Dedifferentiated Endometrial Carcinoma Could be A Target for Immune Checkpoint Inhibitors (Anti PD-1/PD-L1 Antibodies)

Dedifferentiated Ovarian Carcinoma with ARID1A and ARID1B Mutations: A Clinicopathological Report and Literature Review

Dedifferentiated carcinoma of the female genital tract is a relatively recently recognized aggressive tumor affecting predominantly perimenopausal and postmenopausal women. In addition to having an undifferentiated component, dedifferentiated carcinoma includes a juxtaposed endometrioid adenocarcinoma, FIGO grade 1 or 2. Molecular characterization of these tumors has been a subject of discussion in multiple recent articles. We present a case of dedifferentiated carcinoma of the ovary in a 70-year-old female demonstrating concurrent inactivation of ARID1A and ARID1B. To the best of our knowledge, this is the second clinical report demonstrating dedifferentiated carcinoma of the ovary with concurrent inactivation of ARID1A and ARID1B. ARID1A and ARID1B inactivation seems to represent an alternate mechanism of switch/sucrose nonfermentable complex inactivation in the development of dedifferentiated carcinoma. Additional studies are warranted to precisely understand the molecular mechanism of cellular dedifferentiation in the dedifferentiated endometrial/ovarian carcinomas, thus guiding the development of targeted therapy.

Dedifferentiated Endometrial Carcinoma: A Rare Aggressive Neoplasm-Clinical, Morphological and Immunohistochemical Features

Dedifferentiated endometrioid adenocarcinoma is characterised by the coexistence of an undifferentiated carcinoma and a low-grade endometrioid adenocarcinoma. The low-grade component in this subtype of endometrial carcinoma is Grade 1 or 2 according to the Federation of Gynaecology and Obstetrics (FIGO) grading system. The coexistence of low-grade endometrial carcinoma and solid undifferentiated carcinoma can cause diagnostic problems on histological examination. In fact, this combination can often be mistaken for a more common Grade 2 or Grade 3 endometrial carcinoma. Therefore, this subtype of uterine carcinoma can often go under-recognised. An accurate diagnosis of dedifferentiated endometrial carcinoma is mandatory because of its poorer prognosis compared to Grade 3 endometrial carcinoma, with a solid undifferentiated component that can amount to as much as 20% of the entire tumour. The aim of this review is to provide clinical, immunohistochemical, and molecular data to aid with making an accurate histological diagnosis and to establish whether there are any findings which could have an impact on the prognosis or therapeutic implications of this rare and aggressive uterine neoplasm.

Promising Therapeutic Impact of Immune Checkpoint Inhibitors in Type II Endometrial Cancer Patients with Deficient Mismatch Repair Status

Type II endometrial cancer (EC) is responsible for most endometrial cancer-related deaths due to its aggressive nature, late-stage detection, and high tolerance to standard therapies. Thus, novel treatment strategies for type II EC are imperative. For patients with mismatch repair-deficient (dMMR) tumors, immunotherapy with immune checkpoint inhibitors represents a promising therapeutic strategy. However, the prevalence of dMMR tumors in type II EC patients remains unclear. In this study, using immunohistochemistry, we evaluated the expression of mismatch repair (MMR) proteins, tumor-infiltrating lymphocytes (CD8+), and immune checkpoint molecules (PD-L1) in 60 patients with type II EC (16, 5, 17, and 22 were endometrioid G3, serous, de-differentiated, and carcinosarcoma cases, respectively) to investigate the therapeutic effect of immune checkpoint inhibitors. Approximately 24 cases (40%) had a loss of MMR protein expression. The positivity rate of CD8+ (p = 0.0072) and PD-L1 (p = 0.0061) expression was significantly associated with the dMMR group. These results suggest immune checkpoint inhibitors (anti-PD-L1/PD-1 antibodies) could effectively treat type II EC with dMMR. The presence of dMMR might be a biomarker for a positive response to PD-1/PD-L1 immunotherapy in type II EC.

