Morphologic and Immunohistochemical Study of Clear Cell Carcinoma of the Uterine Endometrium and Cervix in Comparison to Ovarian Clear Cell Carcinoma:

How Progesterone Receptor Expression Impacts Platinum Sensitivity in Ovarian Clear Cell Carcinoma: Insights from Clinical and Experimental Perspectives

Ovarian clear cell carcinoma (OCCC) is often considered a relatively platinum-resistant malignancy. The aim of this study was to explore the influence of progesterone receptor (PR) expression levels on platinum sensitivity and survival outcomes in people with OCCC. A retrospective analysis was conducted with 80 people with OCCC who underwent surgery followed by adjuvant chemotherapy. PR expression was assessed via immunohistochemical (IHC) staining and quantified using the H score. The platinum sensitivity and survival outcomes of patients with weak and strong PR expression were compared. Additionally, cisplatin viability and migration experiments were conducted with OCCC cell lines (ES-2 and TOV-21G) with varying PR isoform expressions. Among the 80 patients, 62 were classified as having platinum-sensitive disease, while 18 had platinum-resistant disease. The mean total PR H- score of platinum-sensitive tumors was significantly higher than that of platinum-resistant tumors (p = 0.002). Although no significant differences in progression-free and overall survival were observed between patients with high and low PR expression, those with high PR expression tended to have longer survival. While PR protein was only weakly detectable in ES-2 and TOV-21G cells, a transfection of the PR-A or PR-B gene resulted in a strong expression of PR-A or PR-B, which led to significantly reduced proliferation and migration in ES-2 and TOV-21G cells. Furthermore, overexpression of PR-A or PR-B enhanced cisplatin cytotoxicity in these cell lines. In conclusion, strong PR expression was associated with improved platinum sensitivity and survival outcomes, consistent with our experimental findings. The potential of PR as a tumor sensitizer to cisplatin in OCCC warrants further investigation.

State of the art of cervical cancer treatment in rare histologies

The objective of this review is to summarize the current scientific evidence to formulate clinical recommendations regarding the classification, diagnostic approach, and treatment of rare histological subtypes of cervical cancer; neuroendocrine carcinoma, gastric-type mucinous adenocarcinoma, and glassy cell adenocarcinoma. These histological subtypes are generally characterized by their low frequency, aggressive biological behavior, certain chemoradioresistance, and consequently, high recurrence rates with a deleterious impact on survival. Molecular studies have identified several associated mutations in neuroendocrine carcinoma (PIK3CA, MYC, TP53, PTEN, ARID1A, KRAS, BRCA2) and gastric-type adenocarcinoma (KRAS, ARID1A, PTEN) that may serve as molecular targets. While adenocarcinomas are typically treated and classified based on squamous histology across early, locally advanced, and advanced stages, the treatment strategies for neuroendocrine carcinomas in early stages or locally advanced cases differ, particularly in the sequencing of administering chemotherapy, chemoradiotherapy, or surgery. The chemotherapy regimen is based on etoposide plus cisplatin (EP). Unlike squamous cell carcinomas, immune checkpoint inhibitors are yet to establish a standard role in the treatment of recurrent neuroendocrine carcinomas due to the absence of clinical trials. Regarding glassy cell adenocarcinomas and gastric-type adenocarcinoma, the potential use of immunotherapy in advanced stages/disease requires further evaluation through international collaborations, given the limited number of cases.

The spectrum of oestrogen receptor expression in endometrial carcinomas of no specific molecular profile

AIMS

Decreased oestrogen receptor (ER) expression is a marker of poor prognosis in endometrial carcinomas (EC) of no specific molecular profile (NSMP), but the optimal cut-off to separate high-risk 'low ER' versus low-risk 'high ER' expression has not been defined. Here we characterised the distribution of ER staining in a cohort of ECs.

