Clear cell carcinoma of breast lipid-rich variant

Clear cell breast carcinomas are one of the rare types of invasive carcinoma of the breast. Among them, lipid-rich variant is still rare comprising <1%. The tumor derives its name from the intracytoplasmic neutral lipid that gives the cytoplasm a vacuolated and foamy appearance. These tumors are usually hormone receptors negative and Her-2 Neu positive. Here, we report a case of lipid-rich breast carcinoma which showed hormone receptor positivity and Her-2 Neu negative.

Development and Differentiation of Epididymal Epithelial Cells in Korean Native Black Goat

Simple Summary

Studies have revealed that the communication networks among epididymal epithelial cells play an essential role in sperm maturation and storage. Therefore, the localization and expression of V-ATPase and cytokeratin 5 in the clear cells and basal cells, respectively, of immature and mature goat epididymis was investigated. To the best of our knowledge, the present study is the first to use immunofluorescence labeling and confocal imaging to characterize the differentiation of clear cells and basal cells in the goat epididymis. The findings could help the understanding of the regulatory mechanism that creates an optimal luminal environment for sperm maturation and storage in the epididymis.

Abstract

The acidic luminal environment of the epididymis is regulated by the communication networks among epididymal epithelial cells; it is necessary for sperm maturation and storage. To characterize epididymal epithelial cell differentiation, the localization and expression of hydrogen-pumping vacuolar ATPase (V-ATPase) and cytokeratin 5 (KRT5) in the clear and basal cells, respectively, of immature and mature goat epididymis and vas deferens was examined. The epididymides and vas deferens were obtained from goats aged 1, 2, and 12–14 months. To assess the localization and expression patterns of V-ATPase and KRT5 in the caput, corpus, and cauda of the epididymis and proximal vas deferens, the tissue sections were subjected to immunofluorescence labeling and observed by confocal microscopy. Both clear and basal cells progressively started to differentiate in a retrograde manner. Clear cells disappeared from the cauda region after puberty, and they were maintained only in the caput and corpus regions of the adult goat epididymis. V-ATPase and KRT5 were co-expressed in the differentiated cells located at the base of the epithelium (i.e., basal cells). This cell type-specific differentiation and distribution of the epithelial cells plays a critical role in establishing a unique luminal environment for sperm maturation and storage in the goat epididymis.

The current clinical approach to newly diagnosed uterine cancer

INTRODUCTION

Uterine cancer is the most common gynecologic malignancy, although fortunately, 75% of women present with early-stage disease. A major area of controversy regarding the management of the disease concerns postoperative therapy for both women with early- and advanced-stage endometrial carcinoma. Here, we review landmark evidence that can help guide clinical decision-making in the treatment of women diagnosed with endometrial cancer.

AREAS COVERED

In this review, we present the latest data driving decisions for both surgical management and postoperative therapy for women with endometrial carcinoma. Areas discussed include surgical staging, with a specific discussion on the role of sentinel lymph node mapping, and postoperative therapy, ranging from the data supporting observation for women with early-stage, low-risk disease to combination therapy for women with advanced disease. Less common histologies, such as serous and clear cell carcinoma, as well as carcinosarcoma, will also be covered. Furthermore, a section of the paper is dedicated to the current state of fertility-sparing surgery.

EXPERT OPINION

We suggest several approaches for deciding on adjuvant therapy, based on stage and histology, after comprehensive surgical staging. The role that endometrial cancer molecular subtypes will play on postoperative therapy remains to be fully investigated.

Atypical Presentation of Gastrointestinal Stromal Tumor as Multiple Intra-Abdominal Cysts: A Case Report

Gastrointestinal stromal tumors (GISTs) are the most common nonepithelial solid neoplasms involving the alimentary tract. We report a case of cystic GIST with multiple cystic metastases. A 61-year-old man presented with upper abdominal pain for two months. Further evaluation revealed a large intra-abdominal cyst in the lesser sac and another cyst over the segment VII of the liver on imaging. Multiple intra-abdominal hydatidoses were suspected based on the imaging and its endemic nature in the geographical area. However, the hydatid serology was normal. In view of hemorrhagic cyst fluid, an intraoperative frozen biopsy of the cyst wall was done, which revealed features suspicious of a mesenchymal tumor. Sleeve gastrectomy with en-bloc excision of the gastric cyst, excision of the hepatic cyst, and complete excision of multiple other intra-abdominal cysts were performed considering GIST as a possibility. Histology revealed a clear cell variant of GIST. Gastric GISTs primarily presenting as multiple intra-abdominal cysts and of clear cell histological variants had never been reported in the literature. The patient was started on imatinib, and he has shown no evidence of recurrence after 12 months of follow-up.

