Updates in diagnostic immunohistochemistry in endometrial carcinoma

Correlative Assessment of p53 Immunostaining Patterns and TP53 Mutation Status by Next-Generation Sequencing in High-Grade Endometrial Carcinomas

TP53 mutations are frequently identified in the copy number-high molecular subgroup of endometrial carcinomas (ECs). P53 immunohistochemistry (IHC) is a widely used surrogate marker reflecting the mutational status of TP53 , and recent reports have shown ~95% concordance between the two methods in ECs. While these results are promising, studies evaluating the correlation between different p53 IHC staining patterns and comprehensive next-generation sequencing results are still limited. We compared the p53 IHC staining patterns, scored as wild-type, diffuse nuclear overexpression, null/complete absence, and cytoplasmic, to next-generation sequencing results reported by FoundationOneCDx in 43 high-grade ECs: 20 serous ECs, 9 mixed ECs with a serous component, 4 carcinosarcomas with a serous component, and 10 grade 3 endometrioid ECs. The concordance of p53 IHC and TP53 mutation status was 100% (43/43) overall, including 100% (33/33) concordance in tumors with a serous component and 100% (10/10) in endometrioid ECs. Among the 35 tumors with aberrant p53 expression the most commonly observed pattern was diffuse nuclear overexpression seen in 69% (24/35), followed by cytoplasmic staining in 17% (6/35), and complete absence of staining (null) in 14% (5/35) of tumors. Of the 6 tumors with cytoplasmic staining, 4 corresponded to missense mutations within the DNA binding domain (V157F in 2 tumors, and S127P and R280S, in 2 tumor each), while 2 corresponded to nonsense mutations in the tetramerization domain (p.E339*). Our results further support that p53 IHC can serve as an accurate predictor of TP53 alterations in ECs to aid the molecular-based tumor classification and the distinction between tumor histotypes, both of which play an important role in the assessment of clinical prognosis and therapeutic decision making. In addition, our data suggest, that the type and position of TP53 mutation may not directly correlate with the observed p53 IHC pattern in all tumors, and that there may be alternative mechanisms for cytoplasmic localization (other than mutations involving the nuclear localization domain), possibly due to conformational changes or posttranslational modifications of the aberrant p53 protein.

In the Model Cell Lines of Moderately and Poorly Differentiated Endometrial Carcinoma, Estrogens Can Be Formed via the Sulfatase Pathway

Endometrial cancer (EC) is the most common gynecological malignancy in resource-abundant countries. The majority of EC cases are estrogen dependent but the mechanisms of estrogen biosynthesis and oxidative metabolism and estrogen action are not completely understood. Here, we evaluated formation of estrogens in models of moderately and poorly differentiated EC: RL95-2 and KLE cells, respectively. Results revealed high expression of estrone-sulfate (E1-S) transporters (SLCO1A2, SLCO1B3, SLCO1C1, SLCO3A1, SLC10A6, SLC22A9), and increased E1-S uptake in KLE vs RL95-2 cells. In RL95-2 cells, higher levels of sulfatase and better metabolism of E1-S to E1 were confirmed compared to KLE cells. In KLE cells, disturbed balance in expression of HSD17B genes led to enhanced activation of E1 to E2, compared to RL95-2 cells. Additionally, increased CYP1B1 expression and down-regulation of genes encoding phase II metabolic enzymes: COMT, NQO1, NQO2, and GSTP1 suggested decreased detoxification of carcinogenic metabolites in KLE cells. Results indicate that in model cell lines of moderately and poorly differentiated EC, estrogens can be formed via the sulfatase pathway.

Survival implication of lymphadenectomy in patients surgically treated for apparent early-stage uterine serous carcinoma

OBJECTIVE

Uterine serous carcinoma (USC) is a rare highly aggressive disease. In the present study, we aimed to investigate the survival implication of the systematic lymphadenectomy in patients who underwent surgery for apparent early-stage USC.

