Purpose: This study aimed to evaluate the impact of declining surgical residency program enrollment on patient care and outcomes in colorectal cancer surgeries. Methods: This retrospective observational study included 676 patients (410 males; median age: 69 years) who underwent colorectal cancer surgery at Pusan National University Hospital between January 2018 and June 2024. Patients were divided into Group A (before December 31, 2023; with residents) and Group B (after January 1, 2024; without residents). All surgeries were performed by a single attending surgeon. Results: Preoperative variables were comparable between groups. Group A had more emergency and open surgeries, and a higher proportion of advanced-stage cancers. Overall complication rates were similar, but Group B had a longer hospital stay (9.72 days vs. 11.95 days). Specific complications such as anastomotic leakage and surgical site infections differed significantly. The overall number of surgical procedures declined markedly in 2024 compared to 2018 (77.1% vs. 49.9%). Conclusion The absence of residents did not increase overall complication rates but was associated with longer hospital stays and shifts in clinical practice. Greater reliance on attending surgeons contributed to more defensive decision-making and conservative patient management. Addressing these issues requires systemic reforms, including multidisciplinary collaboration and legal protections to improve surgical care.

Purpose: This study aimed to evaluate the impact of declining surgical residency program enrollment on patient care and outcomes in colorectal cancer surgeries. Methods: This retrospective observational study included 676 patients (410 males; median age: 69 years) who underwent colorectal cancer surgery at Pusan National University Hospital between January 2018 and June 2024. Patients were divided into Group A (before December 31, 2023; with residents) and Group B (after January 1, 2024; without residents). All surgeries were performed by a single attending surgeon. Results: Preoperative variables were comparable between groups. Group A had more emergency and open surgeries, and a higher proportion of advanced-stage cancers. Overall complication rates were similar, but Group B had a longer hospital stay (9.72 days vs. 11.95 days). Specific complications such as anastomotic leakage and surgical site infections differed significantly. The overall number of surgical procedures declined markedly in 2024 compared to 2018 (77.1% vs. 49.9%). Conclusion The absence of residents did not increase overall complication rates but was associated with longer hospital stays and shifts in clinical practice. Greater reliance on attending surgeons contributed to more defensive decision-making and conservative patient management. Addressing these issues requires systemic reforms, including multidisciplinary collaboration and legal protections to improve surgical care.

Purpose: This study aimed to evaluate the impact of declining surgical residency program enrollment on patient care and outcomes in colorectal cancer surgeries. Methods: This retrospective observational study included 676 patients (410 males; median age: 69 years) who underwent colorectal cancer surgery at Pusan National University Hospital between January 2018 and June 2024. Patients were divided into Group A (before December 31, 2023; with residents) and Group B (after January 1, 2024; without residents). All surgeries were performed by a single attending surgeon. Results: Preoperative variables were comparable between groups. Group A had more emergency and open surgeries, and a higher proportion of advanced-stage cancers. Overall complication rates were similar, but Group B had a longer hospital stay (9.72 days vs. 11.95 days). Specific complications such as anastomotic leakage and surgical site infections differed significantly. The overall number of surgical procedures declined markedly in 2024 compared to 2018 (77.1% vs. 49.9%). Conclusion The absence of residents did not increase overall complication rates but was associated with longer hospital stays and shifts in clinical practice. Greater reliance on attending surgeons contributed to more defensive decision-making and conservative patient management. Addressing these issues requires systemic reforms, including multidisciplinary collaboration and legal protections to improve surgical care.