A high index of suspicion, intraoperative frozen section, meticulous surgery, and immunohistochemistry are all crucial for the effective management of atypical cases. GIST may be considered as a part of differential diagnosis in clinical scenarios with multiple intra-abdominal cysts, especially in the equivocal setting.

Prognosis of ovarian clear cell cancer compared with other epithelial cancer types: A population-based analysis

In order to compare the clinicopathological characteristics and survival outcomes of patients with ovarian clear cell carcinoma (CCC) to other epithelial cancer types, a total of 27,290 patients were analyzed, including 2,424 patients with CCC (8.9%), 3,505 patients with endometrioid cancer (EC) (12.8%), 2,379 patients with mucinous cancer (MC) (8.7%) and 18,982 patients with serous cancer (SC) (69.6%). Patients with EC had the most favorable prognosis and patients with SC had the poorest prognosis among all epithelial ovarian cancers. Among patients with stage I cancer, patients with CCC had a more favorable prognosis compared with patients with SC, especially after 60 months (landmark analysis results, HR=2.079, P=0.001) and had a poorer prognosis compared with patients with MC [restricted mean survival time (RMST) difference, −3.434 months]. Among patients at stages III and IV, patients with CCC had a poorer prognosis compared with patients with SC (RMST difference in stage III, −7.588 months; RMST difference in stage IV, −15.445 months) and had a more favorable prognosis compared with patients with MC (RMST difference in stage III, 10.850 months; RMST difference in stage IV, 8.430 months). The present results suggested that most patients with CCC exhibited, high grade, an early stage, unilateral status and were of a young age. In general, patients with SC presented the poorest prognosis among all patients with epithelial ovarian cancer and no significant survival difference was found between patients with CCC and MC. However, after adjusting for stage using pairwise comparisons, the prognosis of patients with CCC was found to be more favorable compared with the patients with SC and worse compared with patients with MC at stage I; the results at stage III–IV were opposite and the prognosis of patients with CCC was worse compared with the patients with SC and more favorable compared with the patients with MC.

Identification of Myoferlin Expression for Prediction of Subsequent Primary Malignancy in Patients With Clear Cell Renal Cell Carcinoma

BACKGROUND/AIM

Multiple primary malignant tumors are common in patients with renal cell carcinoma. However, reports on the factors that can identify patients with a risk for subsequent primary malignancies have been lacking. This study aimed to investigate whether myoferlin expression can be used as a potential marker to predict subsequent primary malignancies in patients with clear cell renal cell carcinoma (ccRCC).

MATERIALS AND METHODS

We evaluated the relationship of subsequent primary malignancies with clinicopathological factors and myoferlin expression in 152 patients with ccRCC, and we analyzed the strength of the association with myoferlin expression.

RESULTS

The development of subsequent primary malignancies exhibited significant correlation with patient age (p=0.029), sex (p=0.015), T stage (p<0.001), and myoferlin expression (p=0.017). Furthermore, myoferlin hyperexpression was determined as an independent risk factor for developing a subsequent primary malignant tumor in patients with ccRCC (odds ratio(OR), 2.485, 95% Confidence Interval(CI)=1.052-5.870, p=0.038).

CONCLUSION

Myoferlin hyperexpression can be a useful marker for predicting the development of subsequent primary malignancies in patients with ccRCC.

Clear cell variant of Oral Squamous cell carcinoma

Among the various histopathological variants of oral squamous cell carcinoma, clear cell variant is a rarity. (1) This report is a compilation of two cases which showed the presence of clear cells. The clear cells were of koilocytic type. Although clear cell variant of squamous cell carcinoma is more common in skin, few cases have been found in oral region also. (2) This variant is considered more aggressive than the others, and hence requires more aggressive treatment protocol. Being rare, the percentage of clear cells determines whether it should be considered as a clear cell variant. The literature has been evaluated for similar cases, and discussed about the clear cells and their origin. An effort has also been made to compile the reported cases of clear cell variant of OSCC.

