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.

Trends in survival of ovarian clear cell carcinoma patients from 2000 to 2015

Purpose

To analyze changes in survival outcomes in patients with ovarian clear cell carcinoma (OCCC) treated consecutively over a 16-year period using a population-based cohort.

Methods

We conducted a retrospective analysis of OCCC from 2000 to 2015 using data from the Surveillance, Epidemiology, and End Results (SEER) program. The ovarian cancer-specific survival (OCSS) and overall survival (OS) were analyzed according to the year of diagnosis. Joinpoint Regression Program, Kaplan-Meier analysis, and multivariate Cox regression analyses were used for statistical analysis.

Results

We included 4257 patients in the analysis. The analysis of annual percentage change in OCSS (P=0.014) and OS (P=0.006) showed that patients diagnosed in later years had significantly better outcomes compared to those diagnosed in early years. The results of the multivariate Cox regression analyses showed that the year of diagnosis was the independent prognostic factor associated with OCSS (P=0.004) and had a borderline effect on OS (P=0.060). Regarding the SEER staging, the OCSS (P=0.017) and OS (P=0.004) of patients with distant stage showed a significant trend toward increased, while no significant trends were found in the survival of patients with localized or regional stage diseases. Similar trends were found in those aged <65 years or those treated with surgery and chemotherapy. However, no statistically significant changes in the survival rate were found in those aged ≥65 years or those receiving surgery alone regardless of SEER stage during the study period.

Conclusions

Our study observed a significant increase in the survival outcomes in OCCC from 2000 to 2015, and patients aged <65 years and those with distant stage experienced a greater improvement in survival.

Rare but Still There: A Scoping Review on Endometriosis-Associated Ovarian Cancer

Endometriosis is a medical condition affecting at least up to 10% of women of reproductive age. This condition occurs when ectopic endometrial glands and stroma implant outside the uterus and there are several theories regarding the underlying origins of the disease. Endometriosis is one of the major causes of severe dysmenorrhoea, chronic pelvic pain and infertility. While endometriosis is generally a non-malignant condition, it rarely may transform into an invasive cancer, and increase the risk for epithelial ovarian cancer, notably endometrioid or clear cell ovarian cancer. Despite the increased risk, the mechanisms behind the development of endometriosis-associated ovarian cancer (EAOC) are not yet well understood. Recent investigations have delved into the intricate interplay between endometriosis and EAOC, exploring pathways involving oxidative stress, inflammation, hyperestrogenism, and the discovery of genetic mutations within endometriotic lesions that hint at a transition towards invasive carcinoma. Efforts have been made to identify intermediary lesions between endometriosis and EAOC, which may enable earlier detection of endometriosis at risk of malignant transformation or even prevention of the transformation altogether. However, given the rarity of this malignancy, there is still the risk of late or missed diagnosis, with the risk of inappropriate management being offered to the patient, and the higher risk of poor prognosis and increased morbidity and mortality. This scoping review aims to summarize existing data on EAOC, with a focus on endometrioid and clear cell histologic subtypes. It also provides insights into its identification, prognosis, and delineating management strategies, seeking to provide a holistic understanding of the complexities surrounding EAOC, facilitating further research and the development of more effective prevention and treatment approaches.

Case report: Malignant transformation of ovarian endometrioma during long term use of dienogest in a young lady

Endometriosis is a benign disease, which is also regarded as a precursor to ovarian malignancy. Dienogest is a progestin treatment for endometriosis with efficacy and tolerability. A 35-year-old Taiwanese lady with ovarian endometrioma had taken dienogest for the last 5 years. During sonographic follow-up, surgery was suggested owing to suspicious of malignant transformation of ovarian endometrioma. While she hesitated and turned to receive two cycles of oocyte retrieval because of nulliparity. Meanwhile, more papillary growth in the ovarian endometrioma with intratumor flow was found during follow-up. Laparoscopic enucleation was performed later, and pathology revealed clear cell carcinoma with peritoneal involvement, at least FIGO stage IIB. She then underwent debulking surgery to grossly no residual tumor and received adjuvant chemotherapy with no tumor recurrence in post-operative 17-months follow-up. Considering fertility preservation, conservative treatment of ovarian endometrioma is typically indicated for those women who have not yet completed childbearing. However, malignant transformation may still occur despite long-term progestin treatment. Therefore, careful image follow-up is still indispensable.

Mixed Mesonephric-like Adenocarcinoma, Clear Cell Carcinoma, and Endometrioid Carcinoma Arising from an Endometriotic Cyst

Mesonephric-like adenocarcinoma is a rare neoplasm of the uterine corpus and ovary. Unlike prototypical mesonephric adenocarcinoma of the uterine cervix, which is considered of Wolffian origin, recent evidence suggests that mesonephric-like adenocarcinoma is a Mullerian tumor associated with endometriosis. We report here on a 48-year-old woman with a mixed carcinoma of the ovary that consisted of mesonephric-like adenocarcinoma, clear cell carcinoma, and endometrioid carcinoma, arising from an endometriotic cyst. The mesonephric-like adenocarcinoma consisted of cuboidal cells with vesicular nuclei presenting with a tubular, ductal, papillary, and solid architecture forming nodules. Each component showed distinct immunophenotypes that were consistent with their morphology. The mesonephric-like adenocarcinoma showed diffuse positive staining for paired box 8 and GATA binding protein 3, and negative staining for estrogen and progesterone receptors. A p53 stain exhibited wild-type immunoreactivity. A complete loss of AT-rich interactive domain-containing protein 1A (ARID1A) expression was suggestive of an ARID1A mutation. Manual macrodissection and Sanger sequencing revealed identical KRAS and PIK3CA mutations in all three components. To the best of our knowledge, this is the first report of mesonephric-like adenocarcinoma combined with a clear cell carcinoma and endometrioid carcinoma, which supports the hypothesis that mesonephric-like adenocarcinoma is an endometriosis-associated neoplasm. The report also highlights a potential pitfall in diagnosing mesonephric-like adenocarcinoma combined with clear cell carcinoma.

Malignant Pericardial Tamponade Secondary to Ovarian Clear Cell Carcinoma

Malignant pericardial effusion is an uncommon metastatic manifestation of ovarian carcinoma. Few cases of ovarian serous carcinoma have been previously reported. Ovarian clear cell carcinoma is the second most common histologic subtype in East Asian countries and is a relatively rare in Western countries. Here, we report the case of cardiac tamponade secondary to Ovarian clear cell carcinoma. A 46-year-old woman with recurrent Ovarian clear cell carcinoma presented with worsening cough, palpitations, and shortness of breath during chemotherapy. Chest radiography and computed tomography confirmed a pleural effusion with cardiac tamponade. The patient underwent pericardial fenestration and drainage for cardiac tamponade. Pericardial fluid cytology showed malignant cells forming papillary and ball-like clusters with irregular stacking. The cells had a mirror ball-like appearance and collagenous stroma, in which a homogenous hyaline core was observed in the center of most tumor cell clusters. Based on these findings, a diagnosis of Ovarian clear cell carcinoma metastasis was made. She received palliative care and died 5 months after the operation without recurrent cardiac tamponade. This case suggests that cytological findings from pericardial effusion are useful in diagnosing Ovarian clear cell carcinoma metastasis.

Tissue factor pathway inhibitor 2: Current understanding, challenges, and future perspectives

AIM

Tissue factor pathway inhibitor 2 (TFPI2) is a structural homolog of tissue factor pathway inhibitor 1 (TFPI1). Since TFPI2 is a placenta-derived protein, dynamic changes in TFPI2 levels may be related to pregnancy-related diseases. Furthermore, TFPI2 has been reported to be a novel serum biomarker for detecting ovarian cancer, especially clear cell carcinoma (CCC). This review aims to summarize the current knowledge on the biological function of TFPI2, highlight the major challenges that remain to be addressed, and discuss future research directions.

METHODS

Papers published up to March 31, 2023 in the PubMed and Google Scholar databases were included in this review. We also provide novel complementary information to what is known about the action of TFPI2.

