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: Endoscopic ultrasound-guided fine-needle aspiration/biopsy (EUS-FNA/B) is essential in diagnosing solid pancreatic lesions (SPLs), but without rapid on-site evaluation (ROSE), a repeat EUS-FNA/B is crucial for clarifying an inconclusive diagnosis. We aimed to evaluate factors associated with improved diagnostic performance of repeat EUS-FNA/B for initially inconclusive SPL diagnoses without ROSE. Methods: Of 5,894 patients subjected to EUS-FNA/B, 237 (4.0%) with an initially inconclusive diagnosis of SPLs were retrospectively enrolled from five tertiary medical centers between January 2016 and June 2021. Diagnostic performance and procedural factors of EUS-FNA/B were analyzed. Results: The diagnostic accuracies of first and repeat EUS-FNA/B were 96.2% and 67.6%, respectively. Of 237 patients with an inconclusive diagnosis from initial EUS-FNA/B, 150were pathologically diagnosed after repeat EUS-FNA/B. In multivariate analysis of repeat EUS-FNA/B, tumor location (body/tail vs head: odds ratio [OR], 3.74; 95% confidence inter-val [CI], 1.48 to 9.46), number of needle passes (≥4 vs ≤3: OR, 4.80; 95% CI, 1.44 to 15.99),needle type (FNB vs FNA: OR, 3.26; 95% CI, 1.44 to 7.36), needle size (22 gauge vs 19/20 gauge: OR, 2.35; 95% CI, 1.19 to 4.62), and suction method (suction vs others: OR, 5.19;95% CI, 1.30 to 20.75) were associated with a significantly improved diagnostic performance. Conclusions Repeat EUS-FNA/B is essential for patients with an inconclusive EUS-FNA/B without ROSE. To improve the diagnostic performance of repeated EUS-FNA/B, it is recom-mended that 22-gauge FNB needles, ≥4 needle passes, and suction methods are used.

Purpose: The value of the genomic profiling by targeted gene-sequencing on radiation therapy response prediction was evaluated through integrated analysis including clinical information. Radiation response prediction model was constructed based on the analyzed findings. Materials and Methods: Patients who had the tumor sequenced using institutional cancer panel after informed consent and received radiotherapy for the measurable disease served as the target cohort. Patients with irradiated tumor locally controlled for more than 6 months after radiotherapy were defined as the durable local control (DLC) group, otherwise, non-durable local control (NDLC) group. Significant genomic factors and domain knowledge were used to develop the Bayesian Network model to predict radiotherapy response. Results: Altogether, 88 patients were collected for analysis. Of those, 41 (43.6%) and 47 (54.4%) patients were classified as the NDLC and DLC group, respectively. Somatic mutations of NOTCH2 and BCL were enriched in the NDLC group, whereas, mutations of CHEK2, MSH2, and NOTCH1 were more frequently found in the DLC group. Altered DNA repair pathway was associated with better local failure–free survival (hazard ratio, 0.40; 95% confidence interval, 0.19 to 0.86; p=0.014). Smoking somatic signature was found more frequently in the DLC group. Area under the receiver operating characteristic curve of the Bayesian network model predicting probability of 6-month local control was 0.83. Conclusion Durable radiation response was associated with alterations of DNA repair pathway and smoking somatic signature. Bayesian network model could provide helpful insights for high precision radiotherapy. However, these findings should be verified in prospective cohort for further individualization.