Invasive Lobular Carcinoma With Extensive Clear Cells: A Pitfall in Diagnosis

Carcinomas in the breast with a predominantly clear cytoplasm are rare. In this article, we review the differential diagnosis of clear cell breast neoplasms and report a case of invasive lobular carcinoma with extensive clear cell morphology that was diagnosed as invasive ductal carcinoma, not otherwise specified, on ultrasound-guided biopsy. Lobular carcinomas with extensive clear cell change are unusual, but must be considered when evaluating a clear cell neoplasm in the breast.

IDUA, NDST1, SAP30L, CRYBA4, and SI as novel prognostic signatures clear cell renal cell carcinoma

Carcinoma of the kidney is one of the most prevalent carcinoma worldwide. The majority types of carcinoma are clear cell renal cell carcinoma (CCRCC), which consist more than 80% of the cases. As a genetically diverse disease, identification of prognosis-related genes has utmost importance in the early diagnosis and prognosis of the CCRCC. In this study, we performed gene expression profiling to identify prognosis-related genes for CCRCC. In addition, we developed and validated a gene signature-based risk score to comprehensively assess the prognostic function of differentially expressed genes. Furthermore, we performed a ROC analysis to identify the optimal cut-off point for classification risk level of the patients. Univariate Cox regression models were used to assess the association between differentially expressed genes in relation to the prognosis of patients with different stages of CCRCC. Five genes were identified significantly differentially expressed in CCRCC and associated with their survival time, namely: IDUA, NDST1, SAP30L, CRYBA4, and SI. A 5-gene signature-based risk score was developed based on the Cox coefficient of the individual genes. The prognostic value of this risk score was validated in an internal testing data set. In summary, a gene-based risk score was identified and validated, which can predict CCRCC patient survival. The potential functions of this gene expression signature and individual differentially expressed gene as prognostic targets of CCRCC were revealed by this study. Furthermore, these findings may have important implications in the understanding of the potential therapeutic method for the CCRCC patients.

Two Cases of Rare Pancreatic Malignancies

Background: Pancreatic adenocarcinoma remains one of the most lethal malignancies with little treatment advancements. Other less common pancreatic cancer histologies have different outcomes and disease course. In this article, we report two cases of rare pancreatic tumors.

Presentation: The first case is a 59-year old, who was undergoing surveillance of a known pancreatic cyst, which eventually enlarged. The mass was resected and pathology revealed undifferentiated carcinoma with osteoclast-like giant cells. The patient did not receive any adjuvant therapy and has had no recurrence. The second case is of a 60-year-old patient who presented with signs and symptoms of pancreatic insufficiency and was found to have clear cell adenocarcinoma of the pancreas. She received neoadjuvant chemoradiotherapy followed by surgical resection without complications.

Conclusion: Our article presents these rare malignancies, which had outcomes that are more encouraging than typical adenocarcinomas. Genomic sequencing can provide more insight into these tumors and potentially provide targets for therapy.

Psammomatoid Calcification-Rich Oncocytic Thyroid Adenoma With Clear-Cell Change

Abundant calcifications and clear-cell change may occur in oncocytic thyroid adenoma (OTA). We aimed to report the features of a case of OTA peculiar by the presence of extensive calcifications and of a clear-cell component. The OTA was detected on a right thyroid lobectomy specimen. Clear-cell change was observed in 15%-20% of the cells. Numerous, focally confluent psammomatoid calcifications, resulting in macrocalcifications, were identified. The nodule cells, uni- or multinucleated oncocytes, including those with clear cytoplasm, expressed heterogeneously TTF1, S100 protein, Bcl2, CD10, as well as CD138 and CD56. Lipid-droplet markers adipophilin and TIP47 were also expressed. In conclusion, we report a rare type of OTA, peculiar by the presence of numerous psammomatoid calcifications and of macrocalcification and by the presence of clear-cell change. Heterogeneity in membrane CD56 and/or CD138 expression as well as cytoplasmic heterogeneity of Bcl2 and lipid-droplet marker TIP47 might be relevant for calcification and clear-cell change, requiring further investigation.