METHODS

Consecutive patients with apparent early-stage USC surgically treated at six Italian referral cancer centers were analyzed. A comparison was made between patients who underwent retroperitoneal staging including at least pelvic lymphadenectomy "LND" vs. those who underwent hysterectomy alone "NO-LND". Baseline, surgical and oncological outcomes were analyzed. Kaplan- Meier curves were calculated for disease-free survival (DFS) and disease-specific survival (DSS). Associations were evaluated with Cox proportional hazard regression and summarized using hazard ratio (HR).

RESULTS

One hundred forty patients were analyzed, 106 LND and 34 NO-LND. NO-LND group (compared to LND group) included older patients (median age, 73 vs.67 years) and with higher comorbidities (median Charlson Comorbidity Index, 6 vs. 5) (p<0.001). No differences in terms of recurrence rate (LND vs. NO-LND, 33.1% vs. 41.4%; p=0.240) were observed. At Cox regression analysis lymphadenectomy did not significantly influence DFS (HR=0.59; 95% confidence interval [CI]=0.32-1.08; p=0.09), and DSS (HR=0.14; 95% CI=0.02-1.21; multivariable analysis p=0.07). Positive node was independently associated with worse DFS (HR=6.22; 95% CI=3.08-12.60; p<0.001) and DSS (HR=5.51; 95% CI=2.31-13.10; p<0.001), while adjuvant chemotherapy was associated with improved DFS (HR=0.38; 95% CI=0.17-0.86; p=0.02) and age was independently associated with worse DSS (HR=1.07; 95% CI=1.02-1.13; p<0.001).

CONCLUSIONS

Although lymphadenectomy did not show survival benefits in patients who underwent surgery for apparent early-stage USC, the presence of lymph node metastasis was the main adverse prognostic factors, supporting the prognostic role of the retroperitoneal staging also in this histological subtype.

Metabolomics for Diagnosis and Prognosis of Uterine Diseases? A Systematic Review

This systematic review analyses the contribution of metabolomics to the identification of diagnostic and prognostic biomarkers for uterine diseases. These diseases are diagnosed invasively, which entails delayed treatment and a worse clinical outcome. New options for diagnosis and prognosis are needed. PubMed, OVID, and Scopus were searched for research papers on metabolomics in physiological fluids and tissues from patients with uterine diseases. The search identified 484 records. Based on inclusion and exclusion criteria, 44 studies were included into the review. Relevant data were extracted following the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analysis) checklist and quality was assessed using the QUADOMICS tool. The selected metabolomics studies analysed plasma, serum, urine, peritoneal, endometrial, and cervico-vaginal fluid, ectopic/eutopic endometrium, and cervical tissue. In endometriosis, diagnostic models discriminated patients from healthy and infertile controls. In cervical cancer, diagnostic algorithms discriminated patients from controls, patients with good/bad prognosis, and with/without response to chemotherapy. In endometrial cancer, several models stratified patients from controls and recurrent from non-recurrent patients. Metabolomics is valuable for constructing diagnostic models. However, the majority of studies were in the discovery phase and require additional research to select reliable biomarkers for validation and translation into clinical practice. This review identifies bottlenecks that currently prevent the translation of these findings into clinical practice.

SWATH-MS Analysis of FFPE Tissues Identifies Stathmin as a Potential Marker of Endometrial Cancer in Patients Exposed to Tamoxifen