Background: Human breast milk is essential and provides irreplaceable nutrients for early humans. However, breastfeeding is not easy for various reasons in medical institution environments. Therefore, in order to improve the breastfeeding environment, we investigated the difficult reality of breastfeeding through questionnaire responses from medical institution workers. Methods: A survey was conducted among 179 medical institution workers with experience in childbirth within the last five years. The survey results of 175 people were analyzed, with incoherent answers excluded. Results: Of the 175 people surveyed, a total of 108 people (61.7%) worked during the day, and 33 people (18.9%) worked in three shifts. Among 133 mothers who stayed with their babies in the same nursing room, 111 (93.3%) kept breastfeeding for more than a month, but among those who stayed apart, only 10 (71.4%) continued breastfeeding for more than a month (P = 0.024). Ninety-five (88.0%) of daytime workers, 32 (94.1%) two-shift workers, and 33 (100%) three-shift workers continued breastfeeding for more than a month (P = 0.026). Workers in general hospitals tended to breastfeed for significantly longer than those that worked in tertiary hospitals (P = 0.003). A difference was also noted between occupation categories (P = 0.019), but a more significant difference was found in the comparison between nurses and doctors (P = 0.012). Longer breastfeeding periods were noted when mothers worked three shifts (P = 0.037). Depending on the period planned for breastfeeding prior to childbirth, the actual breastfeeding maintenance period after birth showed a significant difference (P = 0.002). Of 112 mothers who responded to the question regarding difficulties in breastfeeding after returning to work, 87 (77.7%) mentioned a lack of time caused by being busy at work, 82 (73.2%) mentioned the need for places and appropriate circumstances. Conclusion In medical institutions, it is recommended that environmental improvements in medical institutions, the implementation of supporting policies, and the provision of specialized education on breastfeeding are necessary to promote breastfeeding.

This study summarizes the recent cutting-edge approaches for dentin regeneration that still do not offer adequate solutions. Tertiary dentin is formed when odontoblasts are directly affected by various stimuli. Recent preclinical studies have reported that stimulation of the Wnt/β-catenin signaling pathway could facilitate the formation of reparative dentin and thereby aid in the structural and functional development of the tertiary dentin. A range of signaling pathways, including the Wnt/β-catenin pathway, is activated when dental tissues are damaged and the pulp is exposed. The application of small molecules for dentin regeneration has been suggested as a drug repositioning approach. This study reviews the role of Wnt signaling in tooth formation, particularly dentin formation and dentin regeneration. In addition, the application of the drug repositioning strategy to facilitate the development of new drugs for dentin regeneration has been discussed in this study.

This study summarizes the recent cutting-edge approaches for dentin regeneration that still do not offer adequate solutions. Tertiary dentin is formed when odontoblasts are directly affected by various stimuli. Recent preclinical studies have reported that stimulation of the Wnt/β-catenin signaling pathway could facilitate the formation of reparative dentin and thereby aid in the structural and functional development of the tertiary dentin. A range of signaling pathways, including the Wnt/β-catenin pathway, is activated when dental tissues are damaged and the pulp is exposed. The application of small molecules for dentin regeneration has been suggested as a drug repositioning approach. This study reviews the role of Wnt signaling in tooth formation, particularly dentin formation and dentin regeneration. In addition, the application of the drug repositioning strategy to facilitate the development of new drugs for dentin regeneration has been discussed in this study.

Purpose: Intraoperative frozen section biopsy is used to reduce the margin positive rate and re-excision rate and has been reported to have high diagnostic accuracy. A majority of breast surgeons in the Republic of Korea routinely perform frozen section biopsy to assess margins intraoperatively, despite its long turnaround time and high resource requirements. This study aims to determine whether omitting frozen section biopsy for intraoperative margin evaluation in selected patients is non-inferior to performing frozen section biopsy in terms of resection margin positivity rate. Methods This study is a phase III, randomized controlled, parallel-group, multicenter non-inferiority clinical trial. Patients meeting the inclusion criteria and providing written informed consent will be randomized to the “frozen section biopsy” or “frozen section biopsy omission” group after lumpectomy. Patients with clinical stage T1–T3 disease who are diagnosed with invasive breast cancer by core-needle biopsy and plan to undergo breast-conserving surgery will be included in this study. If a daughter nodule, non-mass enhancement, or microcalcification is identified on preoperative imaging, these features must be within 1 cm of the main mass for inclusion in the trial. The target sample size is 646 patients per arm. The primary endpoint will be the resection margin positive rate, and the secondary endpoints include the reoperation rate, operating time, residual cancer after reoperation, residual cancer after re-excision according to the frozen section biopsy result, resection volume, patient quality of life, and cost-effectiveness.Discussion: This is the first randomized clinical trial utilizing frozen section biopsy for intraoperative margin evaluation and aims to determine the non-inferiority of omitting frozen section biopsy in selected patients compared to performing frozen section biopsy.We expect that this trial will help surgeons perform the procedure more efficiently while ensuring patient safety.