Clear Cell Variant of Solid Pseudopapillary Neoplasm of the Pancreas: A Report of a Rare Variant and Review of the Literature

The clear cell variant of solid pseudopapillary neoplasm (ccSPN) of the pancreas was first described in 2006. In this article, we report a case of this rare variant and review the few published reports. Both the current and previous reports show that ccSPN has several morphologic differences from conventional SPN, including clear vacuoles, fewer pseudopapillary formations, more solid/diffuse architecture, less hemorrhage, and fewer cholesterol clefts. Some of these features peculiar to ccSPN, such as solid/diffuse architecture, have been proposed to suggest aggressive behavior, though reports of ccSPN are rare and often have limited clinical follow-up. ccSPN also appears to occur more frequently in males than conventional SPNs. These clinical and pathologic features lead to unique set of differential diagnostic considerations for ccSPN, including metastatic renal cell carcinoma, perivascular epithelial cell tumor, and clear cell variants of other carcinomas. These unique features, atypical differential, and uncertain prognostic ramifications all make ccSPN an important variant to be aware of and report.

RAB27A is an independent prognostic factor in clear cell renal cell carcinoma

AIM

To examine the expression of RAB27A and RAB27B in clear cell renal cell carcinoma (CCRCC).

MATERIALS & METHODS

The intensity and proportion of tumor cells staining positive for RAB27A and RAB27B in a total of 304 cores were evaluated.

RESULTS

The T stage showed a significant correlation with RAB27A intensity (p < 0.001). In multivariate analysis, CCRCC with negative intensity of RAB27A expression demonstrated poor disease-specific survival (hazard ratio: 6.821, 95% CI: 1.128-41.241; p-value = 0.036).

CONCLUSION

RAB27A is an independent prognostic factor in CCRCC.

Ameloblastic carcinoma ex ameloblastoma of the maxilla

Ameloblastic carcinoma (AC) is a rare malignant odontogenic tumor. Approximately 138 cases were reported. The majority of these cases occurred in the mandible. Only 57 cases were located in the maxilla. Most of AC cases occur in a primary type. Little is known about AC secondary type (dedifferentiated) since only six cases have been reported. All of previous six cases occurred in the mandible. Here, we presented the first case of maxillary AC secondary type (dedifferentiated) in a 46-year-old female. The first excisional biopsy was diagnosed as basal cell ameloblastoma. Then, the patient underwent partial maxillectomy. A recurrence occurred 17 months later. At this time, tumor cells with cytological atypia were clearly detected. A diagnosis of AC was rendered. Two years later, the patient suffered from another recurrence and received a wide excision with a diagnosis of AC. We considered our case as AC secondary type (dedifferentiated). We discussed the histopathological findings that may be helpful in making a diagnosis of AC. In addition, we consider that the basaloid pattern may be related to malignant transformation in ameloblastoma.

Clear cell "sugar" tumor of the lung: a case report and review of the literature

Clear cell "sugar" tumor of the lung is a rare benign tumor that is often an incidental finding during histopathologic workup. It strikingly has a similar resemblance to renal cell carcinoma (RCC) cells. Under the microscope, it is composed of thin cell walls and high levels of glycogen. Therefore, when diagnosed, it is important to rule out metastatic RCC. Here, in this case report, we present a case of clear cell "sugar" tumor of the lung and review the literature that has been published. Clear cell tumor of the lung needs to be studied more extensively as it can present with unique signs and symptoms. It has also occurred in the presence of systemic diseases. This has led researchers to theorize about its etiology which we discuss in this case report.

Peripheral clear cell variant of calcifying epithelial odontogenic tumor devoid of calcification

A clear cell variant of calcifying epithelial odontogenic tumor (CCEOT) affecting an extraosseous site is described. A 60-year-old male patient presented with gingival swelling on the lingual side of the anterior mandible. The results of biopsy suggested clear cell odontogenic carcinoma, and marginal resection of the mandible was performed. The resected specimen was composed of eosinophilic and clear cells with deposits of amyloid-like material. The clear cells exhibited granules that were positive for PAS. There was no calcification in the resected lesion. Based on these features, the conclusive diagnosis was peripheral CCEOT without calcification. No signs of recurrence were evident after 3 years of follow-up.

Relationship Among Tumor Attenuation Value of Pre-contrast Computed Tomography (CT), Washout Rate and Constituent Cells in Adrenal Adenoma: Proposition of a New Approach for Diagnosing Adrenal Adenoma on Dynamic CT

AIM

To elucidate the relationship among tumor attenuation of pre-contrast-enhanced (TApre) computed tomography (CT), washout rate and clear cell ratio (CCR) in adrenal adenoma (AA) and propose a new approach for diagnosing AA on dynamic CT.

