated morphologic features

The purposes of this study are to assess the level of interobserver variability in the diagnosis of endometrial carcinomas with clear cells by gynecologic pathologists based purely on their morphologic features and to comparatively describe the cases of putative clear cell carcinoma (CCC) with and without significant interobserver variability. A total of 35 endometrial carcinomas (1 slide per case) were reviewed by 11 gynecologic pathologists (median experience: 10 y) from 11 North American institutions. The cases were selected from the files of 3 institutions on the basis of the presence of at least focal clear cells and had previously been classified as a variety of histotypes at these institutions. Diagnoses were rendered in a blinded manner and without predetermined diagnostic criteria or categories. The κ values between any pair of observers ranged from 0.18 to 0.69 (combined 0.46), which was indicative of a "moderate" level of interobserver agreement for the group. Subgroups of "confirmed CCC" [cases diagnosed as such by at least 8 (73%) of the 11 observers, n=14] and "possible CCC" (cases diagnosed as CCC by ≥1 but <8 observers, n=13) were compared with regard to a variety of semiquantified morphologic features. By combining selected morphologic features that displayed statistically significant differences between the 2 groups on univariate analyses, the following approximate morphologic profile emerged for the confirmed CCC group: papillae with hyalinized cores in ≥33% of the lesion, clear cells in ≥33% of the lesion, hyperchromasia in ≥33% of the lesion, the absence of nuclear pseudostratification in >3 cells on the papillae, the absence of nuclear pseudostratification in glands in ≥33% of the lesion, the absence of diffuse grade 3 nuclei, the absence of long and slender papillae in ≥33% of the lesion, and glands and papillae lined by cuboidal to flat, noncolumnar cells. In a backward stepwise logistic regression analysis, features from the profile that predicted the confirmed CCC group included: (1) absence or minimality of diffuse sheets of grade 3 nuclei [P=0.025; 95% confidence interval (CI), 0.0266-0.363]; (2) absence or minimality of nuclear stratification in glands and papillae (P=0.040; 95% CI, -0.228 to -0.0054); and (3) glands and papillae lined by cuboidal to flat, noncolumnar cells (P=0.008; 95% CI, 0.0911-0.566). The 2 groups displayed significant overlap regarding a wide variety of features, and no single case displayed a full complement of potentially diagnostic features. Morphologic patterns associated with cases with very high levels of interobserver variability (defined as cases with ≥4 different diagnoses rendered for them, n=9) included the near-exclusive or exclusively solid pattern of clear cells (3/9) and glandular/papillary proliferations whose only CCC-like feature was the presence of clear cells (2/9). In conclusion, the diagnosis of endometrial carcinomas with clear cells by gynecologic pathologists is associated with a moderate level of interobserver variability. However, there is a morphologic profile that characterizes cases that gynecologic pathologists more uniformly classify as CCC, and the presence of these features is supportive of a CCC diagnosis in an endometrial carcinoma with clear cells. Cases that display broad and significant qualitative deviations from the aforementioned profile should prompt the consideration of a diagnosis other than CCC.

Incidence and survival trends of uncommon corpus uteri malignancies in the Netherlands, 1989-2008

INTRODUCTION

Corpus uteri cancer is the most common malignancy of the female reproductive tract in industrialized countries, and its incidence is increasing. Although most of these tumors are of the common endometrial type, there are also many uncommon tumors of the corpus uteri. We examined the incidence and survival of patients with uncommon epithelial tumors, carcinosarcomas, and sarcomas of the corpus uteri diagnosed since 1989.

METHODS

All common and uncommon malignancies of the corpus uteri registered in the nationwide population-based Netherlands Cancer Registry (NCR) during 1989-2008 were included (n = 30,960). The histological subtypes were described according to the Blaustein classification system. Age-standardized incidence for 1989-2008 was calculated per 1,000,000 person-years (p-y), and relative survival was calculated according to the type of uncommon tumor.