Purpose: The positions of the mandibular foramen (MnF) and the lingula affect the success rate of inferior alveolar nerve block. The objective of this study was to investigate aspects of the MnF and the lingula relevant for mandibular block anesthesia using cone-beam computed tomography (CBCT). Materials and Methods: Fifty CBCT scans were collected from a picture archiving and communications system. All scans were taken using an Alphard Vega 3030 (Asahi Roentgen Co. Ltd., Kyoto, Japan). Fifty-eight MnFs of 30 subjects were included in the study. The position of the MnF, the size of the MnF, the position of the lingula, the size of the lingula, and the shape of the lingula were measured and recorded. All data were statistically analyzed at a significance level of p<0.05. Results: The position of MnF was 0.1 mm and 0.8 mm below the occlusal plane in males and females, respectively. The horizontal position of the MnF was slightly anterior to the center of the ramus in males and in the center in females (p<0.05). The vertical position of the MnF was lower in females than in males (p<0.05). The MnF was an oval shape with a longer anteroposterior dimension. The height of the lingula was 9.3 mm in males and 8.2 mm in females. The nodular type was the most common shape of the lingula, followed by the triangular, truncated, and assimilated types. Conclusion CBCT provided useful information about the MnF and lingula. This information could improve the success rate of mandibular blocks.

Background: A national immunization program (NIP) to prevent disease and reduce mortality from vaccine preventable diseases (VPD) is very important. Methods: We analyzed only the anaphylaxis cases that occurred between 2001 and 2016 that Korea Centers for Disease Control and Prevention (KCDC) determined had a definite causal relationship with a vaccine. The clinical symptoms were assessed according to the Brighton Collaboration case definition (BCCD) level. Results: During the period, there were 13 cases of vaccine-related anaphylaxis. The median age was 9 years (range, 1 month to 59 years). The incidence of anaphylaxis per million doses was 0.090 in 2005, 0.079 in 2012, 0.071 in 2013, 0.188 in 2015, and 0.036 in 2016. Of those cases, 23.1% were influenza vaccines, and 76.9% were BCCD level 2. Epinephrine was used in 46.2%. Conclusion Vaccine-related anaphylaxis seems to have been very rare in the past, but health care professionals must always be aware of anaphylaxis.

BACKGROUND: There has been no practical guidelines for the management of patients with central nervous system (CNS) tumors in Korea for many years. Thus, the Korean Society for Neuro-Oncology (KSNO), a multidisciplinary academic society, started to prepare guidelines for CNS tumors from February 2018. METHODS: The Working Group was composed of 35 multidisciplinary medical experts in Korea. References were identified through searches of PubMed, MEDLINE, EMBASE, and Cochrane CENTRAL using specific and sensitive keywords as well as combinations of keywords. RESULTS: First, the maximal safe resection if feasible is recommended. After the diagnosis of a glioblastoma with neurosurgical intervention, patients aged ≤70 years with good performance should be treated by concurrent chemoradiotherapy with temozolomide followed by adjuvant temozolomide chemotherapy (Stupp's protocol) or standard brain radiotherapy alone. However, those with poor performance should be treated by hypofractionated brain radiotherapy (preferred)±concurrent or adjuvant temozolomide, temozolomide alone (Level III), or supportive treatment. Alternatively, patients aged >70 years with good performance should be treated by hypofractionated brain radiotherapy+concurrent and adjuvant temozolomide or Stupp's protocol or hypofractionated brain radiotherapy alone, while those with poor performance should be treated by hypofractionated brain radiotherapy alone or temozolomide chemotherapy if the patient has methylated MGMT gene promoter (Level III), or supportive treatment. CONCLUSION: The KSNO's guideline recommends that glioblastomas should be treated by maximal safe resection, if feasible, followed by radiotherapy and/or chemotherapy according to the individual comprehensive condition of the patient.
Brain ; Central Nervous System ; Chemoradiotherapy ; Diagnosis ; Drug Therapy ; Glioblastoma ; Humans ; Korea ; Radiotherapy