MATERIALS AND METHODS

The training set consisted of 43 AAs and 15 non-AAs, while the validation set comprised 44 AAs and 11 non-AAs. Using the training set, the pairwise correlation between CCR, TApre and washout rate in AA was evaluated by linear regression analysis. A predictive formula for diagnosing AA was established by multiple logistic regression analysis using washout rate and TApre. Using the validation set, the diagnostic performance of this formula was investigated by comparing with the conventional diagnostic criteria: TApre ≤10 HU or washout rate ≥an optimal threshold calculated in the training set.

RESULTS

Washout rate increased as CCR decreased, and as TApre increased. The formula predicting the probability of AA was: p(AA)=1/{1+exp(-1.5257+0.4923× TApre-0.3264×washout rate)}. Diagnostic performance of this formula was sensitivity of 93.2% and accuracy of 89.1%, while for the conventional diagnostic criteria, sensitivity was 81.8-86.4% and accuracy 81.8-83.6%.

CONCLUSION

The diagnostic potential of dynamic CT for diagnosing AA may be improved by changing the threshold of washout rate based on substituting TApre for CCR.

Clear cell carcinoma of the ovary: Clinicopathologic features and outcomes in a Chinese cohort

This retrospective analysis aimed to clarify the clinical and pathologic features of ovarian clear cell carcinoma (OCCC), and to determine the factors predictive of survival.Data waereextracted from OCCC patients who underwent primary surgery followed by adjuvant chemotherapy in Obstetrics & Gynecology Hospital of Fudan University between January2007 and December 2014. Kaplan-Meier survival estimates and Cox proportional hazards model were used for survival analyses.Of 130 patients (mean age = 56.2 years), 66.2% had stage I disease when the 5-year overall survival and 5-year disease-free survival were 89.2% and 88.1%, respectively. Patients frequently presented with large pelvic mass (>10 cm) and mild-to-moderate elevation of serological CA125 (≤200U/ mL). 60.7% of the cases at stage III/IV exhibited resistance to platinum-based chemotherapy; 37.69% of the tumors arose from endometriosis. On multivariate analysis, stage and chemoresistance were independent prognostic factors predictive for poorer survival. Survival at stage IC1 (surgical rupture) was comparable to that at stage IA (capsule intact), whereas survival at stage IC2/IC3 (rupture before surgery) was significantly worse than that at stage IA.OCCC shows distinct features compared to other epithelial ovarian cancers. FIGO stage and response to chemotherapy affect prognosis independently. Arising from endometriosis is not associated with better survival. Preoperative rupture rather than intraoperative rupture confers an adverse prognosis in otherwise stage IA disease.

Ankyrin repeat and single KH domain 1 (ANKHD1) drives renal cancer cell proliferation via binding to and altering a subset of miRNAs

Clear cell renal cell carcinoma (ccRCC) represents the most common kidney cancer worldwide. Increased cell proliferation associated with abnormal microRNA (miRNA) regulation are hallmarks of carcinogenesis. Ankyrin repeat and single KH domain 1 (ANKHD1) is a highly conserved protein found to interact with core cancer pathways in Drosophila; however, its involvement in RCC is completely unexplored. Quantitative PCR studies coupled with large-scale genomics data sets demonstrated that ANKHD1 is significantly up-regulated in kidneys of RCC patients when compared with healthy controls. Cell cycle analysis revealed that ANKHD1 is an essential factor for RCC cell division. To understand the molecular mechanism(s) utilized by ANKHD1 to drive proliferation, we performed bioinformatics analyses that revealed that ANKHD1 contains a putative miRNA-binding motif. We screened 48 miRNAs with tumor-enhancing or -suppressing activities and found that ANKHD1 binds to and regulates three tumor-suppressing miRNAs (i.e. miR-29a, miR-205, and miR-196a). RNA-immunoprecipitation assays demonstrated that ANKHD1 physically interacts with its target miRNAs via a single K-homology domain, located in the C terminus of the protein. Functionally, we discovered that ANKHD1 positively drives ccRCC cell mitosis via binding to and suppressing mainly miR-29a and to a lesser degree via miR-196a/205, leading to up-regulation in proliferative genes such as CCDN1. Collectively, these data identify ANKHD1 as a new regulator of ccRCC proliferation via specific miRNA interactions.