The Role of Immunohistochemistry Markers in Endometrial Cancer with Mismatch Repair Deficiency: A Systematic Review

The objective of this systematic review was to summarize our current knowledge of the role of immunohistochemistry (IHC) markers for identifying mismatch repair-deficient (MMRd) tumors in endometrial cancer (EC). Identification of MMRd tumors, which occur in 13% to 30% of all ECs, has become critical for patients with colorectal and endometrial cancer for therapeutic management, clinical decision making, and prognosis. This review was conducted by two authors applying the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines using the following terms: “immunohistochemistry and microsatellite instability endometrial cancer” or “immunohistochemistry and mismatch repair endometrial cancer” or “immunohistochemistry and mismatch repair deficient endometrial cancer”. Among 596 retrieved studies, 161 fulfilled the inclusion criteria. Articles were classified and presented according to their interest for the diagnosis, prognosis, and theragnostics for patients with MMRd EC. We identified 10, 18, and 96 articles using IHC expression of two, three, or four proteins of the MMR system (MLH1, MSH2, MHS6, and PMS2), respectively. MLH1 promoter methylation was analyzed in 57 articles. Thirty-four articles classified MMRd tumors with IHC markers according to their prognosis in terms of recurrence-free survival (RFS), overall survival (OS), stage, grade, and lymph node invasion. Theragnostics were studied in eight articles underlying the important concentration of PD-L1 in MMRd EC. Even though the role of IHC has been challenged, it represents the most common, robust, and cheapest method for diagnosing MMRd tumors in EC and is a valuable tool for exploring novel biotherapies and treatment modalities.

Rare Subtype of Endometrial Cancer: Undifferentiated/Dedifferentiated Endometrial Carcinoma, from Genetic Aspects to Clinical Practice

Endometrial cancer (EC) is one of the most common gynecologic cancers worldwide. There were 417,367 newly diagnosed cases and 97,370 deaths due to this disease worldwide in 2020. The incidence rates have increased over time, especially in countries with rapid socioeconomic transitions, and EC has been the most prevalent gynecologic malignancy in Taiwan since 2012. The new EC molecular classifications of The Cancer Genome Atlas (TCGA) Research Network include clear-cell carcinoma, serous carcinoma, and carcinosarcoma, while undifferentiated/dedifferentiated EC (UDEC) is not mentioned, and most previous clinical trials for EC have not included UDEC. UDEC is rare, has an aggressive growth pattern, tends to be diagnosed at an advanced stage, and is resistant to conventional chemotherapy. In this review, case series or case reports on the clinical features and genomic/epigenetic and expression profiles on UDEC data are summarized in order to identify potential molecular targets for current and future research.

Long-Term Survival and Clinicopathological Implications of DNA Mismatch Repair Status in Endometrioid Endometrial Cancers in Hong Kong Chinese Women

To investigate the role of DNA mismatch repair status (MMR) in survival of endometrioid endometrial cancer in Hong Kong Chinese women and its correlation to clinical prognostic factors, 238 patients with endometrioid endometrial cancer were included. Tumor MMR status was evaluated by immunohistochemistry. Clinical characteristics and survival were determined. Association of MMR with survival and clinicopathological parameters were assessed. MMR deficiency (dMMR) was found in 43 cases (16.5%). dMMR was associated with poor prognostic factors including older age, higher stage, higher grade, larger tumor size and more radiotherapy usage. Long-term survival was worse in dMMR compared to the MMR proficient group. The dMMR group had more deaths, shorter disease-specific survival (DSS), shorter disease-free survival (DFS), less 10-year DSS, less 10-year DFS, and more recurrence. The 5-year DSS and 5-year DFS in the dMMR group only showed a trend of worse survival but did not reach statistical significance. In conclusion, dMMR is present in a significant number of endometrioid endometrial cancers patients and is associated with poorer clinicopathological factors and survival parameters in the long run. dMMR should be considered in the risk stratification of endometrial cancer to guide adjuvant therapy and individualisation for longer follow up plan.

Additional Value of PET/CT-Based Radiomics to Metabolic Parameters in Diagnosing Lynch Syndrome and Predicting PD1 Expression in Endometrial Carcinoma

Purpose

We aim to compare the radiomic features and parameters on 2-deoxy-2-[fluorine-18] fluoro-D-glucose (18F-FDG) positron emission tomography/computed tomography (PET/CT) between patients with endometrial cancer with Lynch syndrome and those with endometrial cancer without Lynch syndrome. We also hope to explore the biologic significance of selected radiomic features.

Materials and Methods

We conducted a retrospective cohort study, first using the 18F-FDG PET/CT images and clinical data from 100 patients with endometrial cancer to construct a training group (70 patients) and a test group (30 patients). The metabolic parameters and radiomic features of each tumor were compared between patients with and without Lynch syndrome. An independent cohort of 23 patients with solid tumors was used to evaluate the value of selected radiomic features in predicting the expression of the programmed cell death 1 (PD1), using 18F-FDG PET/CT images and RNA-seq genomic data.