METHODS AND RESULTS

Biopsy specimens from 120 cases of NSMP EC were stained for ER and assigned an Allred score. In 66 additional cases ER staining of matched biopsy and hysterectomy were compared. Twelve of 120 tumours had an Allred score of 0-3, including three endometrioid carcinomas (EEA) (one G1, two G3), four clear cell carcinomas (CCC), two mesonephric-like adenocarcinoma (MLA) and one each of: gastric-type adenocarcinoma, carcinosarcoma and endometrial carcinoma NOS. Three had Allred scores of 4-5: two MLA and one high-grade carcinoma with yolk sac differentiation. Five had Allred scores of 6: four EEA (one G1, one G2, two G3) and one mixed clear cell and endometrioid carcinoma. The remaining 100 tumours with Allred scores ≥ 7 were all EEA (66 G1, 28 G2, five G3 and one grade unknown). Comparing the biopsy versus hysterectomy ER staining (n = 66), the results were within a single Allred score point, except two cases with strong diffuse expression in the biopsy (Allred 8) and moderate expression in the hysterectomy (Allred 5).

CONCLUSIONS

Most NSMP ECs (> 80%) show high ER expression (Allred score ≥ 7). All non-endometrioid carcinomas and a few endometrioid carcinomas had lower ER expression (Allred score ≤ 6) or were completely negative.

Cervical clear cell carcinoma: Case report and literature review

RATIONALE

Clear cell carcinoma (CCC) is a highly invasive malignant tumor. CCCs of the female reproductive system occur mostly in the endometrium and ovaries and rarely in the cervix. So, it is difficult to diagnose cervical clear cell carcinoma (CCAC) on imaging. This report helps to further deepen our understanding of CCAC.

PATIENT CONCERNS

A 39-year-old female patient presented with vaginal discharge with no obvious cause, elevated levels of carcinoembryonic antigen (CEA), CA125, CA153, and squamous cell carcinoma antigen (SCC), and underwent ultrasonography (US) CT and MRI examination in our hospital, which showed a mass in the cervix of the uterus, considered of cervical squamous carcinoma.

DIAGNOSES

The cervix biopsy guided by vaginoscope biopsy and immunohistochemistry confirmed CCAC, combined Magnetic Resonance Imaging examination, CCAC with pelvic lymph node metastasis was considered.

INTERVENTIONS AND OUTCOMES

The patient refused further treatment and was discharged from hospital.

LESSONS

CCAC exhibited no specific symptoms, and is slightly different from cervical squamous carcinoma in image features, mainly relying on immunohistochemistry for diagnosis. The reported case raised awareness of CCAC.

Pembrolizumab and lenvatinib in recurrent ovarian clear cell carcinoma resistant to chemotherapy

Background

Treatment of ovarian clear cell carcinoma (CCC) poses many challenges. Effective treatment options for recurrent and metastatic disease remain limited.

Case

A 70-year-old woman with recurrent metastatic ovarian CCC experienced durable response to the combination of pembrolizumab, a PD-1 targeting monoclonal antibody and lenvatinib, an oral multikinase inhibitor, after failing standard and experimental treatments. She experienced a 40.1% reduction of target lesions over 26 weeks of therapy. CA-125 trends confirmed serial CT scan findings of shrinking disease burden. She experienced overall mild side effects from the drug combination, and lenvatinib dosage was decreased from 20 to 10 mg/day over her 10 cycles.

Conclusion

The combination of pembrolizumab and lenvatinib may represent a new treatment option for chemotherapy-resistant ovarian CCC.

Next-generation sequencing shows the genomic features of ovarian clear cell cancer and compares the genetic architectures of high-grade serous ovarian cancer and clear cell carcinoma in ovarian and endometrial tissues