RESULTS

Since TFPI2 concentrations in the blood of pregnant women, preeclampsia patients, and cancer patients vary greatly, its pathophysiological functions have attracted attention. Downregulation of TFPI2, a tumor-suppressor gene, by hypermethylation may contribute to the progression of several cancers. On the other hand, TFPI2 overexpressed in CCC is a risk factor for the development of thrombosis, possibly through inhibition of plasmin activity. However, agreement on the biological function of TFPI2 is still lacking and there are many scientific questions to be addressed. In particular, the lack of international standardization for the quantification of TFPI2 concentrations makes it difficult for researchers and clinicians to evaluate, pool, and compare data from different studies across countries.

DISCUSSION

This review summarizes current understandings and challenges in TFPI2 research and discusses future perspectives.

Müllerian-Type Clear Cell Carcinoma of Donor Origin in a Male Patient with a Kidney Transplant: Ascertained by Molecular Testing

Clear cell carcinomas of Müllerian origin have a strong female predominance and only extremely rarely will arise within the kidney, presumably due to ectopic Müllerian embryogenesis. Herein, we report a unique case of metastatic Müllerian type clear cell carcinoma in a 37-year-old patient who had previously received a transplanted kidney from his father at age 11 (due to severe bilateral vesicoureteral reflux) and remained on chronic immunosuppression. The tumor was highly aggressive and demonstrated somatic mutations in NF2 and SETD2. Imaging of the transplanted kidney did not reveal any clear evidence of malignancy. However, targeted multigene sequencing and short tandem repeat testing revealed that the cancer was of donor origin, presumably from ectopic Müllerian tissue transplanted to the patient along with the kidney graft. The tumor was resistant to first-line therapy with a triple combination of carboplatin plus paclitaxel plus bevacizumab, as well as to second-line immunotherapy with nivolumab plus ipilimumab after tapering down the patient's immunosuppression. Despite the tumor being genetically distinct from the host, the use of immune checkpoint therapy with nivolumab plus ipilimumab did not yield a response. This unique case showcases the value of molecular testing in determining the tumor origin in patients with solid organ transplants who present with cancers of unknown primary. This can prompt the potential investigation of other recipients from the same donor.

18F-FDG PET/CT Versus 68Ga-PSMA-11 PET/CT in Evaluation of Distant Metastatic Disease in Recurrent Renal Cell Carcinoma

Prostate-specific membrane antigen (PSMA) expression has been observed in the neovasculature of various malignancies. We present a case of metastatic renal cell carcinoma (RCC) with comparative 18F-FDG PET/CT and 68Ga-PSMA-11 imaging in which FDG PET/CT failed to detect metastatic thyroid disease and showed less 18F-FDG-concentrating lesions at other sites, whereas 68Ga-PSMA-11 PET/CT identified metastatic thyroid disease and demonstrated intensely 68Ga-PSMA-11-expressing distant metastatic lesions. 68Ga-PSMA-11 PET/CT may be considered a potentially useful imaging technique in RCC to detect metastasis and to guide the choice of specific treatments, such as PSMA-based radionuclide therapy in patients with recurrent metastatic RCC.

Application of Ultrasound Scores (Subjective Assessment, Simple Rules Risk Assessment, ADNEX Model, O-RADS) to Adnexal Masses of Difficult Classification

BACKGROUND

Ultrasound features help to differentiate benign from malignant masses, and some of them are included in the ultrasound (US) scores. The main aim of this work is to describe the ultrasound features of certain adnexal masses of difficult classification and to analyse them according to the most frequently used US scores.

METHODS

Retrospective studies of adnexal lesions are difficult to classify by US scores in women undergoing surgery. Ultrasound characteristics were analysed, and masses were classified according to the Subjective Assessment of the ultrasonographer (SA) and other US scores (IOTA Simple Rules Risk Assessment-SRRA, ADNEX model with and without CA125 and O-RADS).

RESULTS

A total of 133 adnexal masses were studied (benign: 66.2%, n:88; malignant: 33.8%, n:45) in a sample of women with mean age 56.5 ± 7.8 years. Malignant lesions were identified by SA in all cases. Borderline ovarian tumors (n:13) were not always detected by some US scores (SRRA: 76.9%, ADNEX model without and with CA125: 76.9% and 84.6%) nor were serous carcinoma (n:19) (SRRA: 89.5%), clear cell carcinoma (n:9) (SRRA: 66.7%) or endometrioid carcinoma (n:4) (ADNEX model without CA125: 75.0%). While most teratomas and serous cystadenomas have been correctly differentiated, other benign lesions were misclassified because of the presence of solid areas or papillae. Fibromas (n:13) were better identified by SA (23.1% malignancy), but worse with the other US scores (SRRA: 69.2%, ADNEX model without and with CA125: 84.6% and 69.2%, O-RADS: 53.8%). Cystoadenofibromas (n:10) were difficult to distinguish from malignant masses via all scores except SRRA (SA: 70.0%, SRRA: 20.0%, ADNEX model without and with CA125: 60.0% and 50.0%, O-RADS: 90.0%). Mucinous cystadenomas (n:12) were misdiagnosed as malignant in more than 15% of the cases in all US scores (SA: 33.3%, SRRA: 16.7%, ADNEX model without and with CA125: 16.7% and 16.7%, O-RADS:41.7%). Brenner tumors are also difficult to classify using all scores.

CONCLUSION

Some malignant masses (borderline ovarian tumors, serous carcinoma, clear cell carcinoma, endometrioid carcinomas) are not always detected by US scores. Fibromas, cystoadenofibromas, some mucinous cystadenomas and Brenner tumors may present solid components/papillae that may induce confusion with malignant lesions. Most teratomas and serous cystadenomas are usually correctly classified.

p16 Immunohistochemical Expression in Nephrogenic Adenoma

Nephrogenic adenoma (NA) is a rare metaplastic entity commonly associated with a prior urothelial injury. Most are seen in the urinary bladder and a minority involve the urethra. In this study, we evaluated the expression of p16 as a surrogate marker of this entity and correlated it with clinical pathological parameters. A total of 17 cases of NA were retrospectively studied to assess the immunohistochemical expression of p16 and its value for the diagnosis of this entity.

Pure and mixed clear cell carcinoma of the endometrium: A molecular and immunohistochemical analysis study

BACKGROUND

Uterine clear cell carcinoma (CCC) consists of either pure clear cell histology but can also display other histological components (mixed uterine CCCs). In this study, the molecular and immunohistochemical background of pure and mixed uterine CCC was compared. Secondly, it was evaluated whether histological classification and molecular background affected clinical outcome.

METHODS

A retrospective multicenter study was performed comparing pure uterine CCCs (n = 22) and mixed uterine CCCs (n = 21). Targeted next-generation sequencing using a 12-gene targeted panel classified cases as polymerase-ε (POLE) mutated, microsatellite instable (MSI), TP53 wildtype or TP53 mutated. Immunohistochemistry was performed for estrogen receptor, progesterone receptor, L1 cell adhesion molecule, MSH6, and PMS2.

RESULTS

The following molecular subgroups were identified for pure and mixed uterine CCCs, respectively: POLE mutated 0% (0/18) and 6% (1/18); MSI in 6% (1/18) and 50% (9/18); TP53 wildtype in 56% (10/18) and 22% (4/18); TP53 mutated in 39% (7/18) and 22% (4/18) (p = 0.013). Patients with mixed CCCs had improved outcome compared to patients with pure CCCs. Frequent TP53 mutations were found in pure CCCs and frequent MSI in mixed CCCs, associated with clinical outcome.

CONCLUSION

Pure and mixed uterine CCCs are two entities with different clinical outcomes, which could be explained by different molecular backgrounds. These results underline the relevance of both morphological and molecular evaluation, and may assist in tailoring treatment.

Competing risk model for prognostic comparison between clear cell type and common type hepatocellular carcinoma: A population-based propensity score matching study

BACKGROUND

Clear cell type hepatocellular carcinoma (HCC) is an uncommon neoplasm with an ambivalent prognosis compared to common type HCC.