RESULTS

The incidence of corpus uteri malignancies increased from 159 to 177 per 1,000,000 p-y, mainly owing to the rise in endometrioid adenocarcinomas from 106 to 144 per 1,000,000 p-y. In contrast, the incidence of uncommon epithelial endometrial carcinomas (UEECs) decreased from 30 to 13 per 1,000,000 p-y, although carcinosarcomas increased slightly from 5.1 to 6.9 per 1,000,000 p-y. Furthermore, a remarkable shift in incidence of endometrial stromal cell sarcomas (ESS) was observed from high-grade ESSs to low-grade ESSs after 2003. Five-year relative survival for patients with UEEC decreased from 72% to 54% and for patients with serous adenocarcinoma from 73% to 51%. Coinciding with an increase in the incidence of common adenocarcinoma of the corpus uteri, there was a decline in uncommon adenocarcinomas and more or less a stable incidence of sarcomas and carcinosarcomas.

CONCLUSION

The decrease in UEEC tumors consisted largely of fewer serous carcinomas, possibly and likely reflecting a more precise histopathological classification of villoglandular tumors. Unfortunately, relative survival for patients with UEEC, sarcomas, and carcinosarcomas did not improve over the study period, indicating a need for more research on treatment strategies for this group of patients.

Does the FIGO 2009 endometrial cancer staging system more accurately correlate with clinical outcome in different histologies? Revised staging, endometrial cancer, histology

OBJECTIVE

In 2009, the International Federation of Gynecology and Obstetrics (FIGO) staging system was revised for endometrial cancers. Different histologies were examined in a large population database. The FIGO 1988 and 2009 staging systems were compared for stage at presentation, differences in patient populations, and disease-specific survival (DSS).

METHODS/MATERIALS

A total of 10,839 cases from 1998 to 2006 were analyzed from the Surveillance, Epidemiology, and End Results (SEER) Program. Examined histologies included 1377 cases of clear cell carcinoma (CC), 2304 cases of uterine papillary serous carcinoma (PS), 755 cases of carcinosarcoma (CS), and 6403 cases of grade 3 endometrial adenocarcinoma (G3A). The median follow-up was 26 months. For each stage and histology, DSS for patient characteristics was examined.

RESULTS

Of the 10,839 women with CC, PS, CS, and G3A had a median age of 67 years. White, black, and other ethnicities composed 87.5%, 12%, and 7% of this group, respectively.A higher percentage of non-G3A histology (CS, PS, and CC) was found in 58% of black women versus 39% of white women. The best to worst 5-year DSS was G3A (76.2%), CC (68.8%), PS (59%), and CS (53.4%). Patients with FIGO IIIC2 disease had inferior survival outcomes in CC (P = 0.0079) and G3A (P = 0.047) compared with FIGO IIIC1 disease, whereas DSS was not significantly different for CS and PS between stages IIIC1 and IIIC2.

CONCLUSIONS

These findings describe differences in the DSS of various aggressive histologies of EC, with poorer DSS in PS, CC, or CS histologies. Analysis demonstrated the usefulness of the new FIGO staging for DSS prediction between stages IIIC1 and IIIC2 for CC and G3A, and 2 divisions for stage I rather than three.

Clear cell carcinoma of the female genital tract (not everything is as clear as it seems)

Clear cell carcinoma has a storied history in the female genital tract. From the initial designation of ovarian clear cell adenocarcinoma as "mesonephroma" to the linkage between vaginal clear cell carcinoma and diethylstilbestrol exposure in utero, gynecologic tract clear cell tumors have puzzled investigators, posed therapeutic dilemmas for oncologists, and otherwise presented major differential diagnostic challenges for pathologists. One of the most common errors in gynecologic pathology is misdiagnosis of clear cell carcinoma, on both frozen section and permanent section. Given the poor response to platinum-based chemotherapy for advanced-stage disease and increased risk of thromboembolism, accurate diagnosis of clear cell carcinoma is important in the female genital tract. This review (1) presents the clinical and pathologic features of female genital tract clear cell carcinomas; (2) highlights recent molecular developments; (3) identifies areas of potential diagnostic confusion; and (4) presents solutions for these diagnostic problems where they exist.