A specific form of endometrial cancer (EC) can develop in breast cancer patients previously treated with tamoxifen (ET), an antagonist of estrogen receptor (ER) that inhibits proliferation of ER positive breast cancer. ET tumors have a different phenotype than endometrial tumors, which typically develop de novo without previous exposure to tamoxifen (EN). Here we aimed to identify specific protein markers that could serve as specific molecular targets in either phenotype. A set of total 45 formalin-fixed paraffin-embedded (FFPE) endometrial tumor tissues and adjacent myometrium tissue samples were analyzed using LC-MS/MS in SWATH-MS mode. We found that calcyphosin (CAPS) levels were elevated in EN tumors compared to ET tumors. The higher CAPS level in EC tissue invading to myometrium supports its relationship to EC aggressiveness. Further, stathmin (STMN1) levels were found significantly elevated in ET versus EN tumors and significantly associated with patient survival. This finding connects elevated levels of this cell cycle regulating, proliferation-associated protein with tamoxifen exposure. In summary, using SWATH-MS we show that CAPS and STMN1 should be recognized as clinicopathologically different EC markers of which STMN1 is specifically connected with a previous tamoxifen exposition.

High-Grade Endometrial Carcinomas: Classification with Molecular Insights

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

A Selected Immunohistochemical Panel Aids in Differential Diagnosis and Prognostic Stratification of Subtypes of High-grade Endometrial Carcinoma: A Clinicopathologic and Immunohistochemical Study at a Single Institution

This study aimed to investigate whether a selected immunohistochemical panel (estrogen receptor, p53, ARID1A, PPP2R1A, HNF-1β) could contribute to the diagnostic process of high-grade endometrial carcinomas (HG-ECs). We also aimed to analyze the correlation of these immunohistochemical results with several morphologic variables and survival data. After revising the diagnosis of 78 HG-ECs, immunohistochemical analysis was performed for each case. After immunohistochemical analysis, a specific diagnosis of prototypic HG-EC was established in most of the cases that were uncertain due to morphologic ambiguity. In the univariate analysis, older patient age, type II morphology, undifferentiated carcinoma and carcinosarcoma type of histology, altered p53 immunostaining, strong membranous staining of PPP2R1A, presence of lymphovascular invasion in serous carcinoma, and microcystic, elongated, and fragmented-type infiltration pattern in endometrioid carcinoma were significantly related to poor prognosis. In the multivariate analysis, only older patient age and carcinosarcoma or undifferentiated/dedifferentiated carcinoma type histology were found to be significantly poor prognostic factors (P=0.011), whereas advanced FIGO stage and type II histology were found to be correlated with poor prognosis, but did not reach statistical significance. We suggest that immunohistochemistry should be used in the differential diagnosis of HG-ECs, especially those with ambiguous morphology. Markers used in this study made a valuable contribution to the diagnostic process as well as prediction of prognosis.

Comparative Use of Napsin A and Glypican 3 to Distinguish Endometrial Clear Cell from Serous and Endometrioid Carcinomas

OBJECTIVE

Diagnosis of endometrial clear cell carcinomas is difficult owing to the low reproducibility of histological cell type in high-grade endometrial cancers. Recently, immunoreactivity for napsin A and glypican 3 has been reported in clear cell cancers. We sought to evaluate the use of napsin A and glypican 3 staining to distinguish clear cell carcinoma from other high-grade endometrial cancers.

METHODS/MATERIALS

Twenty cases of pure and mixed endometrial clear cell carcinoma were extracted from the 2000-2014 archival material in the Departments of Obstetrics & Gynecology and Pathology at Montefiore Medical Center and compared to serous and grade 3 endometrioid controls. Representative sections were stained with monoclonal antibodies to napsin A and glypican 3. Immunostains were independently reviewed by 2 pathologists to assess frequency and pattern of staining. Charts were reviewed for clinicopathologic and treatment data.

RESULTS

Granular cytoplasmic positivity for napsin A was observed in 70% of endometrial clear cell carcinomas; only 25% showed cytoplasmic or membranous glypican 3 positivity. No serous or high-grade endometrioid tumors stained for either marker. No cases of clear cell carcinoma that stained negative for napsin A stained positive for glypican 3. No difference in the immunohistochemical profile was found between pure and mixed clear cell carcinomas and between early- and advanced-stage clear cell carcinomas.

