Application of interpretable machine learning algorithms to predict distant metastasis in ovarian clear cell carcinoma.

BACKGROUND: Ovarian clear cell carcinoma (OCCC) represents a subtype of ovarian epithelial carcinoma (OEC) known for its limited responsiveness to chemotherapy, and the onset of distant metastasis significantly impacts patient prognoses. This study aimed to identify potential risk factors contributing to the occurrence of distant metastasis in OCCC. METHODS: Utilizing the Surveillance, Epidemiology, and End Results (SEER) database, we identified patients diagnosed with OCCC between 2004 and 2015. The most influential factors were selected through the application of Gaussian Naive Bayes (GNB) and Adaboost machine learning algorithms, employing a Venn test for further refinement. Subsequently, six machine learning (ML) techniques, namely XGBoost, LightGBM, Random Forest (RF), Adaptive Boosting (Adaboost), Support Vector Machine (SVM), and Multilayer Perceptron (MLP), were employed to construct predictive models for distant metastasis. Shapley Additive Interpretation (SHAP) analysis facilitated a visual interpretation for individual patient. Model validity was assessed using accuracy, sensitivity, specificity, positive predictive value, negative predictive value, F1 score, and the area under the receiver operating characteristic curve (AUC). RESULTS: In the realm of predicting distant metastasis, the Random Forest (RF) model outperformed the other five machine learning algorithms. The RF model demonstrated accuracy, sensitivity, specificity, positive predictive value, negative predictive value, F1 score, and AUC (95% CI) values of 0.792 (0.762-0.823), 0.904 (0.835-0.973), 0.759 (0.731-0.787), 0.221 (0.186-0.256), 0.974 (0.967-0.982), 0.353 (0.306-0.399), and 0.834 (0.696-0.967), respectively, surpassing the performance of other models. Additionally, the calibration curve's Brier Score (95%) for the RF model reached the minimum value of 0.06256 (0.05753-0.06759). SHAP analysis provided independent explanations, reaffirming the critical clinical factors associated with the risk of metastasis in OCCC patients. CONCLUSIONS: This study successfully established a precise predictive model for OCCC patient metastasis using machine learning techniques, offering valuable support to clinicians in making informed clinical decisions.

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.

PURE vs. mixed clear cell ovarian carcinomas: Is there any impact on survival?

OBJECTIVE: Our primary aim in this study is to define the clinical characteristics of patients with clear-cell ovarian carcinoma and evaluate the prognostic factors affecting survival. STUDY DESIGN: Records of 85 patients, operated between 2000 and 2018, for an adnexal mass and whose final pathology reported clear cell ovarian carcinoma were reviewed. The study considered demographic data, clinical characteristics of the patients, as well as pure and mixed-type clear cell histology. The patients' follow-up time, disease-free and overall survival recorded. The primary outcomes were disease-free survival (DFS) and overall survival (OS). RESULTS: The median age of the patients at diagnosis was 52. In 64.7 % of the cases, clear cell histology was pure, while the others (35.3 %) were mixed. Patients with ovarian endometriosis constituted 27.1 % of the whole population. The median OS for the entire population was 92 months (95 %CI:72-124). On univariate and multivariate analyses, advanced age was found to have a significant independent impact on OS and DFS (p < 0.05) and, was associated with a worse prognosis. Also, the multivariate analyses showed that the presence of endometriosis has a significant independent impact on OS (p < 0.05). When examining the relationship between the histological origin (mixed vs. pure) and 5-year survival, the mixed type showed longer OS and DFS rates (76.8 % vs. 69.8 %, 61.5 % vs. 53.8 %), the difference was not statistically significant (p > 0.05). CONCLUSION: This retrospective study showed that although mixed type histological origin was associated with higher OS and DFS rates compared to pure type in patients with CCOC, the difference was not statistically significant. Advanced age and the presence of endometriosis was found to have a significant independent effect on OS and DFS and was associated with a worse prognosis. Overall, this study provides useful insights into the clinical characteristics of patients with CCOC and identifies important prognostic factors affecting survival.

