Background/Aims: Inaccurate prediction of lymph node metastasis (LNM) may lead to unnecessary surgery following endoscopic resection of T1 colorectal cancer (CRC). We aimed to validate the usefulness of artificial intelligence (AI) models for predicting LNM in patients with T1 CRC. Methods: We analyzed the clinical data, laboratory results, pathological reports, and endoscopic findings of patients who underwent radical surgery for T1 CRC. We developed AI models to predict LNM using four algorithms: regularized logistic regression classifier (RLRC), random forest classifier (RFC), CatBoost classifier (CBC), and the voting classifier (VC). Four histological factors and four endoscopic findings were included to develop AI models. Areas under the receiver operating characteristics curves (AUROCs) were measured to distinguish AI model performance in accordance with the Japanese Society for Cancer of the Colon and Rectum guidelines. Results: Among 1,386 patients with T1 CRC, 173 patients (12.5%) had LNM. The AUROC values of the RLRC, RFC, CBC, and VC models for LNM prediction were significantly higher (0.673, 0.640, 0.679, and 0.677, respectively) than the 0.525 suggested in accordance with the Japanese Society for Cancer of the Colon and Rectum guidelines (vs RLRC, p<0.001; vs RFC, p=0.001; vs CBC, p<0.001; vs VC, p<0.001). The AUROC value was similar between T1 colon versus T1 rectal cancers (0.718 vs 0.615, p=0.700). The AUROC value was also similar between the initial endoscopic resection and initial surgery groups (0.581 vs 0.746, p=0.845). Conclusions AI models trained on the basis of endoscopic findings and pathological features performed well in predicting LNM in patients with T1 CRC regardless of tumor location and initial treatment method.

Background/Aims: The study investigated the incidence, risk factors, and clinical outcomes of chronic antibiotic-refractory pouchitis (CARP) in Korean patients with ulcerative colitis (UC). Methods: This single-center retrospective study included patients with UC who underwent total proctocolectomy with ileal pouch-anal anastomosis at the Asan Medical Center in Korea between January 1987 and December 2022. The primary outcomes were endoscopic remission and pouch failure. The Cox’s proportional hazard model was used to identify the risk factors for CARP. Results: The clinical data of 232 patients were analyzed. The most common cause of surgery was steroid refractoriness (50.9%), followed by dysplasia/colorectal cancer (26.7%). Among 74 patients (31.9%) with chronic pouchitis (CP), 31 (13.4%) had CARP, and 43 (18.5%) had chronic antibiotic-dependent pouchitis (CADP). The most frequent endoscopic phenotype was focal inflammation of the pouch (CP, 47.3%; CARP, 35.5%; CADP, 55.8%). Patients with CARP were less likely to use concomitant probiotics than patients with CADP (29.0% vs 72.1%, p<0.01). The endoscopic remission rate of CP, CARP, and CADP was 14.9%, 9.7%, and 18.6%, respectively.The pouch failure rate associated with CP, CARP, and CADP was 13.5%, 16.1%, and 11.6%, respectively. Current smoking status (adjusted hazard ratio [aHR], 2.96; 95% confidence interval [CI], 1.27 to 6.90; p=0.01) and previous use of biologics/small molecules (aHR, 2.40; 95% CI, 1.05 to 5.53; p=0.04) were significantly associated with CARP development. Conclusions UC patients who were current smokers and previously used biologics/small molecules had a higher risk of developing CARP. Concomitant use of probiotics was less likely to be associated with CARP development.

The Korean Enhanced Recovery After Surgery (ERAS) Committee within the Korean Society of Surgical Metabolism and Nutrition was established to develop ERAS guidelines tailored to the Korean context. This guideline focuses on creating the most current evidence-based practice guidelines for ERAS purposes, based on systematic reviews. All key questions targeted randomized controlled trials exclusively, and if fewer than 2 were available, studies employing propensity score matching were also included. Recommendations for each key question were marked with strength of recommendation and level of evidence following internal and external review processes by the committee.