CONCLUSIONS

Napsin A is a more sensitive marker for endometrial clear cell carcinoma than glypican 3. In histologically ambiguous cases, napsin A and glypican 3 may help distinguish clear cell carcinoma from other high-grade histologies. Further investigation of endometrial clear cell carcinoma is needed to identify additional diagnostic tools for this rare histology. Correlation of a unique immunohistochemical profile and clinical outcomes is necessary.

Immunohistochemical expression of hormone receptors, Ki-67, endoglin (CD105), claudins 3 and 4, MMP-2 and -9 in endometrial polyps and endometrial cancer type I

Objective

The aim of this study was to investigate the malignant potential of endometrial polyps (EP) by assessing the immunoexpressions of both estrogen receptor (ER) and progesterone receptor (PR), Ki-67 cell proliferation index, neovascularization network (endoglin – CD105), cellular adhesion molecules (claudins 3 and 4), and extracellular matrix proteins (MMP-2 and -9) in both EP and endometrioid adenocarcinoma (type I) in comparison with the normal endometrium.

Study design

This is a cross-sectional comparative study. Patients were identified from the database of Botucatu Medical School, São Paulo State University (BMS-UNESP) Clinical Pathology Laboratory.

Setting

The study was conducted using a convenience sample of patients attending the Sectors of Gynecologic Endoscopy and Family Planning and Gynecologic Oncology of the Department of Gynecology and Obstetrics of BMS-UNESP, Brazil.

Patients

A total of 90 women were allocated into the following three groups: EP without atypia (EP, n=30), endometrioid endometrial cancer (EC, n=30), and normal endometrium (control, n=30).

Methods

Epidemiological and clinical data were obtained by reviewing medical records. Adenocarcinoma and control cases were assessed using the tissue microarray technique. The immunoexpressions of ER, PR, Ki-67, CD105, claudins 3 and 4, and MMP-2 and -9 were assessed in paraffin blocks containing sections of the largest polyploid lesion fragment and tissue microarray recipient blocks.

Major results

Compared to the control group, significant differences in the expression of ER (P<0.001), PR (P<0.05), Ki-67 (P<0.001), CD105 (P<0.001), and claudin 3 (P<0.001) were observed in EP and EC. No significant differences were found between EP and EC (P≥0.05). MMP-2 and -9 expression were nearly absent in all groups.

Conclusion

The malignant potential of EP could not be determined through the immunohistochemical parameters used in this study. No MMP-2 or -9 expression was observed in any endometrial tissue sample. Further studies are necessary for a better understanding of the biomolecular mechanisms underlying endometrial carcinogenesis.

Are the uterine serous carcinomas underdiagnosed? Histomorphologic and immunohistochemical correlates and clinical follow up in high-grade endometrial carcinomas initially diagnosed as high-grade endometrioid carcinoma

Histologic subclassification of high-grade endometrial carcinomas can sometimes be a diagnostic challenge when based on histomorphology alone. Here we utilized immunohistochemical markers to determine the immunophenotype in histologically ambiguous high-grade endometrial carcinomas that were initially diagnosed as pure or mixed high-grade endometrioid carcinoma, aiming to determine the utility of selected immunohistochemical panel in accurate classification of these distinct tumor types, while correlating these findings with the clinical outcome. A total of 43 high-grade endometrial carcinoma cases initially classified as pure high-grade endometrioid carcinoma (n=32), mixed high-grade endometrioid carcinoma/serous carcinoma (n=9) and mixed high-grade endometrioid carcinoma/clear cell carcinoma (n=2) were retrospectively stained with a panel of immunostains, including antibodies for p53, p16, estrogen receptor, and mammaglobin. Clinical follow-up data were obtained, and stage-to-stage disease outcomes were compared for different tumor types. Based on aberrant staining for p53 and p16, 17/43 (40%) of the high-grade endometrial carcinoma cases initially diagnosed as high-grade endometrioid carcinoma were re-classified as serous carcinoma. All 17 cases showed negative staining for mammaglobin, while estrogen receptor was positive in only 6 (35%) cases. The remaining 26 cases of high-grade endometrioid carcinoma showed wild-type staining for p53 in 25 (96%) cases, patchy staining for p16 in 20 (77%) cases, and were positive for mammaglobin and estrogen receptor in 8 (31%) and 19 (73%) cases, respectively, thus the initial diagnosis of high-grade endometrioid carcinoma was confirmed in these cases. In addition, the patients with re-classified serous carcinoma had advanced clinical stages at diagnosis and poorer overall survival on clinical follow-up compared to that of the remaining 26 high-grade endometrioid carcinoma cases. These results indicate that selected immunohistochemical panel, including p53, p16, and mammaglobin can be helpful in reaching accurate diagnosis in cases of histomorphologically ambiguous endometrial carcinomas, and can assist in providing guidance for appropriate therapeutic options for the patients.