Tumor Enhancement on Dynamic CT: A Predictive Factor for Recurrence After Nephrectomy in Localized T1 Clear Cell Renal Cell Carcinoma

AIM

To investigate whether radiological parameters obtained on dynamic computed tomography (CT), especially those related to tumor enhancement, are predictive factors for recurrence after nephrectomy in localized stage T1 clear cell renal cell carcinoma (ccRCC).

MATERIALS AND METHODS

We retrospectively studied 88 patients with localized stage T1 ccRCC who underwent dynamic CT preoperatively. Seven patients had recurrent disease after surgery. Tumor attenuations were measured by placing a region of interest in the solid region. TA_pre and TA_neph were defined as the tumor attenuation values of the pre-contrast and nephrographic phase, respectively. The correlations between disease-free survival and clinicopathological factors, including the radiological parameter TA_neph - TA_pre (ΔTA_neph), were analyzed by Cox proportional hazards model or Kaplan-Meier method with the log-rank test.

RESULTS

Only ΔTA_neph was significantly and positively correlated with disease-free survival (p<0.05). Tumor size also tended to be negatively correlated with disease-free survival (p<0.1). The 5- and 10-year disease-free survival rates of the group with high ΔTA_neph (≥86 HU) were 97.4% and 97.4%, while those of the group with low ΔTA_neph (<86 HU) were 89.6% and 71.6%, respectively.

CONCLUSION

Tumor enhancement in the nephrographic phase of CT was a predictive factor for recurrence after nephrectomy in patients with localized stage T1 ccRCC.

Adipophilin as prognostic biomarker in clear cell renal cell carcinoma

Objective

To study the expression of adipophilin (PLIN2), a lipid storage-associated cell protein, in different subtypes of renal cell cancer and to elucidate its prognostic value.

Materials and Methods

Two-hundred-seventy-five patients with renal cell carcinoma (RCC) were included in this study. Immunohistochemistry with a polyclonal antibody to adipophilin was used on the tissue microarray (formalin-fixed, paraffin-embedded tissue) for detection of adipophilin. Median follow-up time was 91 (range 1-159) months in the whole cohort and 100 (1-159) months for patients with clear-cell RCC. Additional validation for adipophilin was performed using publicly available gene expression data for clear cell RCC from The Cancer Genome Atlas (TCGA).

Results

Adipophilin expression was detected in 14.3% of papillary RCC, in 0% of chromophobe RCC and in 58.7% of clear-cell RCC in the cytoplasm or at the membrane. Only membrane expression was correlated with other clinical parameters (pT-stage, pN-stage, R-status, sex) and showed a prognostic significance in univariate analysis with regard to overall survival of patients with clear cell subtype (HR 2.90, 95% CI 1.55-5.42, p=0.001), which failed significance on multivariate analysis. mRNA expression of PLIN2 on TCGA data using best selected cut-off was prognostically significant in both univariate (HR 1.76, 95% CI 1.28-2.42, p = 0.0005) and multivariate analyses (HR 1.46, 95% CI 1.05-2.04, p = 0.0257).

Conclusions

Adipophilin is a novel and still understudied prognostic biomarker in clear cell renal cell carcinoma which deserves further study.

Endometriosis-associated ovarian neoplasia

This article reviews the most relevant pathological and molecular features of ovarian tumours that are associated with endometriosis. Endometriosis is a common condition, affecting 5-15% of all women, and it has been estimated that 0.5-1% of cases are complicated by neoplasia. The most common malignant tumours in this setting are endometrioid adenocarcinoma and clear cell adenocarcinoma, each accounting for approximately 10% of ovarian carcinomas in Western countries. A minority of cases are associated with Lynch syndrome. These carcinomas are often confined to the ovaries at presentation in which case they have relatively favourable outcomes. However, high-stage tumours, particularly clear cell carcinomas, generally have a poor prognosis and this partly reflects relative resistance to current treatment. Histological diagnosis is straightforward in the majority of cases but some variants, for example endometrioid carcinomas with sex cord-like appearances or oxyphil cells, may create diagnostic difficulty. Similarly, clear cell carcinomas can show a range of architectural and cytological patterns that overlap with other tumours, both primary and metastatic, involving the ovaries. Endometriosis-associated borderline tumours are less common, and they often show mixed patterns of differentiation (seromucinous tumours). Atypical endometriosis may represent an intermediate step in neoplastic progression and some of these lesions demonstrate immunohistological and molecular alterations similar to those observed in endometriosis-related tumours. ARID1A mutations are relatively common in all of these tumours, but each has additional characteristic molecular alterations which are likely to be of increasing clinical relevance as targeted therapies are developed. Less is known of the pathogenesis of rarer endometriosis-associated ovarian tumours including endometrioid stromal sarcoma, mesodermal (Müllerian) adenosarcoma, and carcinosarcoma. This article also briefly reviews the issue of synchronous endometrioid carcinomas of the endometrium and the ovary, including the most recent developments on pathogenesis.

