Background: s/Aims: Reported incidence of extrahepatic bile duct cancer is higher in Asians than in Western populations. Korea, in particular, is one of the countries with the highest incidence rates of extrahepatic bile duct cancer in the world. Although research and innovative therapeutic modalities for extrahepatic bile duct cancer are emerging, clinical guidelines are currently unavailable in Korea. The Korean Society of Hepato-Biliary-Pancreatic Surgery in collaboration with related societies (Korean Pancreatic and Biliary Surgery Society, Korean Society of Abdominal Radiology, Korean Society of Medical Oncology, Korean Society of Radiation Oncology, Korean Society of Pathologists, and Korean Society of Nuclear Medicine) decided to establish clinical guideline for extrahepatic bile duct cancer in June 2021. Methods: Contents of the guidelines were developed through subgroup meetings for each key question and a preliminary draft was finalized through a Clinical Guidelines Committee workshop. Results: In November 2021, the finalized draft was presented for public scrutiny during a formal hearing. Conclusions The extrahepatic guideline committee believed that this guideline could be helpful in the treatment of patients.

Background/Aims: Based on their anatomy, cholangiocarcinomas (CCAs) are classified into intrahepatic, hilar, and distal CCAs. Although the diagnosis and treatment of each type of CCA are thought to be different, real-world data studies on the current practice are limited. Therefore, this study was designed to capture the current practice of diagnosing and treating perihilar CCA in Korea. Methods: We conducted a survey using an online platform. The questionnaire consisted of 18 questions designed to evaluate the current practice of diagnosing and treating perihilar CCA in Korea. The targets of this survey were biliary endoscopists who are members of the Korean Pancreatobiliary Association. Results: In total, 119 biliary endoscopists completed the survey. Of the respondents, 89.9% thought that the use of the International Classification of Diseases, 11th Revision (ICD-11) system is necessary to classify CCA. Approximately half of the respondents would recommend surgery or chemotherapy until patients were 80 years of age. For the pathological diagnosis of CCA, endoscopic retrograde cholangiopancreatography with biopsy was the most preferred modality. Routine preoperative biliary drainage was performed by 44.5% of the respondents. For operable CCAs, 64.7% of the respondents preferred endoscopic biliary drainage using plastic stents. For palliative biliary drainage, 69.7% of the respondents used plastic stents. For palliative endoscopic biliary drainage using metal stents, 63% of the respondents preferred the stent-in-stent method. Conclusions A new coding system using the ICD-11 is needed for classifying CCAs. Guidelines for diagnosing and treating CCA based on the clinical situation in Korea are needed.

Background: This study aimed to evaluate the relationship between clinical experience and death certificate (DC) errors by analyzing DCs written by experienced emergency physicians (EPs). Methods: DCs issued by four experienced EPs over a 10-year period were retrospectively reviewed. DC errors were divided into major and minor errors based on whether they affected the cause of death (COD) determination. The errors were judged through first and second evaluations. Basic information regarding DCs and 10-year changes in DC errors were analyzed. Results: A total of 505 DCs were analyzed, with an average of 34 to 70 for each study year.The number of CODs written in the DCs tended to decrease over time. The presentation of major DC errors did not show a tendency to change over time. However, the sum of the major and minor errors tended to increase over time. Secondary conditions as the underlying COD tended to increase, and the incompatible causal relationships between CODs tended to decrease over time in the detailed analysis of major errors. The increasing tendency for incorrect other significant conditions, incorrect type of accident, incorrect intention of the external cause, no record of the trauma mechanism, and record of the trauma mechanism without another COD were found in the detailed analysis of minor errors. Conclusion DC errors did not decrease as clinical experience increased. Education to reduce DC errors and a feedback process for written DCs are necessary, regardless of clinical experience.

In this study, the Ti6Al4V specimens were fabricated using selective laser melting (SLM) method (Ti6Al4V-AS group). These specimens were performed to heat treatment at 950℃ and 550℃ using vacuum electric furnace (Ti6Al4V-HT group). The mechanical properties, metallographic shape, crystalline structure, and chemical compositions of the alloy specimens before and after heat treatment were analyzed. The Ti6Al4V-AS group showed ultimate tensile strength (UTS) and low elongation values. Acicular crystal grains were observed in metallographic image and the α'-Ti phase was dominant. After heat treatment (Ti6Al4V-HT group), the UTS was lowered and the elongation was increased. In addition, a lamellar structure in which columnar crystal grains are arranged was observed, α+β-Ti phase was formed, and crystallinity increased. As a result of analyzing the chemical composition, the Ti6Al4V-AS specimen contained a higher carbon content than the Ti6Al4V-HT specimen. This high carbon content could be related to the formation of α'-phase, high strength and low elongation of the Ti6Al4V-AS specimen. Ti6Al4V-HT specimen showed that the overall carbon content was low, but the carbon content was locally high in the α-Ti phase region. Therefore, it is necessary to control effectively the incorporation of carbon gas in the production of Ti6Al4V specimens using SLM.

