Clear cell adenocarcinoma of the endometrium is a biologically distinct entity from endometrioid adenocarcinoma

Clear Cell Carcinoma of the Endometrium: Evaluation of Prognostic Parameters in 27 Cases

Objective

Clear cell carcinoma (CCC) of the endometrium is an uncommon yet aggressive tumor. Few cohort studies are reporting the overall survival time of CCC patients. This study aimed to retrospectively analyze the clinicopathologic features, molecular characteristics and survival data of 27 endometrial CCC patients to improve the understanding of CCC.

Methods

The clinicopathologic features, molecular characteristics and survival data total of 27 CCC patients admitted to the BBMU affiliated hospital (Anhui, China) between January 2005 and December 2018 were retrospectively analyzed. Kaplan-Meier method was used to analyze the prognosis-related factors.

Results

The median age of the patients was 60 years (range; 39 to 81 years). The average tumor size was 3.8 cm (range; 0.8 to 13.0cm). Myometrial infiltration greater than 50% was reported in 55.6% of the patients, while the Ki-67 index greater than 50% was reported in 70.4% of the patients. The patients’ FIGO (2009) surgical stages were as follows: 18 I, 3 II, 4 III, and 2 IV. Besides, 7 (25.6%) patients had lymphovascular invasion, 3 (11.1%) patients with distant metastasis, including 1 patient with bone metastasis, and 2 with liver metastasis. Adjuvant treatment included 7 with chemotherapy alone, 9 with radiotherapy alone, and 9 with both radiotherapy and chemotherapy. The median overall survival time from the time of CCC diagnosis was 56 months. ER and PR showed negative expression and P16 showed patchy immunostaining. 18 (63%) cases showed Napsin A positive expression. Loss of MSH2, MSH6 and PTEN were seen in 5, 4 and 7 cases respectively. All cases showed HER-2/nue negative expression.

Conclusion

CCC is a rare and invasive tumor. Age of diagnosis, FIGO stage, tumor size, myometrial infiltration, lymphovascular invasion, distant metastasis, Ki-67 index and P53 expression are important indicators to evaluate patient’s prognosis (P = 0.048, P < 0.001, P = 0.016, P = 0.043, P = 0.001, P < 0.001, P = 0.026, and P = 0.007, respectively). CCC has a worse prognosis than endometrioid carcinoma (P = 0.002), and there is no significant difference when compared with uterine papillary serous carcinoma (P = 0.155).

A clear cancer cell line (150057) derived from human endometrial carcinoma harbors two novel mutations

BACKGROUND

Cell lines are extremely useful for both basic and clinical research. Thus, establishing endometrial cancer cell lines with malignant histology is important. This study aimed to extensively characterize an endometrial clear cell carcinoma cell line.

METHODS

This cell line, named 150,057, was derived from the endometrial clear cell cancer of a 63-year-old woman. The morphology, chromosomes, chemosensitivity, tumor markers, xenotransplantation characteristics, and cancer-related genes of the cell line were characterized.

RESULTS

This cell line exhibited adequate growth, being passaged more than 70 times. The morphology of the cells was polygonal with a cobblestone-like appearance. Karyotyping of the cell line revealed a hypodiploid chromosomal number. 150057 cells expressed CA19-9 and CA125. The cell line was sensitive to doxorubicin, paclitaxel, carboplatin, and cisplatin. After the cells were transplanted into the subcutaneous region of non-obese diabetic-severe combined immunodeficiency mice, they generated xenograft tumors with similar histology as the original tumor. A total of 59 somatic nucleotide mutations were identified in 25 of the 53 examined tumor suppressor genes and oncogenes. Two novel mutations were found in FGFR3 and ARID1A.

CONCLUSION

We established and characterized an endometrial clear cell carcinoma cell line that may be useful in carcinogenesis and treatment research for endometrial cancer.

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.