Molecular insights into the classification of high-grade endometrial carcinoma

Endometrial carcinoma, which is associated with a mortality rate of approximately 20%, is the most common gynecological malignancy in the Western world. It is a heterogeneous disease, with multiple histotypes, each constituting a different disease entity. However, interobserver diagnostic agreement is suboptimal, particularly among the most lethal histotypes. Most recent data also indicate that histotype assignment is not independently associated with survival, while in contrast, clinicopathological risk stratification and genomic classification are significantly prognostic. Recent work has shown that there are four molecular subgroups of endometrioid carcinomas instead of the two types proposed by Bokhman in the 1970s. Carcinomas with polymerase E (POLE) exonuclease domain hotspot mutations are highly prognostically favourable; those with copy-number alterations and TP53 mutations are highly aggressive; and microsatellite unstable and 'copy-number low' endometrioid carcinomas are associated with intermediate prognoses. This review summarises the genetic foundations of the various histotypes of endometrial carcinoma and synthesises this information in the form of algorithms, or classifiers, that recapitulate genomic classification that is not only prognostic, but also potentially diagnostic and therapeutically predictive. A review of Lynch syndrome and Lynch-like syndrome is also provided.

Diagnostic immunohistochemistry in gynaecological neoplasia: a brief survey of the most common scenarios

Immunohistochemistry is a valuable adjunct in routine gynaecological pathology. The molecular revolution has redesigned knowledge of gynaecological cancers and refined histological classification. The direct consequence has been the progressive introduction of new immunostainings for diagnostic and classification purposes. Hence, we review the routine diagnostic use of immunohistochemistry in the field of gynaecological neoplasia. We reviewed the immunomarkers useful in gynaecological pathology according to literature revision, our personal experience and research findings. We discuss the application of immunohistochemistry to reach the most accurate diagnosis in morphologically equivocal cases of gynaecological pathology and present the appropriate panel of immunomarkers in the most common scenarios of gynaecological pathology. This short review provides an updated overview of the essential immunohistochemical markers currently used in the diagnostics of gynaecological malignancies along with their molecular rationale.

TP53 Mutational Spectrum in Endometrioid and Serous Endometrial Cancers

Endometrial carcinomas (ECs) are heterogeneous at the genetic level. Although TP53 mutations are highly recurrent in serous endometrial carcinomas (SECs), these are also present in a subset of endometrioid endometrial carcinomas (EECs). Here, we sought to define the frequency, pattern, distribution, and type of TP53 somatic mutations in ECs by performing a reanalysis of the publicly available data from The Cancer Genome Atlas (TCGA). A total of 228 EECs (n=186) and SECs (n=42) from the TCGA data set, for which an integrated genomic characterization was performed, were interrogated for the presence and type of TP53 mutations, and for mutations in genes frequently mutated in ECs. TP53 mutations were found in 15% of EECs and 88% of SECs, and in 91% of copy-number-high and 35% of polymerase (DNA directed), epsilon, catalytic subunit (POLE) integrative genomic subtypes. In addition to differences in prevalence, variations in the type and pattern of TP53 mutations were observed between histologic types and between integrative genomic subtypes. TP53 hotspot mutations were significantly more frequently found in SECs (46%) than in EECs (15%). TP53-mutant EECs significantly more frequently harbored a co-occurring PTEN mutation than TP53-mutant SECs. Finally, a subset of TP53-mutant ECs (22%) was found to harbor frameshift or nonsense mutations. Given that nonsense and frameshift TP53 mutations result in distinct p53 immunohistochemical results that require careful interpretation, and that EECs and SECs display different patterns, types, and distributions of TP53 mutations, the use of the TP53/p53 status alone for the differential diagnosis of EECs and SECs may not be sufficient.