Pulmonary salivary gland tumor-hyalinizing clear cell carcinoma: a literature review.

Primary pulmonary hyalinizing clear cell carcinoma (HCCC) is a very rare lung tumor that accounts for less than 0.09% of all primary lung tumors and has no specific epidemiology. The correct diagnosis requires imaging, laboratory, pathological, immunohistochemical, and molecular examination. The most typical feature of pulmonary HCCC is the clear cell component with clear stroma. In addition, the fusion gene EWSR1::ATF1 due to t(12;22)(q13;q12) is essential for the pathological diagnosis of pulmonary HCCC. The main treatment for pulmonary HCCC is surgery. This review focus on the pathological features, immunohistochemical examination, mutation analysis and treatment of pulmonary HCCC.

Recurrent GATA3 P409Afs*99 Frameshift Extension Mutations in Sweat-gland Carcinoma With Neuroendocrine Differentiation.

Sweat-gland carcinoma with neuroendocrine differentiation (SCAND) was recently proposed as a new cutaneous adnexal neoplasm with neuroendocrine differentiation; however, its genetics are not well known. Herein, we performed clinicopathologic and genetic analyses of 13 SCAND cases and 5 control cases of endocrine mucin-producing sweat gland carcinoma (EMPSGC). The SCAND group included 11 males and 2 females with a median age of 68 years (range, 50 to 80 y). All SCAND lesions occurred in the ventral trunk or genital area. Of the 13 SCAND cases, 9 and 5 exhibited lymph node and distant metastases, respectively. Three (23.1%) patients with SCAND died of the disease. In contrast, neither metastasis nor mortality was confirmed in the EMPSGC cases. Immunoexpression of the androgen receptor, c-Myb, and MUC2 was limited in SCAND, whereas EMPSGC frequently expressed these immunomarkers. GATA3 P409Afs*99 extension mutations were detected in 7 (53.8%) of the 13 SCAND cases, using Sanger or panel sequencing. All 7 SCAND cases with GATA3 mutations were located in the genital, inguinal, or lower abdominal regions, whereas 5 of the other 6 SCAND cases were located in the anterior upper to mid-trunk. No GATA3 mutations were detected in the EMPSGC cases (0/5, 0%). These clinicopathologic and genetic findings support SCAND as a tumor entity distinguishable from EMPSGC. In addition, the characteristic frameshift extension mutations in GATA3 contribute to the establishment of the tumor-type concept of SCAND.

Trichorhinophalangeal Syndrome Type 1 Immunohistochemical Expression in Carcinomas of Gynecologic Origin.

Trichorhinophalangeal syndrome type 1 (TRPS1) is a new reportedly sensitive and specific immunohistochemical marker for carcinomas of breast origin, including triple-negative (estrogen receptor, progesterone receptor, and HER2) tumors. In our practice, we have observed a subset of cases of nonmammary carcinomas that are positive for TRPS1, with higher frequency in cytology effusion samples with metastatic gynecologic malignancies. This study aimed to evaluate the expression of TRPS1 in a large tissue cohort of Müllerian carcinomas. We retrospectively retrieved 105 cases of formalin-fixed paraffin-embedded gynecologic tumors from our surgical pathology archives. Cases corresponded to tumors of tubo-ovarian (17 high-grade serous carcinomas, 3 low-grade serous carcinomas, 2 clear cell carcinomas, and 8 endometrioid adenocarcinomas), endometrial (25 endometrioid adenocarcinomas, 8 serous carcinomas, 6 clear cell carcinomas, 12 carcinosarcomas, 1 dedifferentiated carcinoma, and 1 mesonephric-like adenocarcinoma), cervical (6 human papillomavirus [HPV]-associated squamous cell carcinomas [SCCs], 11 HPV-associated endocervical adenocarcinomas, and 2 HPV-independent gastric-type endocervical adenocarcinomas), and vulvar (2 HPV-independent SCCs and 1 HPV-associated SCC) origins. Immunohistochemistry for TRPS1 was performed in whole tissue sections and assessed for positivity (≥5% of nuclear labeling), distribution (focal: 5% to 49%, diffuse: 50% to 100%), and intensity (1+, 2+, 3+) in tumor cells. Positive TRPS1 staining was observed in 51.4% (54/105) of cases. Most tumors (64.8%) demonstrated diffuse labeling, while focal in 35.2%. Among positive cases, the intensity was predominantly 1+ (57.4%), followed by 2+ (33.3%) and 3+ (9.2%). Tumors with a high percentage of positivity overall consisted of tubo-ovarian (70%) and endometrial carcinomas (58.4%). TRPS1 immunostain is often expressed in gynecologic carcinomas. Awareness of this phenomenon is crucial when evaluating challenging cases in which the differential diagnosis includes a malignancy of breast origin, to avoid misclassification of the primary site.