Purpose: This study investigated the recurrence patterns and timing in patients with pathologic N2 (pN2) non-small cell lung cancer (NSCLC) according to the residual tumor (R) descriptor proposed by the International Association for the Study of Lung Cancer (IASLC). Materials and Methods: From 2004 to 2021, patients with pN2 NSCLC who underwent anatomical resection were analyzed according to the IASLC R criteria using medical records from a single center. Survival analysis was performed using Cox proportional hazards models. Recurrence patterns between complete (R0) and uncertain resections (R[un]) were compared. Results: In total, 1,373 patients were enrolled in this study: 576 (42.0%) in R0, 286 (20.8%) in R(un), and 511 (37.2%) in R1/R2 according to the IASLC R criteria. The most common reason for R(un) classification was positivity for the highest lymph node (88.8%). In multivariable analysis, the hazard ratios for recurrence in R(un) and R1/R2 compared to R0 were 1.18 (95% confidence interval [CI], 0.96–1.46) and 1.58 (1.31–1.90), respectively. The hazard rate curves displayed similar patterns among groups, peaking at approximately 12 months after surgery. There was a significant difference in distant recurrence patterns between R0 and R(un). Further analysis after stratification with the IASLC N2 descriptor showed significant differences in distant recurrence patterns between R0 and R(un) in patients pN2a1 and pN2a2 disease, but not in those with pN2b disease. Conclusion The IASLC R criteria has prognostic relevance in patients with pN2 NSCLC. R(un) is a highly heterogeneous group, and the involvement of the highest mediastinal lymph node can affect distant recurrence patterns.

Purpose: The International Association for the Study of Lung Cancer suggests further subdivision of pathologic N (pN) category in non–small-cell lung cancer (NSCLC) by incorporating the location and number of involved lymph node (LN) stations. We reclassified patients with the station-based N2b disease into single-zone and multi-zone N2b groups and compared survival outcomes between the groups. Materials and Methods: This retrospective study included patients with pN2 NSCLC who underwent lobectomy from 2006 to 2019. The N2 disease was subdivided into four categories: single-station N2 without N1 (N2a1), single-station N2 with N1 (N2a2), multiple-station N2 with single zone involvement (single-zone N2b), and multiple-station N2 with multiple zone involvement (multi-zone N2b). LN zones included in the subdivision of N2 disease were upper mediastinal, lower mediastinal, aortopulmonary, and subcarinal. Results: Among 996 eligible patients, 211 (21.2%), 394 (39.6%), and 391 (39.3%) were confirmed to have pN2a1, pN2a2, and pN2b disease, respectively. In multivariable analysis after adjustment for sex, age, pT category, and adjuvant chemotherapy, overall survival was significantly better with single-zone N2b disease (n=125, 12.6%) than with multi-zone N2b disease (n=266, 26.7%) (hazard ratio [HR], 0.67; 95% confidence interval [CI], 0.49 to 0.90; p=0.009) and was comparable to that of N2a2 disease (HR, 1.12; 95% CI, 0.83 to 1.49; p=0.46). Conclusion Prognosis of single-zone LN metastasis was better than that of multiple-zone LN metastasis in patients with N2b NSCLC. Along with the station-based N descriptors, zone-based descriptors might ensure optimal staging, enabling the most appropriate decision-making on adjuvant therapy for patients with pN2 NSCLC.

Objectives: . Head and neck squamous cell carcinoma (HNSCC) exhibits high recurrence rates, particularly in cases of radioresistant HNSCC (RR-HNSCC). Non-thermal plasma (NTP) therapy effectively suppresses the progression of HNSCC. However, the therapeutic mechanisms of NTP therapy in treating RR-HNSCC are not well understood. In this study, we explored the regulatory role of NTP in the RR-HNSCC signaling pathway and identified its signature genes. Methods: . After constructing two RR-HNSCC cell lines, we prepared cell lysates from cells treated or not treated with NTP-activated media (NTPAM) and performed RNA sequencing to determine their mRNA expression profiles. Based on the RNA sequencing results, we identified differentially expressed genes (DEGs), followed by a bioinformatics analysis to identify candidate molecules potentially associated with NTPAM therapy for RR-HNSCC. Results: . NTPAM reduced RR-HNSCC cell viability in vitro. RNA sequencing results indicated that NTPAM treatment activated the reactive oxygen species (ROS) pathway and induced ferroptosis in RR-HNSCC cell lines. Among the 1,924 genes correlated with radiation treatment, eight showed statistical significance in both the cell lines and The Cancer Genome Atlas (TCGA) cohort. Only five genes—ABCC3, DUSP16, PDGFB, RAF1, and THBS1—showed consistent results between the NTPAM data sequencing and TCGA data. LASSO regression analysis revealed that five genes were associated with cancer prognosis, with a hazard ratio of 2.26. In RR-HNSCC cells, NTPAM affected DUSP16, PDGFB, and THBS1 as activated markers within 6 hours, and this effect persisted for 12 hours. Furthermore, enrichment analysis indicated that these three DEGs were associated with the extracellular matrix, transforming growth factor-beta, phosphoinositide 3-kinase/protein kinase B, and mesenchymal-epithelial transition factor pathways. Conclusion . NTPAM therapy exerts cytotoxic effects in RR-HNSCC cell lines by inducing specific ROS-mediated ferroptosis. DUSP16, PDGFB, and THBS1 were identified as crucial targets for reversing the radiation resistance induced by NTPAM therapy, providing insights into the mechanisms and clinical applications of NTPAM treatment in RR-HNSCC.