Screening for hereditary cancers in patients with endometrial cancer reveals a high frequency of germline mutations in cancer predisposition genes

As inherited genetic alterations are important etiological factors causing endometrial cancer (EC), our study aimed to outline the ethnic-related prevalence and the associated clinical and biological characteristics of germline mutations in cancer predisposition genes in Chinese EC patients. One hundred ninety-eight Chinese EC patients were screened for germline mutations in a panel of cancer susceptibility genes using next-generation sequencing combined with multiplex ligation-dependent probe amplification. First, we found that among patients under 50 years of age, 26% (18/69) carried germline genetic mutations, all involving mismatch repair (MMR) genes except for one mutation affecting BRCA1. Second, when we focused on Lynch syndrome (LS) with additional selected patients, 45 were identified to carry pathogenic mutations in MMR genes, with a higher frequency found in MSH2 and MSH6. We found that age at onset, personal and familial history together with immunohistochemical assay results were the most useful criteria for the diagnosis of LS although limitations in routine practice and the sensitivity and specificity of each parameter should be taken into account. One pathogenic mutation in the PALB2 gene was detected in a patient with no breast cancer in her family. Interestingly, we identified a family carrying pathogenic variant in both PMS2 and BRCA1 genes with distinct clinical phenotypes. Multigene panel testing should be recommended to patients based on their clinical information and tumor phenotype. Our study also showed the genetic complexity in EC, which requires further investigations.

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.

The ARID1A, p53 and ß-Catenin statuses are strong prognosticators in clear cell and endometrioid carcinoma of the ovary and the endometrium

Aim

The objective of this study was to evaluate the prognostic value of ARID1A, p53, p21, p16 and ß-Catenin in endometrioid and clear cell ovarian and endometrial carcinomas.

Materials and methods

97 tumors were available for analysis of ARID1A, p53, p21, p16 and ß-Catenin with the techniques of tissue microarray and immunohistochemistry. 32 were ovarian carcinomas and 65 were endometrial carcinomas.

Results

Endometrioid ovarian carcinomas showed negative staining for ARID1A (a) and p21 (b), aberrant expression of p53 (c) and p16 (d) and ß-Catenin positive nuclear expression (e) respectively in 19% (a), 100% (b), 28.6% (c), 52.4% (d) and 4.8% (e) of all cases. In the group of clear cell ovarian carcinomas it was 63.6% (a), 100% (b), 81.8% (c), 54.5% (d) and 0% (e). For endometrioid uterine carcinomas it was 75.7% (a), 94.9% (b), 30.5% (c), 52.1% (d) and 6.8% (e) and for clear cell uterine carcinomas it was 8.6% (a), 100% (b), 50% (c), 100% (d) and 0% (e). Survival analysis showed that negative expression of ARID1A, p53 aberrant expression and ß-Catenin nuclear positive staining are independent negative prognosticators in both, clear cell and endometrioid carcinoma, regardless of ovarian or uterine origin. Cox-Regression analysis showed them again as negative prognostic factors. Furthermore, we found a significant correlation between ARID1A and ß-Catenin expression in endometrioid uterine tumors.

Conclusion

The analyzed gynaecological carcinoma showed a distinct expression scheme of proteins that are associated with tumor suppression. We may conclude that ARID1A, p53 and ß-Catenin are the strongest prognostic factors by analyzing a subgroup of tumor suppressor genes in clear cell and endometrioid subtypes of ovarian and endometrial cancer and may be used along with traditional morphological and clinical characteristics for prognosis.

Gynecologic Cancer InterGroup (GCIG) Consensus Review for Clear Cell Carcinoma of the Uterine Corpus and Cervix

Abstract

Clear cell carcinomas of the uterine corpus and cervix are rare gynecological cancers with limited information regarding the pathogenesis and biology. At present, the approach to management is the same as for patients with the more common histological subtypes of endometrioid endometrial cancer and adenocarcinoma of the cervix. Surgical resection is the standard treatment for patients with early-stage disease, but there is no evidence-based approach to direct the management of patients with more advanced-stage disease at presentation or with recurrent disease. We review the epidemiology, pathology, and what is known about both uterine corpus and cervical clear cell cancers and make management recommendations.

Clear cell carcinoma of ovary and uterus

Clear cell carcinomas of the female genital tract are rare tumours with a fearsome reputation for having poor responses to conventional platinum-based chemotherapy and poor prognosis. However, it is now clear that early-stage ovarian clear cell carcinoma has an excellent prognosis and may not require any adjuvant therapy. In addition, radiotherapy may also have a key role to play in adjuvant management of clear cell tumours. Identification of patients who truly do not need adjuvant chemotherapy is important. The past 3 years has seen a significant improvement in our understanding of clear cell carcinoma biology-in particular, the role of mutations in the chromatin remodelling gene ARID1A as key drivers that are common to clear cell carcinomas of ovarian and endometrial origin. Moreover, gynaecological clear cell carcinomas appear to share many features with renal clear cell tumours, suggesting a common pathogenesis. This raises the possibility of clinical trials that include patients with clear cell tumours from different organs of origin. Dissecting the role of disordered chromatin organisation in clear cell carcinoma pathogenesis is a key priority. Finally, the role of endometriosis and the attendant chronic inflammation are recognised. The inflammatory cytokine interleukin-6 appears to play a key role in clear cell carcinoma biology and is an excellent potential therapeutic target.

