Osteosarcoma is the most frequent primary malignant bone tumor with higher incidences in children and adolescents. Despite clinical evolutions, patients with osteosacoma have had a poor prognosis. There has been increasing evidence that cancer is a stem cell disease. This study sought to isolate and characterize cancer stem cells from human osteosarcoma with relevant literature reviews. Here we show that the emerging evidence suggests osteosarcoma should be regarded as a differentiation disease such as stem cell disease. Two human osteosarcoma cell lines were cultured in non-adherent culture conditions as sarcospheres. Sarcospheres were observed using histomorphology and alkaline phosphatase (ALP) staining. Expression of the embryonic stem cell marker was analyzed with use of reverse transcriptase-PCR. Sarcospheres could be reproduced consistently throughout multiple passages and produced adherent osteosarcoma cell cultures. Expression of stem cell-associated genes such as those encoding Nanog, octamer-binding transcription factor 3/4, sex determining region Y box 2 , c-Myc and ALP indicated pluripotent stem-like cells. These results support the extension of the cancer stem cell theory to include osteosarcoma. Understanding the cancer stem cell derived from human osteosarcoma could lead to the evolution of diagnosis and treatment for osteosarcoma patients.

Incidental thyroid nodules are commonly detected on ultrasonography (US). This has contributed to the rapidly rising incidence of low-risk papillary thyroid carcinoma over the last 20 years. The appropriate diagnosis and management of these patients is based on the risk factors related to the patients as well as the thyroid nodules. The Korean Society of Thyroid Radiology (KSThR) published consensus recommendations for US-based management of thyroid nodules in 2011 and revised them in 2016. These guidelines have been used as the standard guidelines in Korea. However, recent advances in the diagnosis and management of thyroid nodules have necessitated the revision of the original recommendations. The task force of the KSThR has revised the Korean Thyroid Imaging Reporting and Data System and recommendations for US lexicon, biopsy criteria, US criteria of extrathyroidal extension, optimal thyroid computed tomography protocol, and US follow-up of thyroid nodules before and after biopsy. The biopsy criteria were revised to reduce unnecessary biopsies for benign nodules while maintaining an appropriate sensitivity for the detection of malignant tumors in small (1–2 cm) thyroid nodules. The goal of these recommendations is to provide the optimal scientific evidence and expert opinion consensus regarding US-based diagnosis and management of thyroid nodules.

Because of repeated failures of clinical trials, the concept of Alzheimer's disease (AD) has been changing rapidly in recent years. As suggested by the National Institute on Aging and the Alzheimer's Association Research Framework, the diagnosis and classification of AD is now based on biomarkers rather than on symptoms, allowing more accurate identification of proper candidates for clinical trials by pathogenesis and disease stage. Recent development in neuroimaging has provided a way to reveal the complex dynamics of amyloid and tau in the brain in vivo, and studies of blood biomarkers are taking another leap forward in diagnosis and treatment of AD. In the field of basic and translational research, the development of animal models and a deeper understanding of the role of neuroinflammation are taking a step closer to clarifying the pathogenesis of AD. Development of big data and the Internet of Things is also incorporating dementia care and research into other aspects. Largescale genetic research has identified genetic abnormalities that can provide a foundation for precision medicine along with the aforementioned digital technologies. Through the first international conference of the Korean Dementia Association, experts from all over the world gathered to exchange opinions with association members on these topics. The Academic Committee of the Korean Dementia Association briefly summarizes the contents of the lectures to convey the depth of the conference and discussions. This will be an important milestone in understanding the latest trends in AD's pathogenesis, diagnostic and therapeutic research and in establishing a future direction.

PURPOSE: Melanoma is a highly heterogeneous neoplasm, composed of subpopulations of tumor cells with distinct molecular and biological phenotypes and genotypes. In this study, to determine the genetic heterogeneity between primary and metastatic melanoma in Korean melanoma patients, we evaluated several well-known genetic alterations of melanoma. In addition, to elucidate the clinical relevance of each genetic alteration and heterogeneity between primary and metastatic lesions, clinical features and patient outcome were collected. MATERIALS AND METHODS: In addition to clinical data, BRAF, NRAS, GNAQ/11 mutation and KIT amplification data was acquired from an archived primary Korean melanoma cohort (KMC) of 188 patients. Among these patients, 43 patients were included for investigation of tumor heterogeneity between primary melanoma and its corresponding metastatic lesions. RESULTS: Overall incidence of genetic aberrations of the primary melanomas in KMC was 17.6% of BRAF V600, 12.6% of NRAS mutation, and 28.6% of KIT amplification. GNAQ/11 mutation was seen in 66.6% of the uveal melanoma patients. Patients with BRAF mutation were associated with advanced stage and correlated to poor prognosis (p < 0.01). Among 43 patients, 55.8% showed heterogeneity between primary and metastatic lesion. The frequency of BRAF mutation and KIT amplification significantly increased in the metastatic lesions compared to primary melanomas. GNAQ/11 mutation showed 100% homogeneity in uveal melanoma patients. CONCLUSION: Our data demonstrated heterogeneity between primary melanomas and corresponding metastatic lesions for BRAF, NRAS mutation and KIT amplification. However, GNAQ/11 mutation was genetically homogeneous between primary and metastatic melanoma lesions in uveal melanoma.
Cohort Studies ; Genetic Heterogeneity ; Genotype ; Humans ; Incidence ; Melanoma* ; Phenotype ; Population Characteristics* ; Prognosis