Molecular Pathology: Predictive, Prognostic, and Diagnostic Markers in Uterine Tumors

This article focuses on the diagnostic, prognostic, and predictive molecular biomarkers in uterine malignancies, in the context of morphologic diagnoses. The histologic classification of endometrial carcinomas is reviewed first, followed by the description and molecular classification of endometrial epithelial malignancies in the context of histologic classification. Taken together, the molecular and histologic classifications help clinicians to approach troublesome areas encountered in clinical practice and evaluate the utility of molecular alterations in the diagnosis and subclassification of endometrial carcinomas. Putative prognostic markers are reviewed. The use of molecular alterations and surrogate immunohistochemistry as prognostic and predictive markers is also discussed.

STAR and AKR1B10 are down-regulated in high-grade endometrial cancer

Endometrial cancer is the most frequent gynecological malignancy in the developed world. The majority of cases are estrogen dependent, and are associated with diminished protective effects of progesterone. Endometrial cancer is also related to enhanced inflammation and decreased differentiation. In our previous studies, we examined the expression of genes involved in estrogen and progesterone actions in inflammation and tumor differentiation, in tissue samples from endometrial cancer and adjacent control endometrium. The aims of the current study were to examine correlations between gene expression and several demographic characteristics, and to evaluate changes in gene expression with regard to histopathological and clinical characteristics of 51 patients. We studied correlations and differences in expression of 38 genes involved in five pathophysiological processes: (i) estrogen-stimulated proliferation; (ii) estrogen-dependent carcinogenesis; (iii) diminished biosynthesis of progesterone: (iv) enhanced formation of progesterone metabolites; and (v) increased inflammation and decreased differentiation. Spearman correlation coefficient analysis shows that expression of PAQR7 correlates with age, expression of SRD5A1, AKR1B1 and AKR1B10 correlate with body mass, while expression of SRD5A1 and AKR1B10 correlate with body mass index. When patients with endometrial cancer were stratified based on menopausal status, histological grade, myometrial invasion, lymphovascular invasion, and FIGO stage, Mann-Whitney U tests revealed significantly decreased expression of STAR (4.4-fold; adjusted p=0.009) and AKR1B10 (9-fold; adjusted p=0.003) in high grade versus low grade tumors. Lower levels of STAR might lead to decreased de-novo steroid hormone synthesis and tumor differentiation, and lower levels of AKR1B10 to diminished elimination of toxic electrophilic carbonyl compounds in high-grade endometrial cancer. These data thus reveal the potential of STAR and AKR1B10 as prognostic biomarkers, which calls for further validation at the protein level.

