Purpose: We aimed to evaluate the precision of preoperative colonoscopic tattooing and intraoperative colonoscopic tumor localization in determining distal surgical margins for leftsided colorectal cancer surgery. Methods: This retrospective study included 30 patients who underwent laparoscopic colorectal surgery, preoperative colonoscopic tattooing, and intraoperative colonoscopic localization for colorectal cancer at our center between July 2020 and March 2024. Clinical data were collected, and the precision of these methods was assessed by measuring the differences between the target resection margin and the actual pathological resection margin. Results: In four patient cases, the indocyanine green tattoo was not visible in the laparoscopic surgical field. The average stained length of the tattoo was 2.89 cm, with a mean distance of 1.18 cm between the low margin of the tattoo and the cancer. The difference between the target distal resection margin by intraoperative colonoscopic localization and the actual pathological resection margin was 0.88 cm. No complications related to the intraoperative colonoscopy were observed. Conclusion Preoperative tattooing showed limitations, such as spreading and occasional invisibility. Intraoperative colonoscopic localization proved to be an effective method for achieving more precise distal surgical margins in left-sided colorectal cancer surgery.

Purpose: We aimed to evaluate the precision of preoperative colonoscopic tattooing and intraoperative colonoscopic tumor localization in determining distal surgical margins for leftsided colorectal cancer surgery. Methods: This retrospective study included 30 patients who underwent laparoscopic colorectal surgery, preoperative colonoscopic tattooing, and intraoperative colonoscopic localization for colorectal cancer at our center between July 2020 and March 2024. Clinical data were collected, and the precision of these methods was assessed by measuring the differences between the target resection margin and the actual pathological resection margin. Results: In four patient cases, the indocyanine green tattoo was not visible in the laparoscopic surgical field. The average stained length of the tattoo was 2.89 cm, with a mean distance of 1.18 cm between the low margin of the tattoo and the cancer. The difference between the target distal resection margin by intraoperative colonoscopic localization and the actual pathological resection margin was 0.88 cm. No complications related to the intraoperative colonoscopy were observed. Conclusion Preoperative tattooing showed limitations, such as spreading and occasional invisibility. Intraoperative colonoscopic localization proved to be an effective method for achieving more precise distal surgical margins in left-sided colorectal cancer surgery.

Purpose: We aimed to evaluate the precision of preoperative colonoscopic tattooing and intraoperative colonoscopic tumor localization in determining distal surgical margins for leftsided colorectal cancer surgery. Methods: This retrospective study included 30 patients who underwent laparoscopic colorectal surgery, preoperative colonoscopic tattooing, and intraoperative colonoscopic localization for colorectal cancer at our center between July 2020 and March 2024. Clinical data were collected, and the precision of these methods was assessed by measuring the differences between the target resection margin and the actual pathological resection margin. Results: In four patient cases, the indocyanine green tattoo was not visible in the laparoscopic surgical field. The average stained length of the tattoo was 2.89 cm, with a mean distance of 1.18 cm between the low margin of the tattoo and the cancer. The difference between the target distal resection margin by intraoperative colonoscopic localization and the actual pathological resection margin was 0.88 cm. No complications related to the intraoperative colonoscopy were observed. Conclusion Preoperative tattooing showed limitations, such as spreading and occasional invisibility. Intraoperative colonoscopic localization proved to be an effective method for achieving more precise distal surgical margins in left-sided colorectal cancer surgery.

Colorectal cancer is the third most common cancer in Korea and the third leading cause of death from cancer. Treatment outcomes for colon cancer are steadily improving due to national health screening programs with advances in diagnostic methods, surgical techniques, and therapeutic agents.. The Korea Colon Cancer Multidisciplinary (KCCM) Committee intends to provide professionals who treat colon cancer with the most up-to-date, evidence-based practice guidelines to improve outcomes and help them make decisions that reflect their patients’ values and preferences. These guidelines have been established by consensus reached by the KCCM Guideline Committee based on a systematic literature review and evidence synthesis and by considering the national health insurance system in real clinical practice settings. Each recommendation is presented with a recommendation strength and level of evidence based on the consensus of the committee.