Ovarian clear cell carcinoma (OCCC) is a special histological type of epithelial ovarian cancer (EOC) that is not derived from epithelial cells of the ovarian or fallopian tube as the most common type of ovarian cancer, high-grade serous ovarian carcinoma (HGSOC), but is closely related to endometriosis and similar to endometrial clear cell carcinoma (ECCC) at morphologic and phenotypic features. However, limited data was shown in OCCC genomic features and compared with that in OCCC, HGSOC and ECCC. Herein, we utilized next-generation sequencing analysis of a panel of 1,021 genes to profile the mutational alterations in 34 OCCC and compared them to those from HGSOC (402 cases) and ECCC (30 cases). In result, the ARID1A and PIK3CA are high-frequency mutations of OCCC. Clonal architectures showed that all the mutations of genes occur in the later stage in the OCCC progress, whereas KRAS mutation is the earlier event compared with mutation of ARID1A or PIK3CA, which usually occurs in a group of ARID1A or PIK3CA mutations. The mutation frequency of main driver genes is similar between OCCC and ECCC, while TP53 is the main mutation in HGSOC and ECCC. Shared mutational signatures between OCCC and ECCC tissues with commonly observed a C>T change indicated a common carcinogens-exposed between these two carcinomas, but HGSOC and ECCC have common and distinct mutational signatures across cohorts respectively. In addition, we identified some novel CNV gains in NF1, ASXL1, TCF7L2, CREBBP and LRP1B and loss in ATM, FANCM, RB1 and FLT in OCCC. Our study offered a new perspective for OCCC tumorigenesis from two organs, the ovary and uterus, at genomic architectures and revealed novel CNV events for helping to provide theoretical support for OCCC treatment.

The Tumor Microenvironment of Clear-Cell Ovarian Cancer

Some patients with advanced clear-cell ovarian cancer (CCOC) respond to immunotherapy; however, little is known about the tumor microenvironment (TME) of this relatively rare disease. Here, we describe a comprehensive quantitative and topographical analysis of biopsies from 45 patients, 9 with Federation Internationale des Gynaecologistes et Obstetristes (FIGO) stage I/II (early CCOC) and 36 with FIGO stage III/IV (advanced CCOC). We investigated 14 immune cell phenotype markers, PD-1 and ligands, and collagen structure and texture. We interrogated a microarray data set from a second cohort of 29 patients and compared the TMEs of ARID1A-wildtype (ARID1Awt) versus ARID1A-mutant (ARID1Amut) disease. We found significant variations in immune cell frequency and phenotype, checkpoint expression, and collagen matrix between the malignant cell area (MCA), leading edge (LE), and stroma. The MCA had the largest population of CD138+ plasma cells, the LE had more CD20+ B cells and T cells, whereas the stroma had more mast cells and αSMA+ fibroblasts. PD-L2 was expressed predominantly on malignant cells and was the dominant PD-1 ligand. Compared with early CCOC, advanced-stage disease had significantly more fibroblasts and a more complex collagen matrix, with microarray analysis indicating "TGFβ remodeling of the extracellular matrix" as the most significantly enriched pathway. Data showed significant differences in immune cell populations, collagen matrix, and cytokine expression between ARID1Awt and ARID1Amut CCOC, which may reflect different paths of tumorigenesis and the relationship to endometriosis. Increased infiltration of CD8+ T cells within the MCA and CD4+ T cells at the LE and stroma significantly associated with decreased overall survival.

HER2 Expression in Endometrial Cancers Diagnosed as Clear Cell Carcinoma

There is increasing evidence that many endometrial cancers (EC) diagnosed as clear cell carcinoma (CCC) have substantial overlap with both serous carcinoma (SC) and endometrioid carcinoma (EmC), not only in terms of morphology and immunophenotype but also by molecular characterization. Now with use of HER2-based therapy in SC, a CCC diagnosis in serous-like tumors has the potential to exclude patients from receiving beneficial therapy. To assess HER2 in CCC in relation to other characteristics, a tissue microarray of archived CCC, EmC, and SC was stained for HER2 alongside a battery of immunostains used in EC. Cases with equivocal HER2 IHC were also assessed by in situ hybridization. HER2 status was assessed in 229 cases (23 CCC, 74 SC, 132 EmC). HER2 was positive in 48% of cases diagnosed as CCC, 19% of SC, and 0% of EmC. Rigorous morphologic and immunophenotypic review by 5 gynecologic pathologists revealed diagnostic disagreement in 8/11 HER2+ cases diagnosed as CCC, with SC as the other major diagnostic consideration. All HER2+ (n=25) cases were MMR-intact and most HER2+ EC had aberrant p53 staining (22/25, 88%); the 3 cases with a wild type pattern for p53 (12%) were all negative for ER. Based on these findings, patients with a diagnosis of CCC should be included in future clinical trials of HER2-targeted therapy. Moreover, given the diagnostic difficulty surrounding CCC, immunohistochemistry-based algorithms that include aberrant p53 and/or the absence of ER expression may provide a more objective means of establishing eligibility criteria than is currently possible using traditional histologic classification.