Purpose: This study aimed to evaluate the impact of declining surgical residency program enrollment on patient care and outcomes in colorectal cancer surgeries. Methods: This retrospective observational study included 676 patients (410 males; median age: 69 years) who underwent colorectal cancer surgery at Pusan National University Hospital between January 2018 and June 2024. Patients were divided into Group A (before December 31, 2023; with residents) and Group B (after January 1, 2024; without residents). All surgeries were performed by a single attending surgeon. Results: Preoperative variables were comparable between groups. Group A had more emergency and open surgeries, and a higher proportion of advanced-stage cancers. Overall complication rates were similar, but Group B had a longer hospital stay (9.72 days vs. 11.95 days). Specific complications such as anastomotic leakage and surgical site infections differed significantly. The overall number of surgical procedures declined markedly in 2024 compared to 2018 (77.1% vs. 49.9%). Conclusion The absence of residents did not increase overall complication rates but was associated with longer hospital stays and shifts in clinical practice. Greater reliance on attending surgeons contributed to more defensive decision-making and conservative patient management. Addressing these issues requires systemic reforms, including multidisciplinary collaboration and legal protections to improve surgical care.

Abdominal actinomycosis is a rare chronic infection caused by Actinomyces species that often mimics advanced intra-abdominal malignancies, making early diagnosis difficult. We report the case of an 82-year-old woman who presented with intermittent left abdominal pain and a palpable mass. Imaging revealed a large pericolic mass with suspected invasion of the stomach and abdominal wall, raising strong suspicion for colon cancer with regional lymph node involvement and possible peritoneal carcinomatosis. Core needle biopsy results suggested an inflammatory myofibroblastic tumor. Because malignancy could not be ruled out, surgical resection—comprising extended left hemicolectomy, gastric wedge resection, and abdominal wall excision—was performed. Histopathological examination demonstrated multiple abscesses containing gram-positive bacilli, consistent with actinomycosis. The patient received high-dose intravenous penicillin followed by prolonged oral therapy and remained symptomfree at the 1-year follow-up. This case underscores the diagnostic challenge of abdominopelvic actinomycosis, particularly when it involves multiple organs and radiologically mimics invasive malignancy. Clinicians should consider this rare entity in the differential diagnosis of tumorlike abdominal lesions, especially when radiologic or endoscopic findings are atypical, to avoid unnecessary aggressive interventions and ensure appropriate management.

Purpose: Risk factors predicting distant metastasis (DM) in extrahepatic bile duct cancer (EHBDC) patients treated with curative resection were investigated. Materials and Methods: Medical records of 1,418 EHBDC patients undergoing curative resection between Jan 2000 and Dec 2015 from 14 institutions were reviewed. After resection, 924 patients (67.6%) were surveilled without adjuvant therapy, 297 (21.7%) were treated with concurrent chemoradiotherapy (CCRT) and 148 (10.8%) with CCRT followed by chemotherapy. To exclude the treatment effect from innate confounders, patients not treated with adjuvant therapy were evaluated. Results: After a median follow-up of 36.7 months (range, 2.7 to 213.2 months), the 5-year distant metastasis-free survival (DMFS) rate was 57.7%. On multivariate analysis, perihilar or diffuse tumor (hazard ratio [HR], 1.391; p=0.004), poorly differentiated histology (HR, 2.014; p < 0.001), presence of perineural invasion (HR, 1.768; p < 0.001), positive nodal metastasis (HR, 2.670; p < 0.001) and preoperative carbohydrate antigen (CA) 19-9 ≥ 37 U/mL (HR, 1.353; p < 0.001) were significantly associated with inferior DMFS. The DMFS rates significantly differed according to the number of these risk factors. For validation, patients who underwent adjuvant therapy were evaluated. In patients with ≥ 3 factors, additional chemotherapy after CCRT resulted in a superior DMFS compared with CCRT alone (5-year rate, 47.6% vs. 27.7%; p=0.001), but the benefit of additional chemotherapy was not observed in patients with 0-2 risk factors. Conclusion Tumor location, histologic differentiation, perineural invasion, lymph node metastasis, and preoperative CA 19-9 level predicted DM risk in resected EHBDC. These risk factors might help identifying a subset of patients who could benefit from additional chemotherapy after resection.