A comprehensive analysis of essential meiotic endonuclease 1 to prognosis and immune infiltration in kidney renal clear cell carcinoma.

OBJECTIVE: Clear cell renal cell carcinoma (ccRCC) is the most common type of cancer, and its molecular pathogenesis is unclear. In this study, we investigated the prognostic value of essential meiotic endonuclease 1 (EME1) in kidney renal clear cell carcinoma (KIRC). MATERIALS AND METHODS: We downloaded the RNA-Seq expression of 526 KIRC tissues and 72 normal tissues from the TCGA database and the corresponding clinical data. The gene expression profiles associated with four clear cell renal cell carcinomas were downloaded from the GEO database for analysis. The expression of EME1 in clear renal cell carcinoma and its correlation with the clinical baseline data were analyzed. Kaplan-Meier survival curve analysis was performed to assess the relationship between EME1 and patient survival. Enrichment analysis was performed to elucidate the possible functions of EME1. We also analyzed the relationship between the EME1 expression and immune infiltration through TIMER2.0 and TISIDB online databases as well as the relationship between EME1 and common immune checkpoints. RESULTS: EME1 was identified as a risk factor for overall survival in clear cell renal cell carcinoma with a hazard ratio of 3.201 (95% confidence interval: 2.430-4.215; p < 0.001). EME1 was highly expressed in KIRC compared to that in normal tissues (p < 0.001) and in the worse TNM stages and late stages (stage 3/4) (p < 0.001). High EME1 expression was strongly associated with the advanced T stage (p = 0.003), advanced N stage (p = 0.002), and advanced M stage (p = 0.006). Research data on KIRC were simultaneously collected and analyzed from the GEO database, including GSE40435, GSE53000, GSE68417, and GSE53757. EME1 predicted the survival status in KIRC patients (AUC = 0.62). We further established a nomogram including the correlation between the high and low EME1 expression, and EME1 was found to contribute to the prediction of the probability of patient survival with a c-index = 0.796. Kaplan-Meier analysis revealed a lower likelihood of survival with a high EME1 expression (p < 0.001). In addition, further bioinformatics analysis suggested that EME1 may be associated with the extent of immune infiltration in KIRC. CONCLUSIONS: An increased expression of EME1 in KIRC is thus associated with advanced clinicopathological features, possibly acting as a potential biomarker of poor prognosis in KIRC.

Significantly Higher 68 Ga-FAPI Than 18 F-FDG Uptake by Hidradenocarcinoma of Head and Neck on PET/CT.

ABSTRACT: Hidradenocarcinoma is quite rare in clinical practice. Herein, we describe the 68 Ga-FAPI and 18 F-FDG PET/CT findings of hidradenocarcinoma of the head and neck in a 75-year-old man. In the present case, the primary tumor and secondary lesions showed intense accumulation of 68 Ga-FAPI but only slight 18 F-FDG uptake. This case demonstrates that 68 Ga-FAPI PET/CT might be used as a helpful tool for evaluating hidradenocarcinoma.

