Background/Aims: Early colorectal cancer (ECC) is commonly resected endoscopically. Perforation is a devastating complication of endoscopic resection. We aimed to identify the characteristics and predictive risk factors for perforation related to endoscopic resection of ECC. Methods: This nationwide retrospective multicenter study included patients with ECC who underwent endoscopic resection. We investigated the demographics, endoscopic findings at the time of treatment, and histopathological characteristics of the resected specimens. Logistic regression analysis was used to investigate the clinical factors associated with procedure-related perforations. Survival analysis was conducted to assess the impact of perforation on the overall survival of patients with ECC. Results: This study included 965 participants with a mean age of 63.4 years. The most common endoscopic treatment was conventional endoscopic mucosal resection (n=573, 59.4%), followed by conventional endoscopic submucosal dissection (n=259, 26.8%). Thirty-three patients (3.4%) experienced perforations, most of which were managed endoscopically (n=23/33, 69.7%). Patients who undergo endoscopic submucosal dissection-hybrid and precut endoscopic mucosal resection have a higher risk of perforation than those who undergo conventional endoscopic mucosal resection (odds ratio, 78.65 and 39.72, p<0.05). Procedure-related perforations were not associated with patient survival. Conclusions Perforation after endoscopic resection had no significant impact on the prognosis of ECC. The type of endoscopic resection was a crucial predictor of perforation. Large-scale prospective studies are needed to further investigate endoscopic resection of ECC.

The coronavirus disease 2019 (COVID-19) pandemic prompted the development of messenger RNA vaccines. Following extensive vaccination campaigns worldwide, several adverse reactions to these vaccines have been reported. This is a case series of unilateral lower extremity lymphedema after COVID-19 vaccination in two patients with a history of cervical cancer. An 82-year-old woman and a 68-year-old woman visited the outpatient clinic with unilateral leg edema after receiving a COVID-19 booster vaccine (BNT162b2; Pfizer-BioNTech) in the deltoid muscle. Both patients had a common history of cervical cancer treated with surgery, chemotherapy, and radiotherapy and were in complete remission. Gynecological evaluations, including laboratory and imaging studies, revealed no specific findings. Lymphoscintigraphy revealed delayed lymphatic drainage with diffuse dermal backflow in a unilateral lower extremity. This case series explores adverse reactions to COVID-19 vaccination in patients who are at high risk of developing lymphedema, providing novel data for similar clinical presentations.

Background/Aims: Early colorectal cancer (ECC) is commonly resected endoscopically. Perforation is a devastating complication of endoscopic resection. We aimed to identify the characteristics and predictive risk factors for perforation related to endoscopic resection of ECC. Methods: This nationwide retrospective multicenter study included patients with ECC who underwent endoscopic resection. We investigated the demographics, endoscopic findings at the time of treatment, and histopathological characteristics of the resected specimens. Logistic regression analysis was used to investigate the clinical factors associated with procedure-related perforations. Survival analysis was conducted to assess the impact of perforation on the overall survival of patients with ECC. Results: This study included 965 participants with a mean age of 63.4 years. The most common endoscopic treatment was conventional endoscopic mucosal resection (n=573, 59.4%), followed by conventional endoscopic submucosal dissection (n=259, 26.8%). Thirty-three patients (3.4%) experienced perforations, most of which were managed endoscopically (n=23/33, 69.7%). Patients who undergo endoscopic submucosal dissection-hybrid and precut endoscopic mucosal resection have a higher risk of perforation than those who undergo conventional endoscopic mucosal resection (odds ratio, 78.65 and 39.72, p<0.05). Procedure-related perforations were not associated with patient survival. Conclusions Perforation after endoscopic resection had no significant impact on the prognosis of ECC. The type of endoscopic resection was a crucial predictor of perforation. Large-scale prospective studies are needed to further investigate endoscopic resection of ECC.

The coronavirus disease 2019 (COVID-19) pandemic prompted the development of messenger RNA vaccines. Following extensive vaccination campaigns worldwide, several adverse reactions to these vaccines have been reported. This is a case series of unilateral lower extremity lymphedema after COVID-19 vaccination in two patients with a history of cervical cancer. An 82-year-old woman and a 68-year-old woman visited the outpatient clinic with unilateral leg edema after receiving a COVID-19 booster vaccine (BNT162b2; Pfizer-BioNTech) in the deltoid muscle. Both patients had a common history of cervical cancer treated with surgery, chemotherapy, and radiotherapy and were in complete remission. Gynecological evaluations, including laboratory and imaging studies, revealed no specific findings. Lymphoscintigraphy revealed delayed lymphatic drainage with diffuse dermal backflow in a unilateral lower extremity. This case series explores adverse reactions to COVID-19 vaccination in patients who are at high risk of developing lymphedema, providing novel data for similar clinical presentations.