Background and Objectives: The purpose of this study was to compare and analyze the 18- year change in the relative value scale (RVS) in otolaryngology in relation to other surgical departments so as to help make future policy decisions.Subjects and Method Data on RVSs and addition rates, the deparments of main managed care, frequency of practice, and number of specialists were collected for all surgeries and procedures conducted in 2004, 2008, 2013, 2018, and 2022. Among these, an analysis was conducted for nine surgical departments. The number of surgeries and procedure items, the median value of the RVS, and the usage amount (i.e., RVS of all items multiplied by the frequency of surgeries and procedures) were calculated. Results: Over the past 18 years, the increase in the number of surgeries, procedure items and RVS in otolaryngology has grown smaller than that in other surgical departments, and the usage has decreased very sharply; in essence, the usage per specialist has actually decreased compared to 18 years ago. Conclusion Compared to other departments, RVS in otorhinolaryngology has shown very little change over the past period of 18 years. It is necessary to reasonably increase the currently undervalued RVS in otorhinolaryngology, particularly focusing on surgeries and procedures.

Background and Objectives: Various distinct types of tumors can develop in the auricles; however, those have not been thoroughly studied clinically. The aim of the study is to assess the clinical nature of auricular tumors.Subjects and Method We retrospectively reviewed medical records and pathological findings in patients with auricular tumors who underwent surgical interventions at a single institution from January 2011 to October 2023. Cases in which the location of the tumor could be identified and pathological results were confirmed were included. We analyzed age, sex, tumor location and size, tumor occurrence period and causes, recurrence, and pathological results. Results: A total of 98 auricular tumors were included in the study. Auricular tumors were most commonly found on the lobule (32.3%), followed by the helix (30.1%) and the posterior auricle (15.1%). The most prevalent pathological type of auricular tumors was an epidermal cyst (45.2%), followed by keloid (21.5%). A single case of squamous cell carcinoma was reported. Eight tumors recurred following surgical resection, with five cases of keloid, two cases of epidermal cyst, and one case of squamous cell carcinoma, with an average recurrence interval of 6.1 months. Conclusion The present study assessed the largest number of auricular tumors collected in a single institution. Tumors with diverse clinical characteristics can develop in the auricle, and cosmetic considerations must be taken into account before undergoing surgical treatment. The findings of the present study could provide proper approaches to the auricular tumors.

Background and Objectives: The purpose of this study was to compare and analyze the 18- year change in the relative value scale (RVS) in otolaryngology in relation to other surgical departments so as to help make future policy decisions.Subjects and Method Data on RVSs and addition rates, the deparments of main managed care, frequency of practice, and number of specialists were collected for all surgeries and procedures conducted in 2004, 2008, 2013, 2018, and 2022. Among these, an analysis was conducted for nine surgical departments. The number of surgeries and procedure items, the median value of the RVS, and the usage amount (i.e., RVS of all items multiplied by the frequency of surgeries and procedures) were calculated. Results: Over the past 18 years, the increase in the number of surgeries, procedure items and RVS in otolaryngology has grown smaller than that in other surgical departments, and the usage has decreased very sharply; in essence, the usage per specialist has actually decreased compared to 18 years ago. Conclusion Compared to other departments, RVS in otorhinolaryngology has shown very little change over the past period of 18 years. It is necessary to reasonably increase the currently undervalued RVS in otorhinolaryngology, particularly focusing on surgeries and procedures.

Background and Objectives: Various distinct types of tumors can develop in the auricles; however, those have not been thoroughly studied clinically. The aim of the study is to assess the clinical nature of auricular tumors.Subjects and Method We retrospectively reviewed medical records and pathological findings in patients with auricular tumors who underwent surgical interventions at a single institution from January 2011 to October 2023. Cases in which the location of the tumor could be identified and pathological results were confirmed were included. We analyzed age, sex, tumor location and size, tumor occurrence period and causes, recurrence, and pathological results. Results: A total of 98 auricular tumors were included in the study. Auricular tumors were most commonly found on the lobule (32.3%), followed by the helix (30.1%) and the posterior auricle (15.1%). The most prevalent pathological type of auricular tumors was an epidermal cyst (45.2%), followed by keloid (21.5%). A single case of squamous cell carcinoma was reported. Eight tumors recurred following surgical resection, with five cases of keloid, two cases of epidermal cyst, and one case of squamous cell carcinoma, with an average recurrence interval of 6.1 months. Conclusion The present study assessed the largest number of auricular tumors collected in a single institution. Tumors with diverse clinical characteristics can develop in the auricle, and cosmetic considerations must be taken into account before undergoing surgical treatment. The findings of the present study could provide proper approaches to the auricular tumors.