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).

Cervical cytology in the detection of uterine clear cell carcinoma: Diagnostic predictors from a case-control study

INTRODUCTION

Uterine clear cell adenocarcinoma (CCC) is a rare, aggressive malignancy with poor prognosis. The present study aimed to identify and describe its characteristic morphological features in cervical cytology.

METHODS

This was a 3-year retrospective case-control study. Cases included cervical samples of histopathologically proven endometrial and cervical CCC. Controls included cervical samples of histopathologically proven endometrial serous carcinoma (n = 15), endometrioid adenocarcinoma (n = 20), and endocervical adenocarcinoma (n = 15). Twenty-eight cytomorphological features were evaluated; the strength of association was determined by odds ratio (OR) and Cramer's V, and the diagnostic accuracy of statistically significant features was assessed.

RESULTS

Cases consisted of histopathologically proven 25 (34.7%) endometrial and 13 (18.0%) cervical CCC. Corresponding cervical samples were available for a total of 14 (36.8%) patients, of which 13 (92.8%) were positive for epithelial cell abnormality. On univariate analysis, three cytomorphological variables were significant predictors of uterine CCC: presence of dense cytoplasm (OR = 88; V = 0.72), deep nuclear membrane irregularities (OR = 17.5; V = 0.55), and coarse chromatin (OR = 21.3; V = 0.46). Dense cytoplasm had the highest positive predictive value (92%) and high specificity (97.8%), whereas coarse chromatin had the highest sensitivity (92.3%) and negative predictive value (96.7%).

CONCLUSIONS

The presence of dense cytoplasm and deep nuclear membrane irregularities in the tumour cells were strong predictors, and coarse chromatin a moderate predictor, of uterine CCC compared to its close cytological mimics.

Napsin-A and AMACR are Superior to HNF-1β in Distinguishing Between Mesonephric Carcinomas and Clear Cell Carcinomas of the Gynecologic Tract

Mesonephric carcinoma is a rare gynecologic neoplasm commonly mistaken for clear cell carcinoma, because of their overlapping morphologic features. Both tumors are negative for estrogen receptor and p16, magnifying this diagnostic dilemma. Recently, hepatocyte nuclear factor-1 beta (HNF-1β), a marker for clear cell carcinoma, has also been shown to be positive in mesonephric carcinomas. Other more recent markers for clear cell carcinoma, however, such as Napsin-A and alpha-methylacyl-CoA racemase (AMACR), have not yet been studied in mesonephric carcinomas. Here we examine HNF-1β, AMACR, and Napsin-A immunohistochemistry in 18 mesonephric and 55 endometrial/cervical clear cell carcinomas. HNF-1β was considered positive if nuclear staining was present in ≥70% of cells and at least moderate intensity; for Napsin-A and AMACR, any cytoplasmic staining was considered positive (≥1%). H-scores were determined by multiplying the intensity score by proportion score. HNF-1β was positive in a substantial portion of mesonephric carcinomas (9/18, 50%; H-score 98) and clear cell carcinomas (34/55, 62%; H-score 163) and did not distinguish between the 2 entities (specificity, 50%; P-value of H-score=0.08). Napsin-A and AMACR expression was significantly higher in clear cell [43/55 (78%) and 41/55 (75%), respectively] than mesonephric carcinomas [4/18 (22%) and 4/18 (22%) respectively], and helpful in this differential (specificity: 78% and 78%; P<0.05 for both). When Napsin-A and AMACR staining were seen in mesonephric carcinomas, staining was focal (≤5%), whereas staining in clear cell carcinomas was patchy/diffuse. In summary, Napsin-A and AMACR are helpful in distinguishing mesonephric carcinomas from clear cell carcinomas of the female genital tract, but HNF-1β is not.