METHODS

First, patients with clear cell or common type HCC were enrolled from the Surveillance, Epidemiology, and End Results (SEER) database, and their demographic and clinical characteristics were identified. Next, overall survival (OS), disease-specific survival (DSS), and subgroup analysis of the two types of HCC were performed. Next, we utilized a competing risk model to focus on cancer-caused death. Finally, propensity score matching (PSM) was employed to reduce the confounding factors based on the histopathological type, and sensitivity analysis was conducted.

RESULTS

A total of 205 cases of clear cell type HCC and 29,954 cases of common type HCC were enrolled in our study. Patients with clear cell type HCC were older and predominantly female than those with common type HCC. OS and DSS were not significantly different between the two groups, and histopathological type was not a prognostic factor of HCC, as verified by the competing risk model. Patient characteristics adjusted by PSM and sensitivity analysis confirmed this conclusion. In subgroup analysis, patients with clear cell type HCC at grade III ~ IV and with lymph nodes metastasis had a better prognosis compared to common type HCC.

CONCLUSIONS

This study revealed that the prognosis of clear cell type HCC is similar to common type HCC. Tumor differentiation grade and status of lymph node metastasis affect the prognosis of HCC.

Nephrogenic Adenoma Arising From a Female Urethral Diverticulum: A Case Report and Potential Diagnostic Pitfalls

Nephrogenic adenoma is a benign lesion of the urothelial tract characterized by tubules surrounded by thick, hyalinized basement membranes. There is a great variety of architectural patterns within nephrogenic adenomas, including patterns that mimic malignancy, such as focal clear or hobnail cells, areas of significant nuclear atypia, mitosis, and isolated cystic changes. This represents a diagnostic pitfall, where a malignant lesion can be mistaken for a nephrogenic adenoma, leading to a delay in diagnosis and treatment that adversely affects the outcome. In this case report, we describe a nephrogenic adenoma arising in a female urethral diverticulum and discuss the differential diagnosis, which includes clear cell carcinomas, microcystic variant urothelial carcinomas, and Skene's gland cysts.

Screening for important risk factors for cancer-specific mortality in patients with localized clear cell renal carcinoma

Aim

To study the risk factors for cancer-specific mortality (CSM) among patients with localized clear cell renal carcinoma (LCCRC) in the Chinese population.

Methods

The clinical data of 1,376 LCCRC patients were postoperatively collected to analyze the correlations between CSM and multiple factors using Cox regression analysis. Receiver operating characteristic curves were constructed as per the screened risk factors to identify factors with optimal criticality judgment values, which were then used as the scoring standard for the stratification evaluation of LCCRC prognosis.

Results

The CSM rate was 5.6% (77/1,376 cases) and the median follow-up duration was 78.1 (60-105) months. Cox analysis revealed that age, tumor diameter, and nuclear grade were associated with CSM. The optimal criticality judgment values for age and tumor diameter using receiver operating characteristic curve analysis were 53 years and 5.8 cm, respectively. LCCRC prognosis divided into low-risk (≤ 2 points), intermediate-risk (3-4 points), and high-risk (5 points) showed CSM rates of 3.8%, 13.8%, and 58.3%, respectively, among patients with more than 5 years of follow-up.

Conclusions

Age, tumor diameter, and nuclear grade were important risk factors for CSM in LCCRC patients. The scoring criteria including these three risk factors may be an important supplement to the prognostic model of LCCRC in the Chinese population.

Ligustrazine Inhibits the Migration and Invasion of Renal Cell Carcinoma

Ligustrazine is a Chinese herb (Chuanxiong) approved for use as a medical drug in China. Recent evidence suggests that ligustrazine has promising antitumor properties. Our preliminary results showed that ligustrazine could inhibit the growth of human renal cell carcinoma (RCC) cell lines. However, the complicated molecular mechanism has not been fully revealed. Therefore, the purpose of this study to investigate the mechanism of ligustrazine resistance in human RCC cells. Cell proliferation, migration, invasion, and colony-formation ability of RCC cells A498 were detected by MTT assay, clonal formation rates, and transwell chamber assay in vitro. The expression of epithelial-mesenchymal transition (EMT)-related proteins were analyzed using western blot test. The effect of ligustrazine on the growth of A498 cells in nude mice was investigated in vivo. Our results showed that ligustrazine could significantly inhibit the proliferation, migration, and invasion of A498 both in vivo and vitro. Western blot analysis showed that the expressions of EMT-related, N-cadherin, snail, and slug proteins were significantly decreased in A498 in the ligustrazine treatment group. This study indicated that ligustrazine could significantly inhibit the malignant biological behaviors of RCC cell lines, possibly by inhibiting the EMT process.

Case report: Durable response after pembrolizumab in combination with radiation - induced abscopal effect in platinum - refractory metastatic endometrial clear cell carcinoma

Advanced endometrial clear cell carcinoma (CCC) tends to have poor prognosis owing to aggressive clinical behavior and poor response to conventional chemotherapy. Herein, we report a case of platinum-refractory recurrent ECCC successfully treated with the combination of pembrolizumab, localized radiotherapy and a few cycles of chemotherapy with an extremely durable response even after cessation of immunotherapy for 3 years at the time of publication.

Cancer-Specific miRNAs Extracted from Tissue-Exudative Extracellular Vesicles in Ovarian Clear Cell Carcinoma

Ovarian clear cell carcinomas (OCCs) arise from endometriotic cysts that many women develop. Biomarkers for early OCC detection need to be identified. Extracellular vesicles have attracted attention as biomarker carriers. This study aims to identify cancer-specific miRNAs as novel OCC biomarkers using tissue-exudative extracellular vesicles (Te-EVs). Te-EVs were collected from four patients with OCC on one side and a normal ovary on the other side. Microarray analysis was performed to identify cancer-specific miRNAs in Te-EVs. Serum samples obtained before and after surgery from patients with OCC and atypical endometrial hyperplasia (AEH) (controls) were compared using real-time PCR to examine changes in the detected EV miRNA levels. Thirty-seven miRNAs were >2-fold upregulated on the OCC side compared with the normal ovarian side. We selected 17 miRNAs and created specific primers for 12 of these miRNAs. The levels of six EV miRNAs were significantly decreased in postoperative OCC serum compared to those in preoperative OCC serum. In contrast, no significant change was observed between the pre and postoperative values in the control group. We identified OCC tissue-specific miRNAs in the EVs secreted by OCC tissues. These EV miRNAs have potential for use as biomarkers for the early diagnosis and detection of OCC.

Factors That Affect Survival Outcomes in Patients with Endometrial Clear Cell Carcinoma

Background: Clear cell carcinoma (CCC) is a rare aggressive histologic subtype of endometrial cancer with a high relapse rate. In the present study, we sought to evaluate the prognostic factors of disease relapse and overall survival. Methods: We conducted retrospective cohort studies that included endometrial CCC patients treated at our institution. Predictive variables of survival outcomes were evaluated considering factors that determine the survival of patients with endometrioid carcinoma. Results: Fifty-five patients with a median age of 68 years and a median follow-up period of 31 months were included in the present study. Recurrence-free and overall survival rates did not differ among patients with early-stage and advanced-stage disease (RFS HR 1.51 (95% CI 0.63, 3.61), OS HR 1.36 (0.56, 3.31)). Patients with upper abdominal metastases had significantly shorter progression-free and overall survival intervals (log-rank < 0.001). The Gehan-Breslow-Wilcoxon analysis indicated worse survival rates for patients with advanced disease (p = 0.040); however, the log-rank test that gave equal weight to all time points did not reveal significant differences (log-rank = 0.576). Conclusion: Clear cell carcinoma is an aggressive histologic subtype of endometrial cancer that seems to be moderately affected by known predictors of survival rates in endometrioid carcinoma patients, except for the disease stage. Further research is needed to evaluate whether the molecular profiling of these patients may help predict survival outcomes.