Purpose: Heterogeneous human epidermal growth factor receptor 2 (HER2) overexpression in gastric cancer may lead to a misdiagnosis of HER2 status. Accurate assessment of HER2 status is essential for optimal treatment as novel HER2-directed agents are being investigated in various clinical settings. We evaluated the usefulness of HER2 re-assessment following progression on first-line treatment in initially HER2-negative advanced gastric cancer (AGC) patients. Materials and Methods: We enrolled 177 patients with baseline HER2-negative AGC and performed HER2 re-assessment after progression on first-line treatment from February 2012 to June 2016 at Asan Medical Center, Seoul, Korea. The re-assessed HER2 status was analyzed with baseline HER2 status and clinical characteristics. Results: The median age was 54 years (range, 24 to 80 years), and 123 patients (69.5%) were men. Seven patients (4.0%) were HER2-positive on the re-assessment. Patients with baseline HER2 negativity confirmed by a single test (n=100) had a higher HER2-positive re-assessment rate compared to those who had repeated baseline testing (n=77) (5.0% vs. 2.6%). Among the patients with single baseline HER2 testing, the rate was higher in patients with baseline HER2 immunohistochemistry (IHC) 1+ compared to those with IHC 0 (13.4% vs. 3.6%). Conclusion Overall, 4.0% of patients with baseline HER2-negative AGC were HER2-positive on re-assessment, and the HER2-positive re-assessment rate was higher among patients who had a single test at baseline. HER2 re assessment may be considered for initially HER2-negative patients to determine their eligibility for HER2-directed therapy, particularly if their HER2 negativity was determined by a single test, especially if they had a single baseline HER2 IHC 1+ test.

Purpose: The Avoid Axillary Sentinel Lymph Node Biopsy After Neoadjuvant Chemotherapy (ASLAN) trial aims to demonstrate the oncologic safety of omitting axillary surgery in patients with excellent response after neoadjuvant chemotherapy (NACT) for early human epidermal growth factor 2 (HER2)-positive (+)/triple-negative breast cancer (TNBC) who have undergone breast-conserving surgery (BCS) and adjuvant radiotherapy. The ASLAN trial will provide crucial information that could change the procedure in highly selected patients undergoing axillary surgery after NACT. Methods ASLAN is a prospective, multicenter, and single-arm surgical trial. The recruitment will be conducted among five tertiary care hospitals in the Republic of Korea. The total number of patients to be recruited will be 178, and we plan to complete patient enrollment by December 2023. The enrollment is considered among patients with HER2+ breast cancer (BC) or TNBC at clinical stage T1–3N0–1M0 who are expected to achieve breast pathological complete response (BpCR) based on a combination of radiologic imaging and physical examination after NACT. BCS was performed on eligible patients. After BCS, patients who showed BpCR were enrolled with the omission of sentinel lymph node biopsy (SLNB). The primary study endpoint upon completion of this trial is 5-year recurrence-free survival, and the secondary endpoints include the 5-year ipsilateral breast tumor recurrence interval, 5-year ipsilateral axillary recurrence interval, 5-year distant metastasis-free survival, 5-year BC-specific survival, 5-year overall survival, 5-year contralateral BC-free survival, re-operation rate according to breast biopsy after NACT, adverse events within 5 years, and quality of life.Discussion: Several clinical trials are currently underway to determine whether SLNB can be omitted after NACT in patients with HER2+ BC or TNBC that are expected to achieve pathologic complete response. The ASLAN trial is expected to provide valuable clues regarding the feasibility of omitting axillary surgery in highly selected patients.

Objective: This study examined dyslipidemias in patients hospitalized with acute coronary syndrome, the changes, and the differences in the lipid profiles, and assessed whether these findings could serve as valuable emergency tests. Methods: From March 2021 to February 2023, a study was conducted on patients who visited the emergency room and were hospitalized with acute coronary syndrome. The total cholesterol, high-density lipoprotein (HDL), low-density lipoprotein (LDL), and triglycerides were examined. The patients were classified as unstable angina, non-ST-elevation myocardial infarction (non-STEMI), and ST-elevation myocardial infarction (STEMI) for comparison. Results: The study included 401 patients, among whom 58 (14.5%) had unstable angina, 138 (34.4%) had a nonSTEMI, and 205 (51.1%) had an STEMI. Comparisons among the three groups based on test results revealed increases in the total cholesterol (P=0.002) and LDL (P<0.0001), but no significant differences in the HDL (P=0.920) and triglycerides (P=0.293). A notable difference was observed in LDL (P=0.020) when comparing the normal and abnormal lipid profile groups. Conclusion As the disease progressed with unstable angina, non-STEMI, and STEMI, the total cholesterol and LDL increased. In the case of LDL, differences were observed between the normal and elevated groups and as the disease advanced. The lipid profiles in the emergency room are suitable for emergency tests for patients with acute coronary syndrome.