Clear cell endometrial carcinomas with mismatch repair deficiency have a favorable prognosis: A systematic review and meta-analysis

INTRODUCTION

In the ESGO/ESTRO/ESP guidelines for endometrial carcinoma management, the risk category of clear cell carcinoma (CCC) is not well defined. In fact, while p53-abnormal (p53abn) CCC are known to be aggressive, the prognosis of mismatch repair-deficient (MMRd) and p53-wild-type (p53wt) CCCs is less clear.

OBJECTIVE

To assess the prognostic value of the MMRd and p53wt groups in CCC through a systematic review and meta-analysis.

METHODS

Electronic databases were searched from their inception to February 2021. All studies reporting p53 expression, MMR proteins expression and survival outcomes in endometrial CCC (either pure or mixed) were included. Kaplan-Meier and Cox regression survival analyses with hazard ratio (HR) for overall survival (OS) were performed by using the p53abn group as reference; a significant p-value<0.05 was adopted.

RESULTS

Six studies with 136 CCC (114 pure and 22 mixed) were included. Five-year OS was 95.7 ± 4.3% in the MMRd group, 48.4 ± 8.4% months in the p53wt group and 40.6 ± 10.4% in the p53abn group. The hazard of death was significantly lower in the MMRd group than in the p53abn group (HR = 0.062; p = 0.007), while it did not significantly differ between the p53wt and the p53abn group (HR = 0.673; p = 0.222). The POLEmut group could not be analyzed due to the absence of deaths. Similar results were observed in the pure CCC and mixed CCC subgroups.

CONCLUSION

MMRd CCCs seem to have a favorable prognosis and might be lumped together with MMRd endometrioid carcinoma for management purpose. On the other hand, p53wt CCCs appear prognostically more similar to p53abn CCCs.

A study on the immunohistochemical expression of napsin A in oral squamous cell carcinomas, intraepithelial neoplasia, and normal oral mucosa

Napsin A is an aspartic proteinase expressed in some types of carcinomas, such as lung adenocarcinomas and renal cell carcinomas but rarely in squamous cell carcinomas. No specific studies have been carried out focusing on napsin A antibody expression in oral squamous cell carcinomas (OSCC). The aim of this study was to investigate the reactivity of this antibody in primary OSCC. This retrospective study included 70 OSCC cases of which 31 (44.3%) presented metastasis involvement. Patient data, including age, gender, tumor location, histological grade, regional and distant metastasis, were collected. OSCC edge epithelium with intraepithelial neoplasia and healthy oral mucosa (n = 10) were included in the analysis. Sections of lung adenocarcinomas (n = 2) were used as the positive control and an immunohistochemical assay for napsin A was performed on all cases. Napsin A expression was negative in all 70 cases of OSCC, as well as in the intraepithelial neoplasia adjacent to the carcinoma area and in healthy oral mucosa epithelium. Metastatic neck lymph nodes and distant organs were also negative for napsin A. This study shows that napsin A is consistently not expressed in oral squamous cell carcinoma, or in metastatic sites of primary OSCC, intraepithelial neoplasia, and healthy oral mucosa.

Adenocarcinoma of the Uterine Cervix: Immunohistochemical Biomarker Expression and Diagnostic Performance