Ovarian clear cell carcinoma with uterine intramural recurrence: Case report of ovarian clear cell carcinoma with fertility sparing treatment.

OBJECTIVE: Ovarian clear cell carcinoma has a poor prognosis in comparison with other pathological types of epithelial ovarian carcinoma. It also has relative resistance to first-line platinum-based chemotherapy with a great risk of recurrence. CASE REPORT: We report a case of recurrent ovarian clear cell carcinoma status after left salpingo-oophorectomy (fertility-sparing debulking operation) and six courses of adjuvant chemotherapy (paclitaxel (175 mg/m2)/carboplatin (AUC 6)). However, two years after diagnosis, elevated CA-125 accompanied by an intrapelvic mass was noted. Uterine intramural recurrence was found during the second laparotomy. She was treated with right salpingo-oophorectomy and abdominal hysterectomy combined with systemic chemotherapy administration (paclitaxel (175 mg/m2)/carboplatin (AUC 6)) and maintenance therapy (bevacizumab (7.5 mg/kg)). There was no other recurrence until one and a half years postoperatively, and the patient was tumor free with regular follow-up. CONCLUSION: In young patients with stage I ovarian clear cell carcinoma, fertility-sparing surgery was considered. Most patients will suffer from tumor recurrence, and also intrauterine recurrence rarely happen.

The impact of lymphadenectomy on the survival outcomes of ovarian clear cell carcinoma: A retrospective study of the SEER database and Chinese registry.

BACKGROUND: Ovarian clear cell carcinoma (OCCC) is a rare pathological type of ovarian cancer with a poor prognosis, and lymphadenectomy is controversial in patients with OCCC. The objective of this study was to evaluate the impact of lymphadenectomy on the prognosis of patients with OCCC. METHODS: In this retrospective study, we collected data from the Surveillance, Epidemiology and End Results (SEER) database and institutional registries in China. The SEER cohort included 1777 women diagnosed with OCCC between 2010 and 2019, while the Chinese cohort included 199 women diagnosed between April 2004 and April 2021. Recurrence-free survival (RFS) and overall survival (OS) were studied using Kaplan-Meier curve and Cox regression analysis. We also employed propensity score matching (PSM) to adjust for baseline imbalances between the lymphadenectomy group and the no-lymphadenectomy group. RESULTS: Multivariate cox regression analysis showed that lymphadenectomy was not associated with better overall survival (OS) in either early (hazard ratio [HR] 0.84[0.50-1.43], p = 0.528) or advanced (HR 0.78[0.50-1.21], p = 0.270) patients in the SEER cohort after PSM. Additionally, in the Kaplan-Meier curve analysis, lymphadenectomy did not significantly improve OS in both early (p = 0.28) and advanced (p = 0.49) patients in the SEER cohort after PSM. Similarly, in the Chinese cohort, lymphadenectomy had no significant effect on OS (early p = 0.22; advanced p = 0.61) or RFS (early p = 0.18; advanced p = 0.83) in both early and advanced patients. CONCLUSION: In completely homogeneous groups, lymphadenectomy in women diagnosed with OCCC had no effect on either recurrence-free survival or overall survival compared to patients without lymphadenectomy.

Hyalinizing Clear Cell Carcinoma in the Sphenoid Sinus.

ABSTRACT: A 39-year-old man presented with a 1-month history of headaches. Imaging revealed a mass with extensive destruction. T2-weighted imaging displayed mixture of low and sponge-like high intensities and also dark area, with FDG PET/CT showing uneven but intense accumulation. Biopsy confirmed EWSR1 rearrangement, and hyalinizing clear cell carcinoma (HCCC) was diagnosed. HCCC, recently renamed from clear cell carcinoma in the fifth edition of the World Health Organization Classification of Head and Neck Tumors, is a rare tumor. This case describes the features of T2-weighted imaging and FDG PET patterns in HCCC, possibly contributing to their consideration in the differential diagnosis.