The clinicopathologic significance of p53 and BAF-250a (ARID1A) expression in clear cell carcinoma of the endometrium

TP53 mutation (and associated p53 protein overexpression) is probably a negative prognostic marker in endometrial cancers, but its relevance in the rarer histologic subtypes, including clear cell carcinomas, has not been delineated. Preclinical studies suggest functional interactions between p53 and the BAF250a protein, the product of a tumor suppressor gene ARID1A (adenine-thymine (AT)-rich interactive domain containing protein 1A) that is frequently mutated in ovarian clear cell carcinoma. In this study, we evaluated the significance of p53 and BAF250a expression, as assessed by immunohistochemistry, in a group of 50 endometrial clear cell carcinomas. Of 50 cases, 17 (34%) were p53+, and the remaining 33 cases had a p53 wild-type (p53-wt) immunophenotype. Of the 11 relapses/recurrences in the entire data set, 73% were in the p53+ group (P=0.008). On univariate analyses, the median overall survival for the p53-wt patients (83 months) was longer than the p53+ patients (63 months) (P=0.07), and the median progression-free survival for the p53-wt group (88 months) was significantly longer than the p53+ group (56 months) (P=0.01). On multivariate analyses, p53 expression was not associated with reduced overall or progression-free survival. In addition, p53 status was not significantly associated with pathologic stage or morphologic patterns. Of the 50 cases, 10 (20%) showed a complete loss of BAF250a expression. There was no significant correlation between p53 and BAF250a expression. The p53+/BAF250a-, p53+/BAF250a+, p53-wt/BAF250a+ and p53-wt/BAF250a- composite immunophenotypes were identified in 8%, 26%, 54% and 12% of cases, respectively, and neither loss of BAF250a expression nor composite p53/BAF250a expression patterns were associated with reduced overall or progression-free survival. In conclusion, a significant subset of CCC express p53, and these cases are apparently not definable by their morphologic features. P53 expression may be a negative prognostic factor in this histotype, and warrants additional studies. Loss of BAF250a expression has no prognostic significance in endometrial clear cell carcinomas.

Anthracycline-based chemotherapy in metastatic endometrial carcinoma: an update

The purpose of this review is to analyze clinical evidence about the activity and efficacy of anthracycline-based chemotherapy in metastatic endometrial cancer and to identify the most important preclinical findings that would address future clinical trials. A literature search of published studies was undertaken. Studies were selected by predefined criteria. Clinical trials and preclinical studies were analyzed. The search identified eight phase 3 and 13 phase 2 clinical trials of patients with metastatic endometrial carcinoma treated with an anthracycline-based regimen. The planned dose intensity of the anthracycline had no effect on response rates and survival. Survival increased for patients with a good performance status, and sometimes the duration of responses to anthracycline monotherapy can be very long-lasting. The major findings of anthracycline resistance in preclinical models are reported. Possible future biomarkers targeting mechanisms of anthracycline resistance are suggested, and efforts to define a molecular classification of endometrial cancer are desirable.

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.

Endometrial carcinomas: a review emphasizing overlapping and distinctive morphological and immunohistochemical features