Objective: To investigate the effects of dietary habits on general and abdominal obesity in community-dwelling patients with schizophrenia spectrum disorder according to sex. Methods: A total of 270 patients with schizophrenia spectrum disorder registered at mental health welfare centers and rehabilitation facilities were recruited. General obesity was defined as a body mass index ≥ 30 kg/m 2 , and abdominal obesity was defined as a waist circumstance ≥ 90 cm in men and ≥ 85 cm in women. Dietary habits were evaluated using dietary guidelines published by the Korean Ministry of Health and Welfare. Demographic and clinical characteristics along with dietary habits and information related to obesity were collected. Factors related to obesity were evaluated separately by sex. Results: Dietary habits differed according to sex, in that scores for healthy eating habits were lower in men than in women. In men, the prevalences of general and abdominal obesity were 17.0% and 37.3%, respectively. In women, the prevalences of general and abdominal obesity were 23.1% and 38.5%, respectively. Regression analysis showed that the scores of regular eating habits were negatively associated with general and abdominal obesity in men, and the scores of healthy eating habits were negatively associated with general and abdominal obesity in women. Conclusion Among patients with schizophrenia, regular eating habits might reduce the risk of obesity in men, and healthy eating habits might reduce the risk of obesity in women. Nutrition education should be provided to community-dwelling patients with schizophrenia to prevent obesity in this population.

Objective: : With the recent increase in mechanical thrombectomy (MT) for acute ischemic stroke (AIS), the role of neurosurgeons in AIS treatment has become increasingly important. This study aimed to assess the outcomes of patients with AIS treated by neurosurgeons and neurologists in the emergency room (ER) of a tertiary hospital in South Korea. Methods: : From January 2020 to June 2021, 536 patients with AIS within 24 hours of symptom onset were admitted to our hospital via the ER. Based on the type of doctors who provided initial care for AIS in the ER, patients were divided into two groups : (a) neurosurgeon group (n=119, 22.2%) and (b) neurologist group (n=417, 77.8%). Results: : Intravenous tissue plasminogen activator (tPA) was administered in 82 (15.3%) of 536 patients (n=17 [14.3%] in the neurosurgeon group and n=65 [15.6%] in the neurologist group). The door-to-tPA time was not significantly different between both groups (median, 53 minutes; interquartile range [IQR], 45–58 vs. median, 54 minutes; IQR, 46–74; p=0.372). MT was performed in 69 patients (12.9%) (n=25, 36.2% in the neurosurgeon group and n=44, 63.8% in the neurologist group). The neurosurgeon group achieved a shorter door-to-puncture time than the neurologist group (median, 115 minutes; IQR, 107–151 vs. median, 162 minutes; IQR, 117–189; p=0.049). Good clinical outcomes (3-month modified Rankin Scale 0–2) did not differ significantly between the two groups (96/119 [80.7%] vs. 322/417 [77.2%], p=0.454). Conclusion : The neurosurgeon group showed similar door-to-treatment time and clinical outcomes to the neurologist group in patients with AIS in the ER. This study suggests that neurosurgeons have comparable abilities to care for patients with AIS in the ER.

Purpose: This study aimed to report the final analysis of time-on-treatment (TOT) and overall survival (OS) in patients with advanced-stage epidermal growth factor receptor (EGFR)+ non–small cell lung cancer (NSCLC) who received sequential afatinib and osimertinib and to compare the outcomes with other second-line regimens (comparator group). Materials and Methods: In this updated report, the existing medical records were reviewed and rechecked. TOT and OS were updated and analyzed according to clinical features using the Kaplan-Meier method and log-rank test. TOT and OS were compared with those of the comparator group, in which most patients received pemetrexed-based treatments. A multivariable Cox proportional hazard model was used to evaluate features that could affect survival outcomes. Results: The median observation time was 31.0 months. The follow-up period was extended to 20 months. A total of 401 patients who received first-line afatinib were analyzed (166 with T790M+ and second-line osimertinib, and 235 with unproven T790M and other second-line agents). Median TOTs on afatinib and osimertinib were 15.0 months (95% confidence interval [CI], 14.0 to 16.1) and 11.9 months (95% CI, 8.9 to 14.6), respectively. The median OS in the osimertinib group was 54.3 months (95% CI, 46.7 to 61.9), much longer than that in the comparator group. In patients who received osimertinib, the OS was longest with Del19+ (median, 59.1; 95% CI, 48.7 to 69.5). Conclusion This is one of the largest real-world studies reporting the encouraging activity of sequential afatinib and osimertinib in Asian patients with EGFR+ NSCLC who acquired the T790M mutation, particularly Del19+.