Background: The Korean Society for Cytopathology introduced a digital proficiency test (PT) in 2021. However, many doubtful opinions remain on whether digitally scanned images can satisfactorily present subtle differences in the nuclear features and chromatin patterns of cytological samples. Methods: We prepared 30 whole-slide images (WSIs) from the conventional PT archive by a selection process for digital PT. Digital and conventional PT were performed in parallel for volunteer institutes, and the results were compared using feedback. To assess the quality of cytological assessment WSIs, 12 slides were collected and scanned using five different scanners, with four cytopathologists evaluating image quality through a questionnaire. Results: Among the 215 institutes, 108 and 107 participated in glass and digital PT, respectively. No significant difference was noted in category C (major discordance), although the number of discordant cases was slightly higher in the digital PT group. Leica, 3DHistech Pannoramic 250 Flash, and Hamamatsu NanoZoomer 360 systems showed comparable results in terms of image quality, feature presentation, and error rates for most cytological samples. Overall satisfaction was observed with the general convenience and image quality of digital PT. Conclusions As three-dimensional clusters are common and nuclear/chromatin features are critical for cytological interpretation, careful selection of scanners and optimal conditions are mandatory for the successful establishment of digital quality assurance programs in cytology.

Cancer organoids are three-dimensional mini-organ analogues derived from cancer tissues and have been proposed as models capable of simulating the structure and function of human organs and tissues in vitro. We sought to establish gastric cancer patient-derived organoids (PDOs) from tissues obtained by endoscopic biopsies. Gastric cancer-PDOs were successfully established and cultured from cancer tissues with gastric adenocarcinoma by endoscopic biopsies. To confirm that gastric cancer-PDOs were derived from cancer tissue, the consistency of the original cancer tissue was assessed by histopathological examination.As a result, it was confirmed that the shape and internal structure of gastric cancer-PDO were derived from the original gastric cancer cells, and the tumor specificity of gastric cancerPDO was confirmed through Periodic acid-Schiff (PAS) and polyclonal carcinoembryonic antigen antibody staining. These results demonstrate that gastric cancer-PDO models show the characteristics of primary tumors and have potential for drug screening and providing a personalized medicine platform.

Background: The Continuous Quality Improvement program for cytopathology in 2020 was completed during the coronavirus pandemic. In this study, we report the result of the quality improvement program. Methods: Data related to cytopathology practice from each institute were collected and processed at the web-based portal. The proficiency test was conducted using glass slides and whole-slide images (WSIs). Evaluation of the adequacy of gynecology (GYN) slides from each institution and submission of case glass slides and WSIs for the next quality improvement program were performed. Results: A total of 214 institutions participated in the annual cytopathology survey in 2020. The number of entire cytopathology specimens was 8,220,650, a reduction of 19.0% from the 10,111,755 specimens evaluated in 2019. Notably, the number of respiratory cytopathology specimens, including sputum and bronchial washing/ brushing significantly decreased by 86.9% from 2019, which could be attributed to the global pandemic of coronavirus disease. The ratio of cases with atypical squamous cells to squamous intraepithelial lesions was 4.10. All participating institutions passed the proficiency test and the evaluation of adequacy of GYN slides. Conclusions Through the Continuous Quality Improvement program, the effect of coronavirus disease 2019 pandemic, manifesting with a reduction in the number of cytologic examinations, especially in respiratory-related specimen has been identified. The Continuous Quality Improvement Program of the Korean Society for Cytopathology can serve as the gold standard to evaluate the current status of cytopathology practice in Korea.

Background/Aims: Hyaluronic acid (HA) regulates cell adhesion, migration and proliferation in various cancers. The clinical implications of HA in resected head and neck squamous cell carcinoma have not been elucidated. We investigated the clinical significance and prognostic value of the expression of tumoral and stromal HA and its related proteins in oropharyngeal and oral cavity cancer. Methods: Resected tissues from oropharyngeal or oral cavity cancer patients undergoing surgery were analysed in tissue microarrays divided into stroma and cancer panels. The expression levels of HA, HA synthases and hyaluronidases were also assessed by immunohistochemistry. Results: A total of 160 resected oropharyngeal or oral cavity cancer tissues were analysed. Stromal HA expression was observed more frequently in human papilloma virus (HPV)-negative tumors, but other clinicopathological characteristics did not differ. In patients with HPV-negative oral cavity cancers, high stromal HA expression was associated with significantly shorter recurrence-free survival and overall survival compared with low stromal HA expression. The expression of HA in both tumors and stroma was significantly correlated with poorer outcomes than other combinations in patients with HPV-negative oral cavity cancers. However, these prognostic roles of HA were not observed in patients with HPV-negative oropharyngeal cancers. In the HPV-stratified multivariate analysis, high stromal HA expression remained an independent indicator of poor prognosis in terms of recurrence-free survival. Conclusions High stromal HA and expression of HA in both tumors and stroma were correlated with poor prognosis in HPV-negative oral cavity cancer, but not in HPV-negative oropharyngeal cancers.

BACKGROUND: Progressive familial intrahepatic cholestasis (PFIC) is a heterogeneous group of autosomal recessive liver diseases that present as neonatal cholestasis. Little is known of this disease in Korea. METHODS: The records of five patients histologically diagnosed with PFIC, one with PFIC1 and four with PFIC2, by liver biopsy or transplant were reviewed, and ATP8B1 and ABCB11 mutation status was analyzed by direct DNA sequencing. Clinicopathological characteristics were correlated with genetic mutations. RESULTS: The first symptom in all patients was jaundice. Histologically, lobular cholestasis with bile plugs was the main finding in all patients, whereas diffuse or periportal cholestasis was identified only in patients with PFIC2. Giant cells and ballooning of hepatocytes were observed in three and three patients with PFIC2, respectively, but not in the patient with PFIC1. Immunostaining showed total loss of bile salt export pump in two patients with PFIC2 and focal loss in two. Lobular and portal based fibrosis were more advanced in PFIC2 than in PFIC1. ATP8B1 and ABCB11 mutations were identified in one PFIC1 and two PFIC2 patients, respectively. One PFIC1 and three PFIC2 patients underwent liver transplantation (LT). At age 7 months, one PFIC2 patient was diagnosed with concurrent hepatocellular carcinoma and infantile hemangioma in an explanted liver. The patient with PFIC1 developed steatohepatitis after LT. One patient showed recurrence of PFIC2 after 10 years and underwent LT. CONCLUSIONS: PFIC is not rare in patients with neonatal cholestasis of unknown origin. Proper clinicopathologic correlation and genetic testing can enable early detection and management.
Bile ; Biopsy ; Carcinoma, Hepatocellular ; Cholestasis ; Cholestasis, Intrahepatic ; Fatty Liver ; Fibrosis ; Genetic Testing ; Giant Cells ; Hemangioma ; Hepatocytes ; Humans ; Jaundice ; Korea ; Liver ; Liver Diseases ; Liver Transplantation ; Recurrence ; Sequence Analysis, DNA