The impact of lymphadenectomy on ovarian clear cell carcinoma: a systematic review and meta-analysis.

BACKGROUND: Ovarian clear cell carcinoma (OCCC) shares treatment strategies with epithelial ovarian cancer (EOC). Due to OCCC's rarity, there's a lack of prospective studies on its surgery, resulting in heterogeneous and limited existing data. This study aims to clarify the prognostic significance of lymphadenectomy in OCCC patients. METHODS: We systematically searched Web of Science, Scopus, PubMed, and Google Scholar until July 2023 for studies investigating lymphadenectomy's effects on OCCC patients. We calculated pooled hazard ratios (HR) with 95% confidence intervals (CI). This study is registered in PROSPERO (CRD42021270460). RESULTS: Among 444 screened articles, seven studies (2883 women) met inclusion criteria. Our analysis revealed that lymphadenectomy significantly improved disease-specific survival (DSS) (HR = 0.76, 95%CI = 0.60-0.95, P = 0.02) and disease-free survival (DFS) (HR = 0.58, 95%CI = 0.34-0.99, P = 0.05). However, it did not significantly affect overall survival (OS) (HR = 0.80, 95%CI = 0.60-1.06, P = 0.12) or progression-free survival (PFS) (HR = 0.95, 95%CI = 0.64-1.42, P = 0.79). Notably, some earlier studies reported no survival benefit, warranting cautious interpretation. CONCLUSION: Lymphadenectomy does not significantly enhance OS and PFS for OCCC but does improve DFS and DSS. Tailoring treatment to individual patient profiles is imperative for optimal outcomes. Precise preoperative or intraoperative lymph node metastasis detection is essential for identifying candidates benefiting from lymphadenectomy. Collaborative international efforts and an OCCC database are pivotal for refining future treatment strategies.

Clear cell carcinoma of the ovary: Clues for radiologists to perform a correct diagnosis.

Ovarian clear cell carcinoma (OCCC) is an uncommon high-grade primary epithelial ovarian cancer, covering about 10-12 % of all ovarian malignancies. It has a strong association with endometriosis. OCCC diagnosis, at advanced stages, has an aggressive biological behaviour, and the therapeutic strategies for ovarian OCCC are somehow different from other ovarian carcinomas. Therefore, early diagnosis of these tumours is of extreme importance. As some ovarian tumours subtypes have distinguishing features, it is possible to differentiate them based on their imaging characteristics, which can guide patient management and help the clinicians and pathologists in their diagnosis. A large mass on one side of the ovary that is mostly cystic, with a focal or multifocal irregular eccentric growing solid mural nodules or projections protruding into the cystic space, may suggest clear cell carcinoma of the ovary diagnosis. The solid nodules usually have an intermediate signal on T2-weighted images. The cystic component can be either single or multilocular, and the contents may contain protein or blood. CT scanning is still the preferred method for preoperative staging and postoperative restaging, and radiologists are crucial in identifying this type of tumour. We reviewed the imaging files of patients with surgically proven clear cell carcinoma at the specimens, and our findings agree with previous studies. This paper aims to perform a comprehensive revision of OCCC's radiological and clinic-pathological features and assist radiologists in recognizing OCCC and narrowing down the possibilities of differential diagnosis.

Clear Cell Adenocarcinoma of Urethra: Clinical and Pathologic Implications and Characterization of Molecular Aberrations.