Yonsei Dermatology celebrated its centennial in 2017, marking 100 years since Kung Sun Oh established the first Department of Dermatology and Urology in Korea in 1917. Following the footsteps of Kung Sun Oh, a pioneer of Korean dermatology, its members united and worked to provide the best medical service and achieve academic milestones in dermatology. Over the past hundred years, Yonsei Dermatology has played a pivotal role in the advancement of medical science and academia in Korea. The main activities of the department include medical care, education, and dermatologic research. Its research activities have encompassed a wide spectrum of dermatologic manifestations from skin immunology and pathology to introduction of newly developed treatment technologies. As Kung Sun Oh was the first Korean professor of dermatology at Severance Medical School and a passionate educator, we continue to serve his will by nurturing medical students and dermatology specialists to serve as global medical leaders. The Kung Sun Oh Memorial Lecture, first hosted in 1977, was the beginning of mutual international academic exchange in the field of dermatology in Korea. The memorial lecture has played a major role in advancing the academic status of Korean dermatological science by inviting distinguished dermatologists from around the world as guest lecturers. Yonsei Dermatology has played a key role in the history of modern medicine and dermatology in Korea over the last 100 years and continues to make an impact.
Allergy and Immunology ; Dermatology* ; Education ; History, Modern 1601- ; Humans ; Korea* ; Pathology ; Schools, Medical ; Skin ; Solar System ; Specialization ; Students, Medical ; Urology

This paper reports a rare case of the symptomatic third metatarsal (MT3) - lateral cuneiform (LC) in a 55-year-old male who presented with complaints of severe intermittent pain in his right foot. Plain radiographs and computed tomography scans revealed sclerosis and irregularity at this joint. The intraoperative findings demonstrated a fibrocartilaginous coalition. The pain had improved one year after removing the MT3-LC joint by en bloc and arthrodesis.
Arthrodesis ; Foot ; Humans ; Joints* ; Male ; Metatarsal Bones ; Middle Aged ; Sclerosis

BACKGROUND: At most centers, general anesthesia (GA) has been preferred for endovascular treatment (EVT) of ruptured intracranial aneurysms (RIAs). In this study, we analyzed procedural results, clinical outcomes, and follow-up angiographic findings for patients undergoing EVT for RIA under local anesthesia (LA) with conscious sedation (CS). METHODS: We retrospectively evaluated 308 consecutive patients who underwent EVT for RIAs at a single institution between June 2009 and February 2017. EVT under LA with CS was considered for all patients with aneurysmal subarachnoid hemorrhage, regardless of Hunt and Hess (HH) scale score. RESULTS: EVT was performed for 320 aneurysms in 308 patients with subarachnoid hemorrhages. The mean patient age was 55.5±12.6 years. Moderate (III) and poor (IV, V) HH grades were observed in 75 (24.4%) and 77 patients (25%), respectively. Complete occlusion immediately after EVT was achieved for 270 (84.4%) of 320 aneurysms. Thromboembolic complications and intraprocedural ruptures occurred in 25 (7.8%) and 14 cases (4.3%), respectively. The morbidity rate at discharge (as defined by a modified Rankin scale score of 3 or greater) was 27.3% (84/308), while the mortality rate was 11.7% (36/308). Follow-up angiographic results were available for 210 (68.1%) of 308 patients. Recanalization was observed in 64 (29.3%) of 218 aneurysms in 210 patients. CONCLUSION: Based on our experience, EVT for RIAs under LA with CS was feasible, regardless of the clinical grade of the subarachnoid hemorrhage. Complication rates and follow-up angiographic results were also comparable to those observed when GA was used to perform the procedure.
Anesthesia, General ; Anesthesia, Local ; Aneurysm ; Conscious Sedation ; Endovascular Procedures ; Follow-Up Studies ; Humans ; Intracranial Aneurysm ; Mortality ; Retrospective Studies ; Rupture ; Subarachnoid Hemorrhage