Recent Developments in Surgical Pathology of the Uterine Corpus

There have been several updates recently on the classification of uterine tumors. Endometrial carcinomas have traditionally been divided into 2 types, but some are difficult to classify and do not fit readily into either of the currently recognized categories. The Cancer Genome Atlas Research Network has recently defined 4 new categories of endometrial cancer on the basis of mutational spectra, copy number alteration, and microsatellite instability, which might provide independent prognostic information beyond established risk factors. The Society of Gynecologic Oncology, moreover, now recommends systematic screening of every patient with endometrial cancer for Lynch syndrome. The new definition of high-grade endometrial stromal sarcoma disregards the number of mitotic figures as a primary diagnostic criterion and instead specifies moderate atypia still resembling stromal origin but lacking the pleomorphism of undifferentiated uterine sarcoma; these tumors also harbor a JAZF1-SUZ12 gene rearrangement. Mitotic count, atypia, and coagulative necrosis are the main histologic criteria that define leiomyosarcoma. Determining the type of necrosis can be very challenging in patients receiving various treatment modalities for symptomatic fibroids before myomectomy, since key histologic features of ischemic-type necrosis are often absent. Ancillary stains including p16, p53, MIB-1, trichrome, and reticulin may be helpful in tumors harboring necrosis that is difficult to classify. Minimally invasive gynecologic surgeries have introduced histologic artifacts that complicate the diagnosis. It is essential to recognize these as procedure-related artifacts to avoid upstaging tumors and triggering unnecessary adjuvant treatment.

Clinical translation for endometrial cancer stem cells hypothesis

Endometrial cancer is the most frequent gynecological malignancy in developed world. Cancer stem cells (CSC) are recognized as a small proportion of cells among the tumor cell population that are capable of self-renewal, aberrant differentiation, and escape homeostasis. This review aims to systematize the existing evidence of CSC of endometrial cancer and its clinical translation. In endometrial cancer, the cancer stem cell hypothesis has been studied in vitro using the isolation of colony forming units, side population with dye efflux capacity, and tumorospheres. The stem cell markers for endometrial cancer do not have uniform characteristics, albeit CD133 and aldehyde dehydrogenase (ALDH) were being associated with CSC phenotype. The application of endometrial CSC on xenograft models proves the tumorigenic capacity of this small group of cells. The metastatic process has been explained due to epithelial-mesenchymal transition (EMT) in which CSC seems to have a critical role. The chemoresistance is characteristic of CSC that in endometrial cancer has been shown in CSC phenotype and associated with CSC markers. The most ambitious potential for CSC is the development of targeted therapies. Its application on endometrial cancer is still poor, being a future perspective for research.

Immunohistochemical and genetic profiles of endometrioid endometrial carcinoma arising from atrophic endometrium

OBJECTIVE

Endometrial carcinomas are divided into type I endometrioid endometrial carcinomas (EECs), thought to arise from hyperplastic endometrium, and type II nonendometrioid endometrial carcinomas, thought to arise from atrophic endometrium. However, a minority (20%) of EECs have atrophic background endometrium, which was shown to be a marker of a worse prognosis. This study compares the immunohistochemical and genetic profiles of this possible third type to that of the known two types.

METHODS

43 patients with grade 1 EEC and hyperplastic background endometrium (type I), 43 patients with grade 1 EEC and atrophic background endometrium (type III) and 21 patients with serous carcinoma (type II) were included (n=107). Tissue microarrays of tumor samples were immunohistochemically stained for PTEN, L1CAM, ER, PR, p53, MLH1, PMS2, β-catenin, E-cadherin and MIB1. The BRAF, KRAS, and PIK3CA genes were analyzed for mutations.

RESULTS

A significantly higher expression of ER and PR, and a lower expression of L1CAM, p53 and MLH1 were found in type I and III compared to type II carcinomas. Expression of E-cadherin was significantly reduced in type III compared to type I carcinomas. Mutation analysis showed significantly less mutations of KRAS in type III compared to type I and II carcinomas (p<0.01).

CONCLUSION

There appear to be slight immunohistochemical and genetic differences between EECs with hyperplastic and atrophic background endometrium. Carcinogenesis of EEC in atrophic endometrium seems to be characterized by loss of E-cadherin and a lack of KRAS mutations. As expected, endometrioid and serous carcinomas were immunohistochemically different.

Gynecologic Cancer InterGroup (GCIG) consensus review for clear cell carcinoma of the uterine corpus and cervix

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.