Results

There was no statistically significant difference in the standardized uptake values on PET between patients with endometrial cancer with Lynch syndrome and those with endometrial cancer without Lynch syndrome. However, there were significant differences between the 2 groups in metabolic tumor volume and total lesion glycolysis (p < 0.005). There was a difference in the radiomic feature of gray level co-occurrence matrix entropy (GLCMEntropy; p < 0.001) between the groups: the area under the curve was 0.94 in the training group (sensitivity, 82.86%; specificity, 97.14%) and 0.893 in the test group (sensitivity, 80%; specificity, 93.33%). In the independent cohort of 23 patients, differences in GLCMEntropy were related to the expression of PD1 (r_s =0.577; p < 0.001).

Conclusions

In patients with endometrial cancer, higher metabolic tumor volumes, total lesion glycolysis values, and GLCMEntropy values on 18F-FDG PET/CT could suggest a higher risk for Lynch syndrome. The radiomic feature of GLCMEntropy for tumors is a potential predictor of PD1 expression.

Practice patterns and results of tumor and germline genetic evaluation of women with endometrial cancer in south Louisiana

The objectives were to describe rates of MMRd or MSI-H EC tumors, the prevalence of LS, the practice patterns of EC genetic evaluation and adherence to NCCN guidelines, and to identify disparities in the genetic evaluation of women with EC. A retrospective cohort study was performed on women with EC from 1/2013 to 12/2019, and information collected included demographics, personal and family history, EC diagnosis and treatment, and details of genetic evaluation. Statistical analysis included a multivariable logistic regression to adjust for all covariate effects simultaneously and Fisher exact tests of independence and Wilcoxon rank-sum tests to compare categorical and continuous covariates, respectively. Of the 286 women with EC, 80 EC tumors were tested, and 27.5% were MMRd or MSI-H. Of the 21 women who had germline testing, no cases of LS were identified. Before the NCCN recommended universal tumor testing, 17.6% of women had tumor testing performed compared to 60.0% after February of 2017 (OR = 2.51, 95% CI 1.89-3.32). Advanced cancer stage was nearly associated with an increased likelihood of tumor testing (OR = 1.40, 95% CI 1.00-1.97). No disparities were identified. We described patterns of genetic evaluation and tumor testing results for women with EC in south Louisiana and found similar rates of MMRd or MSI-H EC tumors as previously reported in other populations. Rates of tumor testing increased after the NCCN recommendation for universal tumor testing, but it is critical to identify weaknesses in this process and develop an algorithm to improve care for women with EC.

Clinico-pathological significance of TCGA classification and SWI/SNF proteins expression in undifferentiated/dedifferentiated endometrial carcinoma: A possible prognostic risk stratification

BACKGROUND

Undifferentiated/dedifferentiated endometrial carcinoma (UEC/DDEC) is a heterogeneous entity, which may show any of the TCGA molecular signatures and loss of the switch/sucrose nonfermentable (SWI/SNF) proteins expression.

AIM

To assess the clinico-pathological significance of the TCGA molecular groups and SWI/SNF proteins expression in UEC/DDEC, through a quantitative systematic review.

METHODS

Electronic databases were searched for all studies assessing the TCGA molecular groups, i.e. POLE-mutant, mismatch repair-deficient (MMRd), p53-abnormal (p53abn) and no specific molecular profile (NSMP), and/or the SWI/SNF proteins (SMARCA4/BRG1, SMARCB1/INI1, ARID1B) expression in UEC/DDEC. Student t-test, Fisher's exact test and Kaplan-Meier survival analysis with long-rank test were used to assess differences among groups; a p-value<0.05 was considered significant.

RESULTS

Eight studies were included in the systematic review. Among the TCGA groups, the mean patient age was significantly higher in the p53abn group than in the NSMP group (p = 0.048). The POLE-mutant group showed advanced FIGO stage (III-IV) significantly less commonly than the NSMP (p = 0.003) and MMRd (p = 0.008) groups, and a significantly better prognosis than the NSMP (p = 0.007), MMRd (p = 0.011) and p53abn (p = 0.045) groups.The SWI/SNF-deficient cases showed a significantly worse prognosis than the SWI/SNF-intact cases (p = 0.010), while no significant differences were found regarding patient age and FIGO stage.