Background: This study was undertaken to compare the sensitivities of mice strains during tumor induction by transcription activator-like effector nucleases (TALEN)-mediated Trp53 mutant gene. Alterations of their tumorigenic phenotypes including survival rate, tumor formation and tumor spectrum, were assessed in FVB/N-Trp53 em2Hwl /Korl and C57BL/6-Trp53 em1Hwl /Korl knockout (KO) mice over 16 weeks. Results: Most of the physiological phenotypes factors were observed to be higher in FVB/N-Trp53 em2Hwl /Korl KO mice than C57BL/6-Trp53 em1Hwl /Korl KO mice, although there were significant differences in the body weight, immune organ weight, number of red blood cells, mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), mean corpuscular hemoglobin concentration (MCHC), platelet count (PLT), total bilirubin (Bil-T) and glucose (Glu) levels in the KO mice relative to the wild type (WT) mice. Furthermore, numerous solid tumors were also observed in various regions of the surface skin of FVB/N-Trp53 em2Hwl /Korl KO mice, but were not detected in C57BL/6-Trp53 em1Hwl /Korl KO mice. The most frequently observed tumor in both the Trp53 KO mice was malignant lymphoma, while soft tissue teratomas and hemangiosarcomas were only detected in the FVB/N-Trp53 em2Hwl /Korl KO mice. Conclusions Our results indicate that the spectrum and incidence of tumors induced by the TALEN-mediated Trp53 mutant gene is greater in FVB/N-Trp53 em2Hwl /Korl KO mice than C57BL/6-Trp53 em1Hwl /Korl KO mice over 16 weeks.

Background: In response to the disaster of coronavirus disease 2019 (COVID-19) pandemic, Seoul Metropolitan Government (SMG) established a patient facility for mild condition patients other than hospital. This study was conducted to investigate the operation and necessary resources of a community treatment center (CTC) operated in Seoul, a metropolitan city with a population of 10 million. Methods: To respond COVID-19 epidemic, the SMG designated 5 municipal hospitals as dedicated COVID-19 hospitals and implemented one CTC cooperated with the Boramae Municipal Hospital for COVID-19 patients in Seoul. As a retrospective cross-sectional observational study, retrospective medical records review was conducted for patients admitted to the Seoul CTC. The admission and discharge route of CTC patients were investigated. The patient characteristics were compared according to route of discharge whether the patient was discharged to home or transferred to hospital. To report the operation of CTC, the daily mean number of tests (reverse transcription polymerase chain reaction and chest X-ray) and consultations by medical staffs were calculated per week. The list of frequent used medications and who used medication most frequently were investigated. Results: Until May 27 when the Seoul CTC was closed, 26.5% (n = 213) of total 803 COVID-19 patients in Seoul were admitted to the CTC. It was 35.7% (n = 213) of 597 newly diagnosed patients in Seoul during the 11 weeks of operation. The median length of stay was 21 days (interquartile range, 12–29 days). A total of 191 patients (89.7%) were discharged to home after virologic remission and 22 (10.3%) were transferred to hospital for further treatment.Fifty percent of transferred patients were within a week since CTC admission. Daily 2.5–3.6consultations by doctors or nurses and 0.4–0.9 tests were provided to one patient. The most frequently prescribed medication was symptomatic medication for COVID-19 (cough/ sputum and rhinorrhea). The next ranking was psychiatric medication for sleep problem and depression/anxiety, which was prescribed more than digestive drug. Conclusion In the time of an infectious disease disaster, a metropolitan city can operate a temporary patient facility such as CTC to make a surge capacity and appropriately allocate scarce medical resource.