This review focuses on the most common diagnostic pitfalls and helpful morphologic and immunohistochemical markers in the differential diagnosis between the different subtypes of endometrial carcinomas, including: (1) endometrioid versus serous glandular carcinoma, (2) papillary endometrioid (not otherwise specified, villoglandular and nonvillous variants) versus serous carcinoma, (3) endometrioid carcinoma with spindle cells, hyalinization, and heterologous components versus malignant mixed müllerian tumor, (4) high-grade endometrioid versus serous carcinoma, (5) high-grade endometrioid carcinoma versus dedifferentiated or undifferentiated carcinoma, (6) endometrioid carcinoma with clear cells versus clear cell carcinoma, (7) clear cell versus serous carcinoma, (8) undifferentiated versus neuroendocrine carcinoma, (9) carcinoma of mixed cell types versus carcinoma with ambiguous features or variant morphology, (10) Lynch syndrome-related endometrial carcinomas, (11) high-grade or undifferentiated carcinoma versus nonepithelial uterine tumors. As carcinomas in the endometrium are not always primary, this review also discusses the differential diagnosis between endometrial carcinomas and other gynecological malignancies such as endocervical (glandular) and ovarian/peritoneal serous carcinoma, as well as with extra-gynecologic metastases (mainly breast and colon).

Endometrial clear cell adenocarcinoma diagnosed by endometrial cytological examination: two cases report

In contrast to endometrioid endometrial adenocarcinoma (EA), endometrial clear cell adenocarcinoma (ECCA) is rare and shows a clinically aggressive potential, resulting in a poor prognosis. Therefore, the early diagnosis of ECCA is crucial for the treatment of patients bearing the tumor. Here, we report two cases of ECCA diagnosed by cytological examination. Case 1 was a 67-year-old female, while case 2 was a 68-year-old female. In both cases, tumors of the corpus uteri were identified, and they were diagnosed as ECCA on cytological examination with specimens derived from endometrial brushing. The diagnosis was confirmed by the histological examination of the surgical specimens.

High-Grade Endometrial Carcinomas

High-grade endometrial carcinomas are a heterogeneous group of clinically aggressive tumors. They include FIGO grade 3 endometrioid carcinoma, serous carcinoma, clear cell carcinoma, undifferentiated carcinoma, and malignant mixed Müllerian tumor (MMMT). Epidemiologic, genetic, biologic prognostic and morphologic differences between these entities are striking in prototypic cases, yet substantial overlap exists and diagnostic criteria and therapeutic approaches that account for the group's diversity are currently insufficient. FIGO grade 3 endometrioid carcinoma demonstrates solid, trabecular or nested growth and may resemble poorly differentiated squamous cell carcinoma. Endometrioid glandular differentiation is usually focally present. Serous carcinoma usually displays papillary architecture but glandular and solid patterns may predominate. Tumor cells typically display diffuse and severe atypia. Clear cell carcinoma should be diagnosed by recognizing characteristic papillary or tubulocystic architecture with cuboidal tumor cells showing atypical but uniform nuclei. Cells with clear cytoplasm are frequently but not always present. On the other hand, clear cells may be encountered in endometrioid and serous carcinomas. Immunohistochemical stains for p53, p16, ER, PR, mib-1, hepatocyte nuclear factor 1β and pan-cytokeratin can be helpful in classifying these high-grade carcinomas. They should be used in concert with thorough morphologic examination, as part of a rational panel of markers and only in specific circumstances. Although these tumors may appear clinically and even morphologically similar, demographic and epidemiologic features as well as patterns of spread and treatment modalities differ.

Aristolochic acid-induced cell cycle G1 arrest in human urothelium SV-HUC-1 cells

Aristolochic acid (AA) has been implicated in urothelial carcinoma in humans. To evaluate the impact of AA on the human urinary tract epithelium cells, a study of SV-HUC-1 cells cultured with mixture of AA (AAM; 41% AA I, 56% AA II) was conducted. Cell viability was assayed in cultures exposed to 0.0125-0.2mM AAM for 1, 3, and 5 days, a concentration-dependent inhibition on the growth of SV-HUC-1 cells was demonstrated. Cell cycle distribution determined by flow cytometry revealed an accumulation of cells in the G0/G1 phase (from 37.6% to 49.2%). Regarding the cell cycle control proteins, the levels of p53, p21 and p27 increased in a concentration-dependent manner. Immunoprecipitation demonstrated a decrease in the formation of cyclin E/cdk2 complex, but not cyclin D1/cdk4 complex, which leads to an increase in the free form of cdk2. Additionally, a decrease in the phospho-Rb correlates with an increase in Rb/E2F-1 complex which prevents the release of E2F transcription factor, thus preventing the transcription of the genes required for cell proliferation. Our results provide evidence that AAM induce cell cycle arrest in SV-HUC-1 cells. Whether this cell cycle block is associated with AA-related human urothelial carcinoma requires further study to clarify.