PURPOSE: This study aimed to evaluate the molecular features of clear cell adenocarcinoma (CCA) of the urinary tract and investigate its pathogenic pathways and possible actionable targets. MATERIALS AND METHODS: We retrospectively collected the data of patients with CCA between January 1999 and December 2016; the data were independently reviewed by two pathologists. We selected five cases of urinary CCA, based on the clinicopathological features. We analyzed these five cases by whole exome sequencing (WES) and subsequent bioinformatics analyses to determine the mutational spectrum and possible pathogenic pathways. RESULTS: All patients were female with a median age of 62 years. All tumors were located in the urethra and showed aggressive behavior with disease progression. WES revealed several genetic alterations, including driver gene mutations (AMER1, ARID1A, CHD4, KMT2D, KRAS, PBRM1, and PIK3R1) and mutations in other important genes with tumor-suppressive and oncogenic roles (CSMD3, KEAP1, SMARCA4, and CACNA1D). We suggest putative pathogenic pathways (chromatin remodeling pathway, mitogen-activated protein kinase signaling pathway, phosphoinositide 3-kinase/AKT/mammalian target of rapamycin pathway, and Wnt/ß-catenin pathway) as candidates for targeted therapies. CONCLUSION: Our findings shed light on the molecular background of this extremely rare tumor with poor prognosis and can help improve treatment options.

Cell State of Origin Impacts Development of Distinct Endometriosis-Related Ovarian Carcinoma Histotypes.

Clear cell ovarian carcinoma (CCOC) and endometrioid ovarian carcinoma (ENOC) are ovarian carcinoma histotypes, which are both thought to arise from ectopic endometrial (or endometrial-like) cells through an endometriosis intermediate. How the same cell type of origin gives rise to two morphologically and biologically different histotypes has been perplexing, particularly given that recurrent genetic mutations are common to both and present in nonmalignant precursors. We used RNA transcription analysis to show that the expression profiles of CCOC and ENOC resemble those of normal endometrium at secretory and proliferative phases of the menstrual cycle, respectively. DNA methylation at the promoter of the estrogen receptor (ER) gene (ESR1) was enriched in CCOC, which could potentially lock the cells in the secretory state. Compared with normal secretory-type endometrium, CCOC was further defined by increased expression of cysteine and glutathione synthesis pathway genes and downregulation of the iron antiporter, suggesting iron addiction and highlighting ferroptosis as a potential therapeutic target. Overall, these findings suggest that while CCOC and ENOC arise from the same cell type, these histotypes likely originate from different cell states. This "cell state of origin" model may help to explain the presence of histologic and molecular cancer subtypes arising in other organs. SIGNIFICANCE: Two cancer histotypes diverge from a common cell of origin epigenetically locked in different cell states, highlighting the importance of considering cell state to better understand the cell of origin of cancer.

SLFN11 is a BRCA Independent Biomarker for the Response to Platinum-Based Chemotherapy in High-Grade Serous Ovarian Cancer and Clear Cell Ovarian Carcinoma.

BRCA1/2 mutations are robust biomarkers for platinum-based chemotherapy in epithelial ovarian cancers. However, BRCA1/2 mutations in clear cell ovarian carcinoma (CCC) are less frequent compared with high-grade serous ovarian cancer (HGSC). The discovery of biomarkers that can be applied to CCC is an unmet need in chemotherapy. Schlafen 11 (SLFN11) has attracted attention as a novel sensitizer for DNA-damaging agents including platinum. In this study, we investigated the utility of SLFN11 in HGSC and CCC for platinum-based chemotherapy. SLFN11 expression was analyzed retrospectively by IHC across 326 ovarian cancer samples. The clinicopathologic significance of SLFN11 expression was analyzed across 57 advanced HGSC as a discovery set, 96 advanced HGSC as a validation set, and 57 advanced CCC cases, all of whom received platinum-based chemotherapy. BRCA1/2 mutation was analyzed using targeted-gene sequencing. In the HGSC cohort, the SLFN11-positive and BRCA mutation group showed significantly longer whereas the SLFN11-negative and BRCA wild-type group showed significantly shorter progression-free survival and overall survival. Moreover, SLFN11-positive HGSC shrunk significantly better than SLFN11-negative HGSC after neoadjuvant chemotherapy. Comparable results were obtained with CCC but without consideration of BRCA1/2 mutation due to a small population. Multivariate analysis identified SLFN11 as an independent factor for better survival in HGSC and CCC. The SLFN11-dependent sensitivity to platinum and PARP inhibitors were validated with genetically modified non-HGSC ovarian cancer cell lines. Our study reveals that SLFN11 predicts platinum sensitivity in HGSC and CCC independently of BRCA1/2 mutation status, indicating that SLFN11 assessment can guide treatment selection in HGSC and CCC.