CONCLUSIONS

Among UEC/DDEC, POLE-mutant cases show good prognosis, while SWI/SNF-deficient cases show poor prognosis. The other TCGA molecular subtypes seem to be characterized by an intermediate biological behaviour. On this account, UEC/DDEC patients might be subdivided into three risk groups based on POLE and SWI/SNF status. Further studies are necessary in this field.

Magnetic resonance imaging findings in 11 cases of dedifferentiated endometrial carcinoma of the uterus

Purpose

We evaluated magnetic resonance imaging (MRI) findings of dedifferentiated endometrial carcinoma (DEC), comprising undifferentiated carcinoma and low-grade endometrioid carcinoma.

Materials and methods

We recruited 11 patients with pathologically proven DEC treated at our institute. We evaluated primary lesion size, location and signal intensity on MRI, and prognosis. MRI and pathological findings were compared in eight resected patients.

Results

Primary tumors ranged from 16 to 206 mm in diameter. DEC was located at the endometrium in 9 of the 11 patients; the remaining two patients showed diffuse involvement of the enlarged myometrium. These two patients with diffuse involvement type died within 4 months. Of the eight patients who underwent resection, seven had macroscopic intratumoral hemorrhage and six showed a high signal on T1-weighted images or low signal on T2-weighted images. Of the eight resected patients, four had tumor necrosis > 25% and tumor size > 5 cm. In these patients, necrosis appeared as nonenhanced areas on contrast-enhanced MRI.

Conclusion

MRI findings of DEC showed two patterns: mass-forming type and diffuse myometrial type with poor prognosis. Most patients with DEC had intratumoral hemorrhage, and large tumors (> 5 cm) had gross necrosis, which appeared as nonenhanced areas on contrast-enhanced MRI.

Clinico-pathological features associated with mismatch repair deficiency in endometrial undifferentiated/dedifferentiated carcinoma: A systematic review and meta-analysis

BACKGROUND

Endometrial undifferentiated/dedifferentiated carcinoma (UDC/DDC) is a recently described aggressive variant of endometrial carcinoma, which shows mismatch repair (MMR) deficiency in about half of cases.

AIM

To assess whether MMR-deficient UDC/DDC have distinct clinico-pathological features.

MATERIALS AND METHODS

A systematic review and meta-analysis was performed by searching 4 electronic databases from their inception to October 2020 for all studies reporting clinicopathological characteristics of UDC/DDC series. Student t-test (for continuous variables), Cox regression analysis (for overall survival) and odds ratio (OR, for dichotomous variables) were used with a significant p-value < 0.05; data were pooled by using a random effect model.

RESULTS

Twelve studies were included. MMR-deficiency was significantly associated with older age (p = 0.024), p53-wild-type (p = 0.005), ARID1A loss (p = 0.001) and PD-L1 expression (p = 0.019), but not with overall survival (p = 0.307), extension beyond corpus (p = 0.787) or beyond uterus (p = 0.403), presence of a differentiated component (p = 0.461), loss of expression of cytokeratins (p = 0.698), EMA (p = 0.309), estrogen receptor (p = 0.605), PAX8 (p = 0.959), SMARCA4/BRG1 (p = 0.321), SMARCB1/INI1 (p = 0.225) or claudin-4 (p = 0.094), or POLE exonuclease domain mutation p = (0.773).

CONCLUSIONS

In UDC/DDC, MMR-deficiency appears associated with older age, p53-wild type and ARID1A loss, suggesting the possibility of a distinct pathway underlying dedifferentiation; the association with PD-L1 expression is attributable to the high mutational load and may have therapeutic implications. On the other hand, MMR-deficiency appears not to be associated with prognosis, stage, loss of differentiation markers or POLE mutation.

SWI/SNF-deficiency defines highly aggressive undifferentiated endometrial carcinoma