Purpose: This subgroup analysis of the Korean subset of patients in the phase 3 LASER301 trial evaluated the efficacy and safety of lazertinib versus gefitinib as first-line therapy for epidermal growth factor receptor mutated (EGFRm) non–small cell lung cancer (NSCLC). Materials and Methods: Patients with locally advanced or metastatic EGFRm NSCLC were randomized 1:1 to lazertinib (240 mg/day) or gefitinib (250 mg/day). The primary endpoint was investigator-assessed progression-free survival (PFS). Results: In total, 172 Korean patients were enrolled (lazertinib, n=87; gefitinib, n=85). Baseline characteristics were balanced between the treatment groups. One-third of patients had brain metastases (BM) at baseline. Median PFS was 20.8 months (95% confidence interval [CI], 16.7 to 26.1) for lazertinib and 9.6 months (95% CI, 8.2 to 12.3) for gefitinib (hazard ratio [HR], 0.41; 95% CI, 0.28 to 0.60). This was supported by PFS analysis based on blinded independent central review. Significant PFS benefit with lazertinib was consistently observed across predefined subgroups, including patients with BM (HR, 0.28; 95% CI, 0.15 to 0.53) and those with L858R mutations (HR, 0.36; 95% CI, 0.20 to 0.63). Lazertinib safety data were consistent with its previously reported safety profile. Common adverse events (AEs) in both groups included rash, pruritus, and diarrhoea. Numerically fewer severe AEs and severe treatment–related AEs occurred with lazertinib than gefitinib. Conclusion Consistent with results for the overall LASER301 population, this analysis showed significant PFS benefit with lazertinib versus gefitinib with comparable safety in Korean patients with untreated EGFRm NSCLC, supporting lazertinib as a new potential treatment option for this patient population.

Bovine viral diarrhea virus (BVDV), which is prevalent worldwide, is one of the most important viral pathogens and causes substantial economic loss to the livestock industry. Despite its importance, BVDV is largely unnoticed in the Republic of Korea (ROK). In this study, we report the case of a steer with BVDV that died suddenly due to severe enteritis. Two 1-year-old Korean indigenous cattle in the same herd presented severe hemorrhagic diarrhea. Case 1 had severe dehydration and died after 3 days, whereas case 2 had anorexia, depression, and severe diarrhea with mucus and blood. Only case 2 was necropsied, and BVDV2a was detected in the tissues of its alimentary tract. Gross lesions, including erosion, ulceration, and extensive hemorrhage, were observed in the digestive tract mucosa. Immunohistochemistry revealed marked positive staining for BVDV2a antigen in the large intestine. This report describes the first case of hemorrhagic disease caused by acute BVDV2a infection, which is characterized by high mortality in Korean indigenous cattle. This study will help establish vaccination and control strategies for BVDV in the ROK.

Background/Aims: The prognostic value of a comprehensive geriatric assessment (CGA) for the management of older small cell lung cancer (SCLC) patients remains to be established. Methods: A retrospective cohort enrolled 21 SCLC patients over 65 years from March 2018 to 2019 at the Yonsei Cancer Center. The CGA included the following instruments: frailty, body mass index, sarcopenia (circumference of arm and calf, Timed Up and Go test, grip strength), comorbidity, polypharmacy, activities of daily living (ADL), Instrumental ADL, nutrition, depression, and cognitive function. The correlations of oncological and geriatric variables with overall survival (OS) were determined. The log-rank test with Cox model and Kaplan-Meier method were used for the analysis. Results: The median age was 75 years (range, 67 to 85). All patients had the Eastern Cooperative Oncology Group performance status 0–2. The median survival was 9.93 months (range, 1.53 to 36.30). Among CGA parameters, ADL and nutritional status had significant differences in OS in univariate analysis. In multivariate analysis, only nutritional status was independently associated with survival (hazard ratio, 0.17; 95% confidence interval, 0.05 to 0.57). Median OS for low nutritional status was 5.63 months and the normal nutrition group was 15.5 months (p = 0.004). Conclusions Pre-treatment nutritional status measured by CGA appears to be a predictor of OS in older SCLC patients. However, for further generalization of the implication of CGA in SCLC, a larger scale study with prospective design is strongly needed.