Diagnostic and Prognostic Biomarkers in Renal Clear Cell Carcinoma

Renal clear cell carcinoma (ccRCC) comprises over 75% of all renal tumors and arises in the epithelial cells of the proximal convoluted tubule. Molecularly ccRCC is characterized by copy number alterations (CNAs) such as the loss of chromosome 3p and VHL inactivation. Additional driver mutations (SETD2, PBRM1, BAP1, and others) promote genomic instability and tumor cell metastasis through the dysregulation of various metabolic and immune-response pathways. Many researchers identified mutation, gene expression, and proteomic signatures for early diagnosis and prognostics for ccRCC. Despite a tremendous influx of data regarding DNA alterations, gene expression, and protein expression, the incorporation of these analyses for diagnosis and prognosis of RCC into the clinical application has not been implemented yet. In this review, we focused on the molecular changes associated with ccRCC development, along with gene expression and protein signatures, to emphasize the utilization of these molecular profiles in clinical practice. These findings, in the context of machine learning and precision medicine, may help to overcome some of the barriers encountered for implementing molecular profiles of tumors into the diagnosis and treatment of ccRCC.

Upregulation of matrix metalloproteinase 14 (MMP14) is associated with poor prognosis in renal clear cell carcinoma-a bioinformatics analysis

Background

Matrix metalloproteinase 14 (MMP14) has been reported to be upregulated in some types of cancer and to promote cancer cell invasion and metastasis. However, the expression profile and functional role of MMP14 in kidney renal clear cell carcinoma (KIRC) remains unknown. This study investigated the association between MMP14 expression level and prognosis in KIRC.

Methods

The messenger RNA (mRNA) expression profile and clinical data (including T stage, N stage, M stage, pathologic stage, gender, race, age, histologic grade, serum calcium, hemoglobin) were obtained from The Cancer Genome Atlas (TCGA) and Genotype-Tissue Expression (GTEx) database. Protein expression was evaluated by immunohistochemistry in the Human Protein Atlas (HPA) database. Correlation analyses between MMP14 and all mRNAs in KIRC were batch calculated, and gene set enrichment analyses (GSEA) were then conducted of Disease Ontology (DO) terms and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways using R packages. Multivariate logistic regression analysis was used to explore the prognostic factors of KIRC patients.

Results

The gene expression of MMP14 was significantly upregulated in KIRC tissues when compared with the normal tissue (P<0.001). The predictive ability of MMP14 as a variable for predicting tumor and normal outcomes had certain accuracy based on the receiver operating characteristic (ROC) model [area under the curve (AUC) =0.881, confidence interval (CI): 0.844-0.917]. When compared with the normal kidney tissue, the protein expression of MMP14 in KIRC got an increased trend, but due to the limited sample size, the difference is not statistically significant (P>0.05). Survival analysis revealed that MMP14 was significantly associated with overall survival in KIRC (P=0.013). GSEA of DO terms indicated high expression of MMP14 was related to KIRC, and GSEA of KEGG pathways showed that MMP14 and its coexpressed genes were significantly positively correlated with pathways in cancer. Signaling pathway GSEA indicated the upregulation of MMP14 in KIRC may activate cancer pathways.

Conclusions

MMP14 may be associated with poor prognosis in KIRC and may be a potential prognostic marker for KIRC.

Magnetic resonance imaging and 18F-fludeoxyglucose positron emission tomography/computed tomography findings of retroperitoneal clear cell carcinoma with an unknown primary site: A case report

Herein, we report a case of retroperitoneal clear cell carcinoma (RCCC) with an unknown primary site that was confirmed via pathology. A 46-year-old man presented with low-grade fever, hyperhidrosis, and nightly fatigue that had occurred for the last 20 days. His weight had decreased significantly within the past 2 months (approximately 12 kg). On abdominal ultrasound, a mass was observed near the left renal hilum. In addition, enhanced magnetic resonance imaging (MRI) of the abdomen revealed a retroperitoneal nodular mass; however, no abnormalities in either kidney or adrenal glands were observed. 18F-fludeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) demonstrated an intensely FDG-avid retroperitoneal mass, the maximum standardized uptake value (SUVmax) was 19.6. On March 8, 2021, left retroperitoneal lesion resection, retroperitoneal lymph node dissection, and double kidney exploration were performed under general anesthesia. A post-operative pathological examination revealed Poorly differentiated clear cell carcinoma (left retroperitoneal) and metastatic lymph nodes. Immunohistochemical findings showed that the tumor originated from the kidney. At 6-month follow-up, reexamination of the patient revealed retroperitoneal lesion recurrence; however, no abnormalities were observable via enhanced computed tomography (CT) of both kidneys. To our knowledge, there have been no previous reports of RCCC of unknown origin.

A rare case of a clear cell carcinoma in a female urethral diverticulum

Introduction

Urethral clear cell carcinoma is rare and often arises from a urethral diverticulum and rarely from the Müllerian duct. However, an explanation for this correlation remains unknown.

Case presentation

We report the case of a 46-year-old woman who presented with hypermenorrhea. Magnetic resonance imaging revealed a papillary tumor in a cystic lesion in the dorsal urethra. We performed a robot-assisted radical cystourethrectomy and created an ileal conduit. Since pathological findings revealed microvascular and lymphovascular invasions around the urethra, adjuvant radiation therapy was administered. The patient showed no signs of recurrence or metastasis after treatment.

Conclusion

We report a case of clear cell carcinoma in a female urethral diverticulum originating from a Müllerian duct cyst. While postoperative radiation therapy has been shown to produce a good outcome in carcinoma cases similar to this one, we recommend that a radical cystourethrectomy be performed.

Primary Clear Cell Carcinoma of the Pancreas: A Rare Case Report

Most pancreatic carcinoma is ductal adenocarcinoma. Primary pancreatic clear cell carcinomas composed almost entirely of clear tumor cells are very rare. We present a case of a 72-year-old man with a pancreatic mass, which was detected on abdominal computed tomography (CT). He had no symptoms and no abnormal findings on physical examination; however, he had a history of hepatitis B, hepatitis C, and hepatocellular carcinoma. He had received anti-viral treatment and radiofrequency ablation twice until 2 years prior. One year prior, follow-up contrast-enhanced abdominal CT revealed a newly developed pancreatic mass. Laparoscopic radical antegrade modular pancreato-splenectomy was performed. An ill-defined white-to-tan firm solid mass was observed in the pancreas, approximately 4.3 cm in diameter. The tumor cells showed >95% clear cell features, with a large round to oval nuclei and abundant clear cytoplasms, and well-defined cell membranes. Immunohistochemical staining revealed that the tumor cells were positive for cytokeratin 7, cytokeratin 19, HNF-1β, MUC-1, and p53. We excluded the possibility of metastatic clear renal cell carcinoma, neuroendocrine carcinoma, perivascular epithelioid cell tumor, malignant melanoma, and sarcoma because of the negativity for vimentin, chromogranin, synaptophysin, and HMB45. Consequently, he was diagnosed as having primary clear cell carcinoma of the pancreas and was treated with postoperative radiotherapy. Two months later, abdominal CT was suspicious for local recurrence at the resection margin. Additional adjuvant FOLFIRINOX chemotherapy was carried out 12 times. The patient is still alive after his third radiofrequency ablation for the newly-developed hepatic mass. Immunohistochemical staining for MUC-1 and HNF-1β, as well as histologic feature is very helpful for the diagnosis of primary pancreatic clear cell carcinoma with imaging methods for metastasis exclusion.