Transferrin receptor 1 upregulation in primary tumor and downregulation in benign kidney is associated with progression and mortality in renal cell carcinoma patients

The central dysregulated pathway of clear cell (cc) renal cell carcinoma (RCC), the von Hippel Lindau/hypoxia inducible factor-α axis, is a key regulator of intracellular iron levels, however the role of iron uptake in human RCC tumorigenesis and progression remains unknown. We conducted a thorough, large-scale investigation of the expression and prognostic significance of the primary iron uptake protein, transferrin receptor 1 (TfR1/CD71/TFRC), in RCC patients. TfR1 immunohistochemistry was performed in over 1500 cores from 574 renal cell tumor patient tissues (primary tumors, matched benign kidneys, metastases) and non-neoplastic tissues from 36 different body sites. TfR1 levels in RCC tumors, particularly ccRCC, were significantly associated with adverse clinical prognostic features (anemia, lower body mass index, smoking), worse tumor pathology (size, stage, grade, multifocality, sarcomatoid dedifferentiation) and worse survival outcomes, including after adjustments for tumor pathology. Highest TfR1 tissue levels in the non-gravid body were detected in benign renal tubule epithelium. Opposite to TfR1 changes in the primary tumor, TfR1 levels in benign kidney dropped during tumor progression and were inversely associated with worse survival outcomes, independent of tumor pathology. Quantitative measurement of TfR1 subcellular localization in cell lines demonstrated mixed cytoplasmic and membranous expression with increased TfR1 in clusters in ccRCC versus benign renal cell lines. Results of this study support an important role for TfR1 in RCC progression and identify TfR1 as a novel RCC biomarker and therapeutic target.

Somatic mutation profiles of clear cell endometrial tumors revealed by whole exome and targeted gene sequencing

BACKGROUND

The molecular pathogenesis of clear cell endometrial cancer (CCEC), a tumor type with a relatively unfavorable prognosis, is not well defined. We searched exome-wide for novel somatically mutated genes in CCEC and assessed the mutational spectrum of known and candidate driver genes in a large cohort of cases.

METHODS

We conducted whole exome sequencing of paired tumor-normal DNAs from 16 cases of CCEC (12 CCECs and the CCEC components of 4 mixed histology tumors). Twenty-two genes-of-interest were Sanger-sequenced from another 47 cases of CCEC. Microsatellite instability (MSI) and microsatellite stability (MSS) were determined by genotyping 5 mononucleotide repeats.

RESULTS

Two tumor exomes had relatively high mutational loads and MSI. The other 14 tumor exomes were MSS and had 236 validated nonsynonymous or splice junction somatic mutations among 222 protein-encoding genes. Among the 63 cases of CCEC in this study, we identified frequent somatic mutations in TP53 (39.7%), PIK3CA (23.8%), PIK3R1 (15.9%), ARID1A (15.9%), PPP2R1A (15.9%), SPOP (14.3%), and TAF1 (9.5%), as well as MSI (11.3%). Five of 8 mutations in TAF1, a gene with no known role in CCEC, localized to the putative histone acetyltransferase domain and included 2 recurrently mutated residues. Based on patterns of MSI and mutations in 7 genes, CCEC subsets molecularly resembled serous endometrial cancer (SEC) or endometrioid endometrial cancer (EEC).

CONCLUSION

Our findings demonstrate molecular similarities between CCEC and SEC and EEC and implicate TAF1 as a novel candidate CCEC driver gene. Cancer 2017;123:3261-8. © 2017 American Cancer Society.