Immunohistochemistry (IHC) improves the diagnosis of cervical adenocarcinoma but is not adequately studied. The performance of 16 antibodies previously reported as potentially discriminating between some histotypes was investigated in 184 tumors comprised of 12 histotype groups collapsed into 3 categories [47 adenocarcinomas in situ (AIS), 121 probable human papillomavirus-dependent adenocarcinomas (HPVD), and 16 of probable independence (HPVI)]. IHC sections from 5 tissue microarrays were scanned, and 3 pathologists independently reviewed images to assess staining percentages and intensities. Biomarker expression was based on published positive and negative cutoffs and agreement between any 2 pathologists. Differences between the 3 categories in the hierarchical ranking of biomarker positivity were analyzed by Random Forest classification, and between select groups by Unsupervised Hierarchical Clustering. Important category discriminants were combined in logistic regression models and the area under the curve (AUC) computed. Potential group discriminants were terminal cluster biomarkers with a 50% or more difference in positivity. Strong associations occurred between the lower expression of carcinoembryonic antigen and stromal actin in AIS compared with HPVD [AUC=0.70, 95% confidence interval (CI), 0.59-0.80] and in the higher expression of p16 and estrogen receptor in comparison to HPVI (AUC=0.86, 95% CI, 0.73-0.98), and between the higher expression of p16, carcinoembryonic antigen and estrogen receptor in HPVD compared with HPVI (AUC=0.88, 95% CI, 0.77-0.99). Between select groups, 9 biomarkers emerged as potential discriminants. Select IHC biomarkers can discriminate AIS from invasive adenocarcinomas, and invasive adenocarcinomas stratified by human papillomavirus dependency from each other. Independent replication in larger studies is needed, and to confirm discriminants of histotype groups.

A Comprehensive Review of Biomarker Use in the Gynecologic Tract Including Differential Diagnoses and Diagnostic Pitfalls

Morphologic (ie, hematoxylin and eosin) evaluation of the Mullerian tract remains the gold standard for diagnostic evaluation; nevertheless, ancillary/biomarker studies are increasingly utilized in daily practice to assist in the subclassification of gynecologic lesions and tumors. The most frequently utilized "biomarker" technique is immunohistochemistry; however, in situ hybridization (chromogenic and fluorescence), chromosomal evaluation, and molecular analysis can also be utilized to aid in diagnosis. This review focuses on the use of immunohistochemistry in the Mullerian tract, and discusses common antibody panels, sensitivity and specificity of specific antibodies, and points out potential diagnostic pitfalls when using such antibodies.

Napsin A Expression in Subtypes of Thyroid Tumors: Comparison with Lung Adenocarcinomas

Napsin A is widely used in the diagnosis of lung adenocarcinoma and has also been reported to be positive in cases of thyroid carcinomas. We investigated napsin A levels through immunohistochemistry on whole sections of 210 primary thyroid tumors of various subtypes and another 41 metastatic thyroid carcinomas, and compared these with 125 primary and 25 metastatic lung adenocarcinomas. The results showed that napsin A was expressed in 23.8% thyroid tumors and 30.3% papillary thyroid carcinomas. Most cases showed a focal and weak to moderate expression. In comparison, 80.8% primary lung adenocarcinomas expressed napsin A, with mostly diffused and strong expression. For metastatic carcinomas of thyroid and lung origin, napsin A was detected in 39.0% of thyroid carcinomas in contrast to 88.0% in cases of lung adenocarcinomas. Comparisons of additional markers, TTF-1, CK7, thyroglobulin, and Pax-8 in metastatic carcinomas showed the overlapping expression of immunomarkers of TTF-1 and CK7. Thyroglobulin and Pax-8 were useful for distinguishing between metastatic carcinomas; however, Pax-8 may be a superior marker due to its higher sensitivity. The clinicopathological analysis of papillary thyroid carcinomas showed that the expression of napsin A was positively correlated with lymph node metastasis (p = 0.030). Here, we focused on the expression of napsin A in thyroid tumors and compared it with that in lung adenocarcinomas. The expression of napsin A is common in thyroid tumors and the combined expression of napsin A and TTF-1 in a metastatic thyroid carcinoma is a cause for concern due to chances of misdiagnosis as lung adenocarcinoma.