Extra-renal renal cell carcinoma arising in the kidney proximity but without an identifiable renal primary - an intriguing dilemma: Report of three cases and review of the literature

We report three patients with extra-renal renal cell carcinomas (RCC) found in the renal proximity, but unattached to the kidney. None had a history of RCC or an identifiable primary renal neoplasm at the time of the diagnosis and on follow-up. The patients included two males and one female aged 57, 77 and 63 years, respectively. One carcinomas was found in the perirenal tissue adjacent to the adrenal, one involved the adrenal gland, and one was a retroperitoneal mass found within the lymph nodes. Two extra-renal RCCs represented clear cell RCCs and one was an unclassifiable RCC. No patient had evidence of metastases at presentation and disease progression during the follow-up. This report adds to the literature on this unusual clinical scenario and further supports the concept of extra-renal RCC, which is not a well-recognized clinical phenomenon. We also reviewed other similar reports documenting the absence of identifiable renal primaries in the setting of either disseminated metastatic disease or isolated distant metastases of presumed renal origin. Similarly, some carcinomas of apparent renal derivation have been also identified during a work-up of metastatic carcinomas of unknown primary. The aim of this study is to raise further awareness of this unusual and intriguing clinical scenario that currently lacks a definitive explanation and standardized therapy strategies. Establishing a correct diagnosis may allow treatment with specific targeted therapies in selected clinical cases.

Characterization of rare histological subtypes of ovarian cancer based on molecular profiling

OBJECTIVE

Pan-cancer analysis across The Cancer Genome Atlas has revealed the molecular profiles of major types of carcinomas. High-grade serous carcinomas (HGSCs) have been characterized; however, in ovarian cancer, the profile of carcinoma with minor histopathological changes remains unclear. This study aimed to perform the molecular profiling of rare malignant ovarian tumors, including non-epithelial tumors (NETs; germ cell tumors and sex cord tumors) and clear cell carcinoma (CCC), to determine how they differ from the major HGSCs.

METHODS

Sixty-nine malignant ovarian tumors surgically resected at the Shizuoka Cancer Center between January 2014 and March 2019 were classified based on their histopathological types. The germline and somatic mutations in these carcinomas, including NETs, were determined using next-generation sequencing. Gene expression analysis was performed to investigate the major pathways of drug resistance, which is a characteristic of CCC.

RESULTS

NETs harbored copy-neutral loss of heterozygosity, accompanied by a high homologous recombination deficiency score; germline mutations of PALB2 and BARD1 were identified in two patients with NET. In chemoresistant CCC, the epithelial-mesenchymal transition pathway was activated regardless of ABC transporter expression.

CONCLUSION

This study revealed some genomic characteristics of rare malignant ovarian tumors, including NETs and CCC.

Clear Cell Carcinoma (CCC) of the Cervix Is a Human Papillomavirus (HPV)-independent Tumor Associated With Poor Outcome: A Comprehensive Analysis of 58 Cases

Cervical clear cell carcinoma (CCC) is a rare human papillomavirus-independent adenocarcinoma. While recent studies have focused on gastric-type endocervical adenocarcinoma (GTA), little is known about CCC. A total of 58 (CCCs) were collected from 14 international institutions and retrospectively analyzed using univariable and multivariable methods and compared with 36 gastric-type adenocarcinomas and 173 human papillomavirus-associated (HPVA) endocervical adenocarcinoma (ECA) regarding overall survival (OS) and recurrence-free survival (RFS). Most cases were FIGO stage I (72.4%), with Silva C pattern of invasion (77.6%), and the majority were treated with radical surgery (84.5%) and adjuvant therapy (55.2%). Lymphovascular invasion was present in 31%, while lymph node metastasis was seen in 24.1%; 10.3% were associated with abdominopelvic metastases at the time of diagnosis; 32.8% had recurrences, and 19% died of disease. We did not find statistically significant differences in OS and RFS between CCC and GTA at 5 and 10 years (P=0.313 and 0.508, respectively), but there were significant differences in both OS and RFS between CCC and HPVA ECA (P=0.003 and 0.032, respectively). Also, OS and RFS in stage I clear cell and GTA were similar (P=0.632 and 0.692, respectively). Multivariate analysis showed that OS is influenced by the presence of recurrence (P=0.009), while RFS is influenced by the FIGO stage (P=0.025). Cervical CCC has poorer outcomes than HPVA ECA and similar outcomes to human papillomavirus-independent GTA. Oncologic treatment significantly influences RFS in univariate analysis but is not an independent prognostic factor in multivariate analysis suggesting that alternative therapies should be investigated.

Trends in the Incidence and Survival Rates of Primary Ovarian Clear Cell Carcinoma Compared to Ovarian Serous Carcinoma in Korea

Objective

To compare the incidence and survival rates of primary ovarian clear cell carcinoma (OCCC) and ovarian serous carcinoma (OSC) from a nationwide collected database.

Methods

We extracted information of patients with primary OCCC and OSC from the Korea Central Cancer Registry recorded between 1999 and 2018, including age at diagnosis and the Surveillance, Epidemiology, and End Results summary stage. Age-standardized incidence rates (ASRs) and annual percent changes (APCs) were calculated. Baseline characteristics and overall survival (OS) were compared between the OCCC and OSC groups.

Results

Overall, the incidence rate of primary OCCC increased markedly from 1999 (ASR, 0.16/100,000) to 2018 (0.76/100,000) (APC, 7.85%; P<0.0001). Patients with OCCC were significantly younger and had early-stage disease more frequently than those with OSC. Patients diagnosed with OCCC before the age of 50 showed better OS than those diagnosed after the age of 50 (P=0.0048). The 5-year OS of the OCCC group did not differ by study period [73.5% (1999–2008) vs. 75.4% (2009–2018), P=0.3187], whereas the 5-year OS of the OSC group improved from 54.4% to 58% (P=0.0003).

Conclusions

Our nationwide registry-based study demonstrated that the incidence of OCCC in Korea increased significantly from 1999 to 2018. Early-stage OCCC had a relatively good prognosis, but advanced-stage OCCC had a worse OS than advanced-stage OSC. Therefore, the development of optimal treatment strategies for OCCC is warranted.

Successful treatment of a patient with recurrent metastatic clear cell carcinoma of the uterine cervix

Clear cell carcinoma (CCC) of the uterine cervix is a rare gynecologic cancer that accounts for 4-9% of adenocarcinoma of the uterine cervix. Two types of uterine cervical CCCs are known: A type that is associated with in utero exposure to diethylstilbestrol (DES) and idiopathic type that is unrelated to DES exposure. Due to its rare incidence, the clinical behavior and pathological characteristics of CCCs are not fully described and treatment recommendations are not standardized. Moreover, only a few cases are reported on the recurrent metastatic CCCs and the results of various treatment trials are inconsistent. We present a case of successfully treated idiopathic metastatic CCC of the uterine cervix that recurred after concurrent chemoradiotherapy.

Predicting Long-Term Prognoses and Grading Platinum Sensitivity Using a Novel Progression-Free Interval Criterion in Ovarian Clear Cell Carcinoma: A Multi-Institutional Cohort Study

This large-scale study aimed to determine the long-term influences of potential prognostic predictors and progression-free interval (PFI) criteria for grading platinum-sensitivity in ovarian clear cell carcinoma (OCCC). We retrospectively reviewed the medical records of OCCC patients presenting at nine tertiary centres (1995−2015), and evaluated patient characteristics, therapeutic factors, clinical outcomes, and hazard ratios for disease progression and death. We enrolled 536 patients (median follow-up, 36.6 months) and developed newly defined distributions of PFIs (seven and 14 months) for grading platinum sensitivity. In the multivariate model, preoperative CA125 levels and chemo-response independently predicted early-stage progression-free survival (PFS) risk. Post-progression cytoreduction correlated with reduced mortality risk. No unfavourable outcomes were observed with respect to coexisting endometriosis, fertility-sparing strategies, or platinum-based regimens. A PFI of <7 months, the strongest predictor of both post-progression mortality and second relapse risks, correlated with chemo-resistance, advanced tumour stage, and shortened post-progression survival. Chemotherapy regimens commonly used in front-line or relapse settings were limited in improving prognoses, especially in the advanced-stage cohort. Clinical trials of novel targeted agents and/or innovative biomarkers for chemoresistance should be comprehensively investigated and offered early to advanced-stage patients or those with OCCC progression occurring within seven months after receiving chemotherapy.