Korean Society of Thyroid-Head and Neck Surgery appointed a Task Force to develop clinical practice guidelines for the surgical treatment of laryngeal cancer. This Task Force conducted a systematic search of the EMBASE, MEDLINE, Cochrane Library, and KoreaMed databases to identify relevant articles, using search terms selected according to the key questions. Evidence-based recommendations were then created on the basis of these articles. An external expert review and Delphi questionnaire were applied to reach consensus regarding the recommendations. The resulting guidelines focus on the surgical treatment of laryngeal cancer with the assumption that surgery is the selected treatment modality after a multidisciplinary discussion in any context. These guidelines do not, therefore, address non-surgical treatment such as radiation therapy or chemotherapy. The committee developed 62 evidence-based recommendations in 32 categories intended to assist clinicians during management of patients with laryngeal cancer and patients with laryngeal cancer, and counselors and health policy-makers.
Advisory Committees ; Consensus ; Counseling ; Drug Therapy ; Glottis ; Humans ; Laryngeal Neoplasms* ; Neck*

PURPOSE: Elevated serum concentration of fibrinogen and decreased serum concentration of albumin have been reported to be markers of elevated systemic inflammation. We attempted to investigate the prognostic influence of preoperative fibrinogen to albumin ratio (FAR) for breast cancer. METHODS: Data from 793 consecutive primary breast cancer patients were retrospectively analyzed. Serum levels of fibrinogen and albumin were tested before curative surgery. Subjects were grouped into two groups according to the cutoff value determined by performing the receiver operating characteristic curve analysis: the high FAR group (FAR>7.1) and the low FAR group (FAR≤7.1). Overall survival was assessed using the Kaplan-Meier estimator. Independent prognostic significance was analyzed using the Cox proportional hazards model. RESULTS: The high FAR group had a worse prognosis compared to the low FAR group (log-rank test, p<0.001). The prognostic effect of FAR was more significant than that of single markers such as fibrinogen (log-rank test, p=0.001) or albumin (log-rank test, p=0.001). The prognostic effect of FAR was prominent in the stage II/III subgroup (log-rank test, p<0.001) and luminal A-like subtype (log-rank test, p<0.001). FAR was identified as a significant independent factor on both univariate (hazard ratio [HR], 2.722; 95% confidence interval [CI], 1.659–4.468; p<0.001) and multivariate analysis (HR, 2.622; 95% CI, 1.455–4.724; p=0.001). CONCLUSION: Preoperative FAR was a strong independent prognostic factor in breast cancer. Its prognostic effect was more prominent in the stage II/III subgroup and in the luminal A-like subtype. Therefore, preoperative FAR can be utilized as a useful prognosticator for breast cancer patients. Further studies are needed to validate its applications in clinical settings.
Breast Neoplasms* ; Breast* ; Fibrinogen* ; Humans ; Inflammation ; Multivariate Analysis ; Phenobarbital ; Prognosis ; Proportional Hazards Models ; Retrospective Studies ; ROC Curve ; Serum Albumin ; Survival Analysis

PURPOSE: Despite recommendations for introducing student internships (SI) in undergraduate medical education in Korea, the feasibility of surgical SIs has not been demonstrated in the Korean context. We thus identified tasks that could be performed by surgical student interns in a Korean education hospital. METHODS: The opinions of surgery clerkship directors of medical schools nationwide, regarding the tasks, symptoms and signs, disease entities, and procedures that student interns could perform in their hospitals, were subjected to descriptive analysis. RESULTS: Out of the 41 medical schools in Korea, 32 responded. Five implemented an optimal-quality SI program. Two schools considered third-year clerkship as SI. The respondents replied that student interns could be involved in basic nonspecific tasks such as history taking, physical examination, medial recording, reporting patients' status, and assisting during surgery. However, more surgery-specific tasks such as perioperative management or caring for a patient with acute abdominal pain were considered difficult for student interns to encounter in the Korean context. CONCLUSION: Surgical educators should determine a specific role for student interns and encourage them to perform surgery-specific tasks. We recommend societal and system support, and curriculum renovation to establish an SI program in Korea.
Abdominal Pain ; Clinical Clerkship ; Clinical Competence ; Curriculum ; Surveys and Questionnaires ; Education ; Education, Medical, Undergraduate ; Humans ; Internship and Residency* ; Korea ; Physical Examination ; Schools, Medical