Clinical, Histopathological and Immunohistochemical Aspects of Digital Papillary Adenocarcinoma: A Case Report and Literature Review.

Digital papillary adenocarcinoma (DPA) is a rare malignant eccrine tumor. A 62-year-old female presented with a subcutaneous nodular 1.5cm-mass in the thumb. Macroscopically, a poorly circumscribed mass containing cystic and solid components was observed. Microscopically, epithelial neoplasm consisting of tubular-cystic structures with back-to-back arrangements was observed. The lining epithelium was composed of cuboidal/columnar cells with mild atypia, with micropapillary extensions. Immunohistochemistry revealed double-layered neoplastic epithelium containing two different types of cells: basaloid/myoepithelial and luminal. We recommend two out of vimentin, HMWCK, and D2-40 for myoepithelial/basaloid cells, also CK7 and EMA for luminal/columnar cells. As the tumor had infiltrated the surgical margins, the patient underwent axillary sentinel lymph node (SLN) dissection and re-excision with Mohs micrographic surgery (MMS). Two additional MMS stages were required due to suspicious surgical margin positivity in the frozen sections. The operation was continued despite the risk of loss of function. Upon examination of the permanent sections, we observed no tumors in the suspected positive foci. Additionally, no tumor was found in the surgical margins. No metastasis was detected in the sentinel lymph node. We have reached 300 reported cases of DPA in the literature. We discussed the histopathological and intraoperative diagnostic pitfalls of DPA with a literature review and our experience.

Practice patterns, time trends and quality of care of uterine cancer in Belgium: An analysis of the EFFECT database.

OBJECTIVES: To investigate the practice patterns and quality of care for uterine cancer on a national level in Belgium, including trends in practice over the period 2012-2016. METHODS: Quality indicators were measured using the EFFectiveness of Endometrial Cancer Treatment (EFFECT) database. Multivariable logistic mixed regression was used to test for associations between the quality indicators and year of diagnosis, adjusted for potential confounders and intra-cluster correlations. RESULTS: The EFFECT database includes 4178 patients diagnosed with uterine cancer in the period 2012-2016. Minimally invasive surgery (laparoscopic or robotic-assisted) was applied in 61.6% of patients who had surgery for clinical stage I endometrial carcinoma (EC), increasing from 52.9% in 2012 to 66.4% in 2016. At least pelvic lymph node staging was performed in 69.0% of patients with clinical stage I, high-grade EC; and in 63.9% of patients with clinical stage I-II serous carcinoma, clear cell carcinoma or carcinosarcoma. The latter increased from 48.8% in 2012 to 77.2% in 2016. Adjuvant radiotherapy (external beam and/or brachytherapy) was offered to 33.5% of patients who had surgery without lymph node staging for pathological stage I EC at high-intermediate or high risk of recurrence. Adjuvant chemotherapy was administered to 64.4% of patients with pathological stage III-IVA EC. CONCLUSIONS: Study results indicate an overall good quality of care for patients with uterine cancer in Belgium. Treatment areas with potential room for improvement include the use of minimally invasive surgery, comprehensive surgical staging and adjuvant therapy, which confirms the remaining controversies in uterine cancer treatment and the need for further research.