Microtentacle Formation in Ovarian Carcinoma

BACKGROUND

The development of chemoresistance to paclitaxel and carboplatin represents a major therapeutic challenge in ovarian cancer, a disease frequently characterized by malignant ascites and extrapelvic metastasis. Microtentacles (McTNs) are tubulin-based projections observed in detached breast cancer cells. In this study, we investigated whether ovarian cancers exhibit McTNs and characterized McTN biology.

METHODS

We used an established lipid-tethering mechanism to suspend and image individual cancer cells. We queried a panel of immortalized serous (OSC) and clear cell (OCCC) cell lines as well as freshly procured ascites and human ovarian surface epithelium (HOSE). We assessed by Western blot β-tubulin isotype, α-tubulin post-translational modifications and actin regulatory proteins in attached/detached states. We studied clustering in suspended conditions. Effects of treatment with microtubule depolymerizing and stabilizing drugs were described.

RESULTS

Among cell lines, up to 30% of cells expressed McTNs. Four McTN morphologies (absent, symmetric-short, symmetric-long, tufted) were observed in immortalized cultures as well as ascites. McTN number/length varied with histology according to metastatic potential. Most OCCC overexpressed class III ß-tubulin. OCCC/OSC cell lines exhibited a trend towards more microtubule-stabilizing post-translational modifications of α-tubulin relative to HOSE. Microtubule depolymerizing drugs decreased the number/length of McTNs, confirming that McTNs are composed of tubulin. Cells that failed to form McTNs demonstrated differential expression of α-tubulin- and actin-regulating proteins relative to cells that form McTNs. Cluster formation is more susceptible to microtubule targeting agents in cells that form McTNs, suggesting a role for McTNs in aggregation.

CONCLUSIONS

McTNs likely participate in key aspects of ovarian cancer metastasis. McTNs represent a new therapeutic target for this disease that could refine therapies, including intraperitoneal drug delivery.

Acute Presentation of Large Size Clear Cell Ovarian Carcinoma as Double Torsed Ovarian Tumor

We report a 46-year-old patient who presented to the emergency department with complaints of acute abdominal pain, nausea, and vomiting. An abdominal CT scan revealed a large (207 × 155 × 182 mm) thin-walled inhomogeneous tumor connected to the uterus and right ovary. Emergency surgery laparotomy was performed. Inside the abdominal cavity, a 30 × 30 cm heterogenous, dark blue tumor in the right adnexa area, torsed two times, weighing 3700 g was found. Histological examination revealed right ovary clear cell carcinoma. We emphasize the rare nature of the histology and presentation of this case report. Ovarian clear cell carcinomas are relatively rare malignancies, presenting in 5 to 10% of ovarian malignant tumors in the west.

Hypermethylation of mitochondrial DNA facilitates bone metastasis of renal cell carcinoma

Kidney cancers including clear cell carcinoma (RCC) are identified with very vulnerable mitochondria DNA (mtDNA) and frequent epigenetic aberrations. Bone metastasis from RCC is prevalent and destructive. Bone marrow contains a quite hypoxic microenvironment that usually insitigate 50% of hypermethylation events in conferring a selective advantage for tumor growth. We hypothesized that hypermethylation of mtDNA in RCC cells would significantly contribute to bone metastatic tumor progression. Methylation-specific polymerase chain reaction assay (MSP) was adopted to measure the methylation status of D-loop region of mtDNA in 15 pairs of bone metastatic and primary RCC as well as tumor adjescent normal kidney tissues. mtDNA copy number was examined by the real-time quantitative polymerase chain reaction (qPCR). Western blotting analysis was used to measure the accumulation of several DNA methyltransferases (DNMTs) in the mitochondria and nucleus fractions of bone metastatic RCC cells. mRNA expression of mitochondria encoded genes was examined by RT-PCR. Reactive oxygen species (ROS), mitochondrial membrane potential and ATP content were measured using in vitro cells treated with de-methylation drug 5-Azacytidine (5-Aza). Non-invasive bioluminescent imaging was performed to monitor tumor occurrence in skeleton in mice. Our results showed that the D-loop region in bone metastatic tumor cells was markedly hypermethylated than those in primary RCC tumor cells, that is associated with a decreased mtDNA copy number and accumulation of DNMT1 in the mitochondria. The bone-tropism tumor colonization and progression of RCC cells was significantly suppressed by demethylating the D-loop region of mtDNA and reducing the intracellular level of ROS and ATP by 5-Aza treatment. In conclusion, our study provided a direct association between hypermethylation of mtDNA in RCC with bone metastastic tumor growth.

Influence of clear cell carcinoma on the post-hepatectomy prognosis of patients with hepatocellular carcinoma

Aim: The authors aimed to identify factors that independently influence the survival of patients with primary clear cell carcinoma of the liver (PCCCL). Methods: A total of 470 patients with hepatocellular carcinoma were retrospectively analyzed. Multivariate Cox analysis was used to identify potential factors associated with prognosis of PCCCL. Results: Patients with PCCCL showed significantly higher disease-free survival (DFS) and overall survival (OS) compared with patients with non-clear cell hepatocellular carcinoma. Multivariate analysis revealed that AFP level, tumor size, liver cirrhosis and portal vein tumor thrombosis were risk factors for DFS. Tumor size, capsule formation and Ki-67 were risk factors for OS. Satellite nodules acted as a protective factor for DFS and OS. Conclusion: PCCCL is associated with better prognosis in hepatocellular carcinoma. Tumor size and satellite nodules may be independent predictors of OS and DFS.

Novel Therapeutic Strategies for Refractory Ovarian Cancers: Clear Cell and Mucinous Carcinomas

Ovarian cancer has the worst prognosis among gynecological cancers. In particular, clear cell and mucinous carcinomas are less sensitive to chemotherapy. The establishment of new therapies is necessary to improve the treatment outcomes for these carcinomas. In previous clinical studies, chemotherapy with cytotoxic anticancer drugs has failed to demonstrate better treatment outcomes than paclitaxel + carboplatin therapy. In recent years, attention has been focused on treatment with molecular target drugs and immune checkpoint inhibitors that target newly identified biomarkers. The issues that need to be addressed include the most appropriate combination of therapies, identifying patients who may benefit from each therapy, and how results should be incorporated into the standard of care for ovarian clear cell and mucinous carcinomas. In this article, we have reviewed the most promising therapies for ovarian clear cell and mucinous carcinomas, which are regarded as intractable, with an emphasis on therapies currently being investigated in clinical studies.

Prognostic significance of the number of removed lymph nodes according to FIGO stage in ovarian clear cell carcinoma

A previous study by our group reported that removing a larger number of lymph nodes in patients with stage I ovarian clear cell carcinoma (OCCC) improved progression-free survival (PFS). The present study investigated whether clinical conditions, particularly the number of removed lymph nodes, are independent predictors of progression for stage II or higher OCCC and whether the significance of the number of removed lymph nodes differs according to FIGO stage for OCCC. A total of 113 patients with OCCC who had undergone surgery between January 1993 and December 2015 were retrospectively enrolled and the clinicopathological data were obtained from their medical records. Among patients with stage II or higher OCCC, PFS of those with no residual tumor or no lymph node metastasis was significantly better than that of those with residual tumor (P=0.023) or lymph node metastasis (P=0.035). Multivariate analysis revealed that no residual tumor was the only independent predictor for improved PFS of patients with stage II or higher. Regarding the number of removed lymph nodes, it did not significantly affect the PFS of patients with stage II or higher OCCC, whereas it improved the PFS of those with stage I, being an independent predictor of progression of stage I OCCC. In summary, although the number of removed lymph nodes was an independent predictor of progression for stage I OCCC, it was not for stage II or higher OCCC. The prognostic significance of the number of removed lymph nodes in OCCC may differ depending on the FIGO stage.