Dedifferentiated/undifferentiated endometrial carcinoma (DDEC/UEC) is an endometrial cancer characterized by the presence of histologically undifferentiated carcinoma. Genomic inactivation of core switch/sucrose nonfermentable (SWI/SNF) complex proteins was recently identified in approximately two-thirds of DDEC/UEC. The aim of this study was to delineate the clinical behavior of SWI/SNF-deficient DDEC/UEC in comparison to SWI/SNF-intact DDEC/UEC. The study cohort consisted of 56 SWI/SNF-deficient DDEC/UEC (2 POLE-mutated), which showed either SMARCA4 (BRG1) loss, ARID1A/1B co-loss, or SMARCB1 (INI1) loss in the undifferentiated tumor, and 26 SWI/SNF-intact DDEC/UEC (4 POLE-mutated). The average age at diagnosis was 61 years for patients with SWI/SNF-deficient tumors and 64 years for SWI/SNF-intact tumors. Mismatch repair (MMR) protein deficiency was seen in 66% of SWI/SNF-deficient and 50% of SWI/SNF-intact tumors. At initial presentation, 55% of patients with SWI/SNF-deficient tumors had extrauterine disease spread in contrast to 38% of patients with SWI/SNF-intact tumors. The 2-year disease specific survival (DSS) for stages I and II disease was 65% for SWI/SNF deficient tumors relative to 100% for SWI/SNF-intact tumors (p = 0.042). For patients with stages III and IV disease, the median survival was 4 months for SWI/SNF-deficient tumors compared to 36 months for SWI/SNF-intact tumors (p = 0.0003). All six patients with POLE-mutated tumors, including one with stage IV SWI/SNF-deficient tumor were alive with no evidence of disease. Among the patients with advanced stage SWI/SNF-deficient tumors, 68% (21 of 31) received adjuvant or neoadjuvant chemotherapy (platinum/taxane-based) and all except the patient with a POLE-mutated tumor (20 of 21) experienced disease progression either during chemotherapy or within 4 months after its completion. These findings show that core SWI/SNF-deficiency defines a highly aggressive group of undifferentiated cancer characterized by rapid disease progression that is refractory to conventional platinum/taxane-based chemotherapy. This underscores the importance of accurate clinical recognition of this aggressive tumor and the need to consider alternative systemic therapy for these tumors.

Clinicopathological significance of multiple molecular features in undifferentiated and dedifferentiated endometrial carcinomas

We investigated the clinicopathological significance of multiple molecular features in undifferentiated and dedifferentiated endometrial carcinomas (UDECs). Eighteen dedifferentiated endometrial carcinomas (DDECs) and three undifferentiated endometrial carcinomas (UECs) were collected. Polymerase-ε exonuclease domain mutations (POLE-EDM) were analysed by Sanger sequencing. SWI/SNF complex subunits, mismatch repair (MMR) proteins, p53, and PD-L1 were evaluated by immunohistochemistry. The SWI/SNF complex was inactivated in half of the UDECs; variably combined with deficient MMR (dMMR), POLE-EDM, or p53 aberrance. Deficiencies in BRG1 and ARID1A were mutually exclusive (p<0.05) in DDECs. ARID1A defects were mostly (8/9) associated with dMMR and typically occurred simultaneously in both endometrioid and dedifferentiated components, whereas BRG1 defects were less frequently (3/7) combined with dMMR and were only observed in dedifferentiated cells. Two-thirds of the UDECs displayed dMMR, mainly caused by the MLH1 promotor methylation. Mutant p53 immunostaining was detected in accordant or subclonal patterns. All three POLE-EDM UDEC patients had stage IA disease with either dMMR or p53 abnormality. Strong positive signals for PD-L1 were mainly detected in dMMR samples. BRG1 defects may likely trigger the progression of dedifferentiation in UDECs by superimposing the pre-existing driver events or by initiating UECs de novo, whereas ARID1A inactivation is subordinate and may likely be secondary to dMMR. The biological behaviours of BRG1-intact UDECs were evaluated according to The Cancer Genome Atlas molecular classification; their driver events require further analysis. Exact molecular subtypes can be helpful for clinical management and treatment decisions for patients with UDEC.

Role of SMARCA4 (BRG1) and SMARCB1 (INI1) in Dedifferentiated Endometrial Carcinoma With Paradoxical Aberrant Expression of MMR in the Well-Differentiated Component: A Case Report and Review of the Literature

INTRODUCTION

Dedifferentiated endometrial carcinoma is an uncommon highly aggressive uterine tumor. It comprises 2 components: a well-differentiated, low-grade epithelial carcinoma and an undifferentiated carcinoma. The undifferentiated carcinoma frequently exhibits rhabdoid cytologic features. Many of these tumors are characterized by an aberrant switch/sucrose non-fermenting (SWI/SNF) complex. They may also exhibit aberrant expression of mismatch repair (MMR) proteins. Together, these play an important role in the pathogenesis and aggressive nature of the tumor.

MATERIAL AND METHODS

We present a case of dedifferentiated endometrial carcinoma in a 63-year-old female showing loss of expression of SWI/SNF-related, matrix-associated, actin-dependent regulator of chromatin, subfamily A, member 4 (SMARCA4/BRG1), and aberrant expression of MMR proteins. We also review the literature starting from the earliest recognition of this entity and the various studies done to explain its molecular pathogenesis and prognostic importance.