To evaluate the carcinogenicity of p27 knockout (KO) mice with RNA-guided endonuclease (RGENs)-mediated p27 mutant exon I gene (IΔ), alterations in the carcinogenic phenotypes including tumor spectrum, tumor suppressor proteins, apoptotic proteins and cell cycle regulators were observed in p27 (IΔ) KO mice after treatment with 7,12-Dimethylbenz[a]anthracene (DMBA) and 12-O-tetradecanoylphorbol-13-acetate (TPA)(DT) for 5 months. The target region (544~571 nt) in exon I of the p27 gene was successfully disrupted in p27 (IΔ) KO mice using the RGEN-induced non-homologous end joining (NHEJ) technique. After DT exposure for 5 months, a few solid tumors (identified as squamous cell carcinoma) developed on the surface of back skin of DT-treated p27 (IΔ) KO mice. Also, squamous cell hyperplasia with chronic inflammation was detected in the skin dermis of DT-treated p27 (IΔ) KO mice, while the Vehicle+p27 (IΔ) KO mice and WT mice maintained their normal histological skin structure. A significant increase was observed in the expression levels of tumor suppressor protein (p53), apoptotic proteins (Bax, Bcl-2 and Caspase-3) and cell-cycle regulator proteins (Cyclin D1, CDK2 and CDK4) in the skin of DT-treated p27 (IΔ) KO mice, although their enhancement ratio was varied. Taken together, the results of the present study suggest that squamous cell carcinoma and hyperplasia of skin tissue can be successfully developed in new p27 (IΔ) KO mice produced by RGEN-induced NHEJ technique following DT exposure for 5 months.
9,10-Dimethyl-1,2-benzanthracene* ; Animals ; Carcinogenesis ; Carcinoma, Squamous Cell* ; Cell Cycle ; Dermis ; Epithelial Cells* ; Exons ; Hyperplasia* ; Inflammation ; Mice* ; Phenotype ; Skin ; Tumor Suppressor Proteins

The present study reports our experience of treating four cases of symptomatic discoid medial meniscus, three of which were bilateral. We performed partial meniscectomy with a four-portal technique using a knife leaving a 6 mm peripheral margin after confirmation of magnetic resonance imaging findings. Clinical results were assessed at the end of 2-year follow-up using the Knee Injury and Osteoarthritis Outcome Score and a visual analogue scale. We obtained satisfactory clinical results without recurrence of the symptoms in all cases.
Follow-Up Studies ; Knee ; Knee Injuries ; Magnetic Resonance Imaging ; Menisci, Tibial ; Osteoarthritis ; Recurrence ; Tears

Pigmented villonodular synovitis (PVNS) is a rare, benign, soft tissue neoplasm affecting the synovium of joints, classified as localized and diffused type. Localized type is more common, arising from synovium of joints, bursae, and tendon sheaths. Diffused type is relatively rare, frequently arising from an extra-articular lesion, and sometimes from an intramuscular or subcutaneous lesion. Although the cause of occurrence is not yet clear, recently it has been known as a benign neoplasm rather than an inflammatory or reactive process. We performed a total excision of the PVNS in a pretibial lesion and achieved a good result. We report on the case with a review of the literature.
Giant Cell Tumors* ; Giant Cells* ; Joints ; Soft Tissue Neoplasms ; Synovial Membrane ; Synovitis, Pigmented Villonodular ; Tendons ; Tenosynovitis* ; Tibia

The role of neoadjuvant chemoradiation therapy in locally advanced pancreatic cancer (LAPC) is still controversial. The aim of this study was to evaluate surgical downstaging after concurrent chemoradiation therapy (CCRT) for LAPC by measuring the objective changes after treatment. From January 2003 through July 2011, 54 patients with LAPC underwent neoadjuvant CCRT. Computed tomography findings of the tumor size, including major vessel invasion, were analyzed before and after CCRT. Among the total recruited patients, 14 had borderline resectable malignancy and another 40 were unresectable before CCRT. After CCRT, a partial response was achieved in four patients. Stable disease and further disease progression were achieved in 36 and 14 patients, respectively. Tumor size showed no significant difference before and after CCRT (3.6 +/- 1.1 vs. 3.6 +/- 1.0 cm, P = 0.61). Vessel invasion showed improvement in two patients, while 13 other patients showed further tumor progression. Thirty-nine patients with unresectable malignancy and 11 patients with borderline resectable malignancy at time of initial diagnosis remained unchanged after CCRT. Four patients with borderline pancreatic malignancy progressed to an unresectable stage, whereas one unresectable pancreatic malignancy improved to a borderline resectable stage. Only one patient with borderline resectable disease underwent operation after CCRT; however, curative resection failed due to celiac artery invasion and peritoneal seeding. The adverse events associated with CCRT were tolerable. In conclusion, preoperative CCRT in LAPC rarely leads to surgical downstaging, and it could lower resectability rates.
Adenocarcinoma/radiography/therapy ; Adult ; Aged ; Aged, 80 and over ; Antimetabolites, Antineoplastic/therapeutic use ; Antineoplastic Combined Chemotherapy Protocols/therapeutic use ; Capecitabine/therapeutic use ; Carcinoma, Pancreatic Ductal/*radiography/*therapy ; Chemoradiotherapy/adverse effects/*methods ; Combined Modality Therapy ; Deoxycytidine/analogs & derivatives/therapeutic use ; Disease Progression ; Female ; Fluorouracil/therapeutic use ; Humans ; Male ; Middle Aged ; Neoadjuvant Therapy ; Neoplasm Staging ; Pancreas/blood supply/pathology ; Pancreatic Neoplasms/*radiography/*therapy ; Retrospective Studies ; Treatment Outcome