Clear cell carcinoma: a comprehensive literature review of 254 cases

This comprehensive literature review represents a summary of all cases of clear cell carcinoma (CCC) of the salivary glands that are documented in the literature. PubMed was used to collect available reports of CCC; 97 reports detailing 254 cases, published between 1983 and 2020, were retrieved. Clinically the tumor manifests most commonly as a painless mass or swelling on the palate, and the duration of symptoms prior to seeking care ranges from 1 week to 6 years. Local tumor recurrence was present in 18.8% of the cases. By histopathology, CCC shows a mixture of growth patterns including solid (25.1%), nested (78.6%), sheet-like (23.5%), cords (46.1%), and trabeculae (42.4%). Immunohistochemical studies are positive for one or more cytokeratins (99.1%), PAS (95.1%), EMA (77.8%), and p63 (96.3%), but negative for S-100 (96.3%), PASD (91.1%), SMA (91.0%), and calponin (95.1%). Molecular features were reported in 113 cases; 96.0% were positive for an EWSR1 rearrangement by EWSR1 break apart FISH testing and 14.8% were positive for the rearrangement EWSR1-ATF1 tested by qPCR or targeted RNA sequencing. Clinical patterns and genetic studies imply that this tumor is the extraosseous counterpart of clear cell odontogenic carcinoma, an intraosseous odontogenic tumor of the jaws.

Genomic Sub-Classification of Ovarian Clear Cell Carcinoma Revealed by Distinct Mutational Signatures

Ovarian clear cell carcinoma (OCCC) is characterized by dismal prognosis, partially due to its low sensitivity to standard chemotherapy regimen. It is also well-known for presenting unique molecular features in comparison to other epithelial ovarian cancer subtypes. Here, we aim to identify potential subgroups of patients in order to (1) determine their molecular features and (2) characterize their mutational signature. Furthermore, we sought to perform the investigation based on a potentially clinically relevant setting. To that end, we assessed the mutational profile and genomic instability of 55 patients extracted from the Gynecologic Cancer Database (DGCD) by using a panel comprised of 409 cancer-associated genes and a microsatellite assay, respectively; both are currently used in our routine environment. In accordance with previous findings, ARID1A and PIK3CA were the most prevalent mutations, present in 49.1% and 41.8%, respectively. From those, the co-occurrence of ARID1A and PIK3CA mutations was observed in 36.1% of subjects, indicating that this association might be a common feature of OCCC. The microsatellite instability frequency was low across samples. An unbiased assessment of signatures identified the presence of three subgroups, where "PIK3CA" and "Double hit" (with ARID1A and PIK3CA double mutation) subgroups exhibited unique signatures, whilst "ARID1A" and "Undetermined" (no mutations on ARID1A nor PIK3CA) subgroups showed similar profiles. Those differences were further indicated by COSMIC signatures. Taken together, the current findings suggest that OCCC presents distinct mutational landscapes within its group, which may indicate different therapeutic approaches according to its subgroup. Although encouraging, it is noteworthy that the current results are limited by sample size, and further investigation on a larger group would be crucial to better elucidate them.

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.

A DNA Damage Response Gene Panel for Different Histologic Types of Epithelial Ovarian Carcinomas and Their Outcomes

DNA damage response (DDR) is important for maintaining genomic integrity of the cell. Aberrant DDR pathways lead to accumulation of DNA damage, genomic instability and malignant transformations. Gene mutations have been proven to be associated with epithelial ovarian cancer, and the majority of the literature has focused on BRCA. In this study, we investigated the somatic mutation of DNA damage response genes in epithelial ovarian cancer patients using a multiple-gene panel with next-generation sequencing. In all, 69 serous, 39 endometrioid and 64 clear cell carcinoma patients were enrolled. Serous carcinoma patients (69.6%) had higher percentages of DDR gene mutations compared with patients with endometrioid (33.3%) and clear cell carcinoma (26.6%) (p < 0.001, chi-squared test). The percentages of DDR gene mutations in patients with recurrence (53.9 vs. 32.9% p = 0.006, chi-squared test) or cancer-related death (59.2 vs. 34.4% p = 0.001, chi-squared test) were higher than those without recurrence or living patients. In endometrioid carcinoma, patients with ≥2 DDR gene mutations had shorter PFS (p = 0.0035, log-rank test) and OS (p = 0.015, log-rank test) than those with one mutation or none. In clear cell carcinoma, patients with ≥2 DDR gene mutations had significantly shorter PFS (p = 0.0056, log-rank test) and OS (p = 0.0046, log-rank test) than those with 1 DDR mutation or none. In the EOC patients, somatic DDR gene mutations were associated with advanced-stage tumor recurrence and tumor-related death. Type I EOC patients with DDR mutations had an unfavorable prognosis, especially for clear cell carcinoma.

Clear Cell Carcinoma Arising in an Abdominal Wall Cesarean Section Scar: A Case Report With Description of Pathological and Molecular Features

Clear cell carcinoma is a clinically and biologically distinct type of carcinoma predominantly encountered in the ovary and endometrium. In the ovary, it is frequently associated with endometriosis, which is a well-known risk factor. Endometriosis has often been described in the abdominal wall of women who had a cesarean section; however, malignant transformation is a very rare event, occurring in <1% of cases. The authors report a case involving a 52-year-old woman with an abdominal wall nodule at a cesarean section scar. Radiology revealed a mass, measuring 8 cm in size, in the abdominal wall suggestive of a soft tissue tumor. After resection, histology revealed the presence of clear, eosinophilic, and hobnail cells, which, together with immunohistochemical and molecular findings, enabled the diagnosis of clear cell carcinoma of the abdominal wall. The present report describes the clinical, radiological, pathological, and molecular features of an unusual abdominal lesion that represents a rare but challenging diagnosis.

Preclinical Activity of Plitidepsin Against Clear Cell Carcinoma of the Ovary

BACKGROUND/AIM

To evaluate the antitumor effects of Plitidepsin against clear cell carcinoma (CCC) of the ovary.

MATERIALS AND METHODS

The expression of eEF1A2 in ovarian cancer was assessed by immunohistochemistry. Using ovarian CCC cell lines, the antitumor effect of Plitidepsin was assessed both in vitro and in vivo. By over-expressing or knocking down the eEF1A2 expression, we investigated the role of eEF1A2 in the sensitivity of CCC cells to Plitidepsin.

RESULTS

Immunoreactivity to eEF1A2 was observed in 76.2% of CCC, which was significantly higher than other histological subtypes of ovarian cancer. Plitidepsin exhibited significant antitumor activity toward chemonaive and chemoresistant CCC cells both in vitro and in vivo. Ectopic expression of eEF1A2 in CCC cells resulted in increased sensitivity to Plitidepsin. In contrast, eEF1A2 knockdown decreased sensitivity of CCC cells to plitidepsin.

CONCLUSION

Plitidepsin, a novel anti-cancer agent that targets eEF1A2, may be a promising agent for treating ovarian CCC.

PDK2 leads to cisplatin resistance through suppression of mitochondrial function in ovarian clear cell carcinoma

Ovarian clear cell carcinoma (CCC) exhibits an association with endometriosis, resistance to oxidative stress, and poor prognosis owing to its resistance to conventional platinum‐based chemotherapy. A greater understanding of the molecular characteristics and pathogenesis of ovarian cancer subtypes may facilitate the development of targeted therapeutic strategies, although the mechanism of drug resistance in ovarian CCC has yet to be determined. In this study, we assessed exome sequencing data to identify new therapeutic targets of mitochondrial function in ovarian CCC because of the central role of mitochondria in redox homeostasis. Copy number analyses revealed that chromosome 17q21‐24 (chr.17q21‐24) amplification was associated with recurrence in ovarian CCC. Cell viability assays identified an association between cisplatin resistance and chr.17q21‐24 amplification, and mitochondrion‐related genes were enriched in patients with chr.17q21‐24 amplification. Patients with high expression of pyruvate dehydrogenase kinase 2 (PDK2) had a worse prognosis than those with low PDK2 expression. Furthermore, inhibition of PDK2 synergistically enhanced cisplatin sensitivity by activating the electron transport chain and by increasing the production of mitochondrial reactive oxygen species. Mouse xenograft models showed that inhibition of PDK2 with cisplatin inhibited tumor growth. This evidence suggests that targeting mitochondrial metabolism and redox homeostasis is an attractive therapeutic strategy for improving drug sensitivity in ovarian CCC.