RESULTS AND CONCLUSIONS

Recognition of SWI/SNF complex-deficient dedifferentiated endometrial carcinoma is important as these tumors do not respond to platinum-based chemotherapy, and consideration of alternative therapies is often necessary. We also want to emphasize that though most of the studies have found MMR deficiency in the undifferentiated carcinoma component, it may be seen only in the low-grade, well-differentiated component, as observed in this case.

Clinicopathological features of 50 mismatch repair (MMR)-deficient endometrial carcinomas, tested by immunohistochemistry: A single institutional feasibility study, India

There are few comprehensive studies from Asia on clinicopathologic features of mismatch repair (MMR)-deficient endometrial carcinomas, including rarely from our country. One hundred and four cases of endometrial carcinomas were tested for four MMR proteins by immunohistochemistry. Among 50 MMR-deficient (MMRd) tumors(48%), age-range was 27-68 years(median = 53) and tumor size(n = 34) varied from 1.2-10 cm(average = 4.6). Lower uterine segment(LUS) was involved in 21/31 cases(67.7%). Histopathologically, all cases were endometrioid adenocarcinomas(EMACs), of FIGO grade 2(low-grade)(18 cases) and 3(high-grade)(32 cases), displaying de-differentiated, undifferentiated and lymphoepithelioma(LE)-like patterns, in 24 cases(48%). Tumor infiltration ≥ half of myometrium was seen in 30/44 cases (68.1%); lymphovascular emboli in 19/43 cases(44.1%); and lymph node metastasis in 7/22(31.8%) cases. Uncommonly, clear cell component(n = 2) and focal neuroendocrine differentiation (n = 2) were observed. Immunohistochemically, tumor cells showed paired loss of MLH1 and PMS2 in 33(66%) and MSH2 and MSH6 in 14(28%) cases, along with loss of MSH2 and PMS2, in two and a single case, respectively. Nine patients(18%) were treated for another cancer and 9/33(27.2%) disclosed familial history of cancer. MSH2 was the most frequently lost MMR protein in those cases. Additionally, tumor cells displayed ER positivity in 41/50 cases(82%), PR in 38/41cases(92.6%) and wild-type p53 staining in 24/28 cases(85.7%). Tumor with LE-pattern showed PDLI immunoexpression. Certain clinicopathologic features suggestive for MMRd associated ECs, such as relatively large-sized tumors, involving LUS; especially high-grade, infiltrative EMACs, with undifferentiated/de-differentiated, and LE-like patterns; showing deep muscle invasion, frequent PR immunoexpression and invariably, wild-type p53 immunostaining can be useful in screening cases of Lynch syndrome. This constitutes the first report on these tumors from our country.

Dedifferentiated endometrioid adenocarcinoma of the uterus: A case series and review of literature

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Dedifferentiated endometrioid adenocarcinoma is a rare aggressive subtype of endometrial cancer.

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Patients tend to present at a later stage and have early recurrences.

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Proportion of DEAC in endometrial cancer may affect outcome.

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Further research should focus on PD-L1 expression and the use immunotherapy.

Introduction Dedifferentiated endometrioid adenocarcinoma (DEAC) was first described in 2007. However, it has only been recognised as a distinct subtype of endometrioid adenocarcinoma in the last 1–2 years. DEAC is a more aggressive histological subtype and carries a poorer prognosis. Patients with DEAC tend to present with advanced disease compared the other endometrioid adenocarcinomas. Methodology The study is a retrospective review of patients with DEAC diagnosed in two institutions in Singapore between January 2012 and October 2017. Results 7 patients were diagnosed with DEAC. The mean age was 56.4 years. All patients presented with either abnormal uterine bleeding or post menopausal bleeding. Out of the 7 patients, one was diagnosed with Stage 2 disease, 5 were diagnosed with Stage 3 disease and 1 was diagnosed with Stage 4 disease. One patient had neoadjuvant chemotherapy, followed by surgery, and completion chemotherapy post surgery. The other 6 patients (87.5%) underwent primary debulking surgery. Out of these 6 patients, 5 patients had adjuvant chemotherapy post surgery and one patient had both adjuvant chemotherapy and radiotherapy. Lymphovascular invasion was found in 71.4% of the cases. Conclusion DEAC is a more aggressive histological subtype of endometrioid adenocarcinomas. Better awareness of this condition can lead to proper diagnosis and treatment.