Diagnostic Algorithmic Proposal Based on Comprehensive Immunohistochemical Evaluation of 297 Invasive Endocervical Adenocarcinomas

The International Endocervical Adenocarcinoma Criteria and Classification was developed to separate endocervical adenocarcinomas (ECAs) into 2 main categories on the basis of morphology such as human papilloma virus-associated (HPVA) and non-human papilloma virus-associated adenocarcinomas. We aimed to improve the diagnostic accuracy of International Endocervical Adenocarcinoma Criteria and Classification by performing a comprehensive immunohistochemical evaluation and constructing objective immunohistochemical-based algorithms for the classification of these tumors. Tissue microarrays were constructed from 297 of 409 cases used to develop the original classification. Immunostains included p16, p53, estrogen receptor (ER), progesterone receptor, androgen receptor, Vimentin, CK7, CK20, HER2, HIK1083, MUC6, CA-IX, SATB2, HNF-1beta, napsin A, PAX8, CDX2, GATA3, p63, p40, and TTF-1. High-risk human papilloma virus (HR-HPV) was detected by in situ hybridization (ISH) using probes against E6 and E7 mRNA expressed in 18 different virus types. Vimentin, ER, and progesterone receptor were expressed in a significant minority of ECAs, mostly HPVAs, limiting their use in differential diagnosis of endometrioid carcinoma when unaccompanied by HPV-ISH or p16. HR-HPV ISH had superior sensitivity, specificity, and negative and positive predictive values compared with p16, as published previously. HNF-1beta did not have the anticipated discriminatory power for clear cell carcinoma, nor did MUC6 or CA-IX for gastric-type carcinoma. HNF-1beta and napsin A were variably expressed in clear cell carcinoma, with HNF-1beta demonstrating less specificity, as it was ubiquitously expressed in gastric-type carcinoma and in the majority of HPV-associated mucinous (predominantly intestinal-type and invasive ECA resembling stratified mucin-producing intraepithelial lesion [iSMILE]) and usual-type carcinomas. HIK1083 was expressed in nearly half of gastric-type carcinomas, but not in the vast majority of other subtypes. GATA3 was positive in 10% of usual-type adenocarcinomas and in single examples of other subtypes. Rare gastric-type and HPVA mucinous carcinomas displayed HER2 overexpression. Androgen receptor was positive in 6% of usual-type adenocarcinomas. Aberrant p53 expression was found in only 3.6% of usual-type HPVA carcinomas, but it was more prevalent in mucinous (intestinal type and iSMILE) HPVAs and non-human papilloma virus-associates (particularly in gastric-type carcinoma, >50% of cases). The following diagnostic classification algorithms were developed with the above data. Carcinomas without overt cytoplasmic mucin (endometrioid, usual-type endocervical, clear cell, and mesonephric carcinomas) can be subclassified using HR-HPV ISH, ER, and GATA3, whereas carcinomas with easily appreciated cytoplasmic mucin (endometrioid carcinoma with mucinous features, HPVA mucinous, and gastric-type carcinomas) can be subclassified with HR-HPV ISH and ER.

Clear cell carcinomas of the ovary and kidney: clarity through genomics

Clear cell ovarian carcinoma (CCOC) and clear cell renal cell carcinoma (ccRCC) both feature clear cytoplasm, owing to the accumulation of cytoplasmic glycogen. Genomic studies have demonstrated several mutational similarities between these two diseases, including frequent alterations in the chromatin remodelling SWI-SNF and cellular proliferation phosphoinositide 3-kinase-mammalian target of rapamycin pathways, as well as a shared hypoxia-like mRNA expression signature. Although many targeted treatment options have been approved for advanced-stage ccRCC, CCOC patients are still treated with conventional platinum and taxane chemotherapy, to which they are resistant. To determine the extent of similarity between these malignancies, we performed unsupervised clustering of mRNA expression data from these cancers. This review highlights the similarities and differences between these two clear cell carcinomas to facilitate knowledge translation within future research efforts. Copyright © 2018 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

Cervical clear cell adenocarcinoma with an exceptionally low proliferation index: Report of a case

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A histologically low-grade cervical clear cell lesion was observed.

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Proliferating cells were seen only at the periphery of this lesion.

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Due to its low proliferation index, this may represent a precursor of clear cell carcinoma.

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Further definition of such lesions may allow for more minimal management.