[A case report of tonsil clear cell carcinoma]

Clear cell carcinoma is a rare head and neck malignancy, which has a good prognosis. Its diagnosis requires a combination of histology, immunohistochemistry and molecular testing. We present a case of tonsil clear cell carcinoma, which was treated with extended tumor resection. The patient did not receive postoperative adjuvant therapy, and no recurrence or metastasis was found in the follow-up of 13 months.

PD-L1 Expressing Recurrent Clear Cell Carcinoma of the Vulva with Durable Partial Response to Pembrolizumab: A Case Report

Background

The optimal treatment and molecular landscape of recurrent clear cell carcinoma of the vulva (VCCC) are unknown. No reported data exist regarding the efficacy of anti-programmed death 1 (PD-1) immune checkpoint inhibition in VCCC. We report on a patient with chemotherapy-refractory recurrent VCCC, who was found to have high tumor programmed death-ligand 1 (PD-L1) combined positive score (CPS), and subsequently experienced a durable partial response (PR), after treatment with off-label fifth-line pembrolizumab.

Case Presentation

A forty-year-old Filipino woman presented to our center with recurrent VCCC that had progressed on multiple prior lines of cytotoxic chemotherapy. She had a large 25 cm fungating left groin tumor causing marked lower limb lymphedema, pain and limited mobility. PD-L1 CPS by immunohistochemistry was 45. She was treated with off-label pembrolizumab monotherapy and had a dramatic clinical, biochemical and radiological partial response. The progression-free survival of this patient's VCCC after treatment with pembrolizumab, defined as the time from initiation of pembrolizumab until disease progression (by Response Evaluation Criteria in Solid Tumors (version 1.1)), was 8 months. While receiving pembrolizumab, she was diagnosed with concurrent secondary myelodysplastic syndrome with excess blasts (MDS-EB), thought to be related to her prior exposure to multiple lines of cytotoxic chemotherapy. This eventually progressed to acute myeloid leukemia (AML), leading to her demise. Overall survival from time of initiation of pembrolizumab till death was 16 months.

Conclusion

Pembrolizumab was active in this patient with chemotherapy-refractory VCCC which harbored high PD-L1 CPS. Further studies to determine the role of immune check-point blockade in the treatment of VCCC are warranted.

Toward an understanding of tissue factor pathway inhibitor-2 as a novel serodiagnostic marker for clear cell carcinoma of the ovary

AIMS

Tissue factor pathway inhibitor (TFPI)-2 has recently emerged as a serodiagnostic marker for patients with epithelial ovarian cancer (EOC), especially clear cell carcinoma (CCC). This review discusses the biological properties of TFPI-2 and why serum levels are elevated in CCC patients.

METHODS

A comprehensive literature search was conducted in PubMed up until March, 2021.

RESULTS

TFPI-2 is a Kunitz-type protease inhibitor and negatively regulates the enzymatic activities, such as plasmin. TFPI-2 has been characterized as a tumor suppressor gene and was frequently downregulated through promoter hypermethylation in various human cancers. In contrast, TFPI-2 was overexpressed only in CCC. TFPI-2 may be involved in the pathophysiology of CCC, possibly through regulation of coagulation system, stabilization of extracellular matrix (ECM), and induction of intracellular signal transduction. TFPI-2 suppresses tissue factor-induced hypercoagulation in a hypoxic environment. TFPI-2, secreted by CCC cells, platelets, and adjacent vascular endothelial cells, may suppress tumor growth and invasion through ECM remodeling. Nuclear TFPI-2 may suppress matrix metalloproteinase production via transcription factors and modulate caspase-mediated cell apoptosis. CCC cells may upregulate the TFPI-2 expression to adapt to survival in the demanding environment. TFPI-2 is secreted by CCC cells and enters the systemic circulation, resulting in elevated blood levels.

DISCUSSION

Serum TFPI-2 reflects the overexpression of TFPI-2 in CCC tissues and is a potential serodiagnostic marker. Further research is needed to explore the expression, clinical significance, biological function, and potential mechanism of TFPI-2 in CCC.

Cardiac Tamponade as a Manifestation of Clear Cell Renal Cell Carcinoma

Some solid cancers (such as lung, breast, and esophageal cancer, and melanoma) can lead to pericardial effusion by metastatic spread, potentially provoking hemodynamic instability. Detection by echocardiography is therefore essential. Pericardiocentesis can help restore cardiac function and provide fluid for establishing an etiology through cytological, microbiological, and cellularity analysis. A 60-year-old woman with metabolic syndrome and obesity hypoventilation syndrome presented to the emergency department with dyspnea at rest. A chest X-ray showed cardiomegaly and massive left pleural effusion. Ultrasound findings were pericardial effusion with signs of cardiac tamponade. We performed pericardiocentesis, extracting 1000 mL of exudate, and thoracentesis, which confirmed the diagnosis of lymphocytic exudative effusion. A CAT (computerized tomography) scan of the chest, abdomen, and pelvis revealed a left kidney mass. A biopsy of the mass confirmed the diagnosis of clear cell renal cell carcinoma and a pleural biopsy revealed metastatic involvement. This report describes a rare presentation of cardiac tamponade due to clear cell renal cell carcinoma and discusses the pathogenesis, mechanisms, and prognosis of this condition.

Ovarian clear cell carcinoma with an immature teratoma component showing ARID1A deficiency and an identical PIK3CA mutation

We herein report a case of ovarian clear cell carcinoma with an immature teratoma component that exhibited aggressive behavior. A 47-year-old woman presented with abdominal distention, and computed tomography detected a cystic mass on the right ovary. The resected mass had mural nodules, most of which showed a pale-yellow appearance; some nodules had a heterogeneous cut surface with bright yellow and white areas. Histologically, the former nodules were composed of clear cell carcinoma, while the latter contained teratomatous tissues, such as immature skeletal muscle, adipose tissue, and enteric glands. The tumor was staged as pT1c. Despite adjuvant chemotherapy and additional lymph node dissection, she had local recurrence and multiple liver metastasis 6 months after the first surgery. The disease rapidly progressed, and she died 9 months after the first surgery. Clear cell carcinoma and immature teratoma both showed ARID1A deficiency and an identical PIK3CA mutation, which suggested their clonal relationship.

New Pathological and Clinical Insights in Endometrial Cancer in View of the Updated ESGO/ESTRO/ESP Guidelines

Simple Summary

Histopathological classification of endometrial carcinoma has evidenced two main groups with different biological behavior: low-grade (G1–G2) and high-grade (G3) endometrial tumors. Moreover, the Cancer Genome Atlas (TCGA) documented four molecular categories with distinct clinical, pathologic, and molecular features: POLE/ultramutated (7% of cases) microsatellite instability (MSI)/hypermutated (28%), copy-number low/endometrioid (39%), and copy-number high/serous-like (26%). The aim of the present paper is to review all endometrial carcinoma histotypes in light of the morphological and molecular prognostic TCGA groups.

Abstract

Endometrial carcinoma represents the most common gynecological cancer in Europe and the USA. Histopathological classification based on tumor morphology and tumor grade has played a crucial role in the management of endometrial carcinoma, allowing a prognostic stratification into distinct risk categories, and guiding surgical and adjuvant therapy. In 2013, The Cancer Genome Atlas (TCGA) Research Network reported a large scale molecular analysis of 373 endometrial carcinomas which demonstrated four categories with distinct clinical, pathologic, and molecular features: POLE/ultramutated (7% of cases) microsatellite instability (MSI)/hypermutated (28%), copy-number low/endometrioid (39%), and copy-number high/serous-like (26%). In the present article, we report a detailed histological and molecular review of all endometrial carcinoma histotypes in light of the current ESGO/ESTRO/ESP guidelines. In particular, we focus on the distribution and prognostic value of the TCGA groups in each histotype.