The coronavirus disease 2019 (COVID-19) pandemic prompted the development of messenger RNA vaccines. Following extensive vaccination campaigns worldwide, several adverse reactions to these vaccines have been reported. This is a case series of unilateral lower extremity lymphedema after COVID-19 vaccination in two patients with a history of cervical cancer. An 82-year-old woman and a 68-year-old woman visited the outpatient clinic with unilateral leg edema after receiving a COVID-19 booster vaccine (BNT162b2; Pfizer-BioNTech) in the deltoid muscle. Both patients had a common history of cervical cancer treated with surgery, chemotherapy, and radiotherapy and were in complete remission. Gynecological evaluations, including laboratory and imaging studies, revealed no specific findings. Lymphoscintigraphy revealed delayed lymphatic drainage with diffuse dermal backflow in a unilateral lower extremity. This case series explores adverse reactions to COVID-19 vaccination in patients who are at high risk of developing lymphedema, providing novel data for similar clinical presentations.

The coronavirus disease 2019 (COVID-19) pandemic prompted the development of messenger RNA vaccines. Following extensive vaccination campaigns worldwide, several adverse reactions to these vaccines have been reported. This is a case series of unilateral lower extremity lymphedema after COVID-19 vaccination in two patients with a history of cervical cancer. An 82-year-old woman and a 68-year-old woman visited the outpatient clinic with unilateral leg edema after receiving a COVID-19 booster vaccine (BNT162b2; Pfizer-BioNTech) in the deltoid muscle. Both patients had a common history of cervical cancer treated with surgery, chemotherapy, and radiotherapy and were in complete remission. Gynecological evaluations, including laboratory and imaging studies, revealed no specific findings. Lymphoscintigraphy revealed delayed lymphatic drainage with diffuse dermal backflow in a unilateral lower extremity. This case series explores adverse reactions to COVID-19 vaccination in patients who are at high risk of developing lymphedema, providing novel data for similar clinical presentations.

Background/Aims: Early colorectal cancer (ECC) is commonly resected endoscopically. Perforation is a devastating complication of endoscopic resection. We aimed to identify the characteristics and predictive risk factors for perforation related to endoscopic resection of ECC. Methods: This nationwide retrospective multicenter study included patients with ECC who underwent endoscopic resection. We investigated the demographics, endoscopic findings at the time of treatment, and histopathological characteristics of the resected specimens. Logistic regression analysis was used to investigate the clinical factors associated with procedure-related perforations. Survival analysis was conducted to assess the impact of perforation on the overall survival of patients with ECC. Results: This study included 965 participants with a mean age of 63.4 years. The most common endoscopic treatment was conventional endoscopic mucosal resection (n=573, 59.4%), followed by conventional endoscopic submucosal dissection (n=259, 26.8%). Thirty-three patients (3.4%) experienced perforations, most of which were managed endoscopically (n=23/33, 69.7%). Patients who undergo endoscopic submucosal dissection-hybrid and precut endoscopic mucosal resection have a higher risk of perforation than those who undergo conventional endoscopic mucosal resection (odds ratio, 78.65 and 39.72, p<0.05). Procedure-related perforations were not associated with patient survival. Conclusions Perforation after endoscopic resection had no significant impact on the prognosis of ECC. The type of endoscopic resection was a crucial predictor of perforation. Large-scale prospective studies are needed to further investigate endoscopic resection of ECC.

Background/Aims: Early colorectal cancer (ECC) is commonly resected endoscopically. Perforation is a devastating complication of endoscopic resection. We aimed to identify the characteristics and predictive risk factors for perforation related to endoscopic resection of ECC. Methods: This nationwide retrospective multicenter study included patients with ECC who underwent endoscopic resection. We investigated the demographics, endoscopic findings at the time of treatment, and histopathological characteristics of the resected specimens. Logistic regression analysis was used to investigate the clinical factors associated with procedure-related perforations. Survival analysis was conducted to assess the impact of perforation on the overall survival of patients with ECC. Results: This study included 965 participants with a mean age of 63.4 years. The most common endoscopic treatment was conventional endoscopic mucosal resection (n=573, 59.4%), followed by conventional endoscopic submucosal dissection (n=259, 26.8%). Thirty-three patients (3.4%) experienced perforations, most of which were managed endoscopically (n=23/33, 69.7%). Patients who undergo endoscopic submucosal dissection-hybrid and precut endoscopic mucosal resection have a higher risk of perforation than those who undergo conventional endoscopic mucosal resection (odds ratio, 78.65 and 39.72, p<0.05). Procedure-related perforations were not associated with patient survival. Conclusions Perforation after endoscopic resection had no significant impact on the prognosis of ECC. The type of endoscopic resection was a crucial predictor of perforation. Large-scale prospective studies are needed to further investigate endoscopic resection of ECC.

Background: An international reference measurement laboratory network for creatinine (Cr) is lacking; therefore, Korea developed an independent evaluation and certification system. The in vitro diagnostics (IVD) certification program, launched in 2017, formed part of a broader Cr standardization initiative intended to enhance accuracy at the manufacturing stage. Methods: The program was designed to evaluate analytical systems, including all reagent lots, calibrators, and instrument models, twice annually. Bias, imprecision, total error (TE), and linearity were evaluated based on established acceptance criteria. A post-certification process allows submission for a second challenge and validation of corrective actions. Results: Between 2017 and 2023, 489 analytical systems were evaluated. Average acceptance rates for bias, imprecision, TE, and linearity were 70.8%, 95.9%, 87.7%, and 87.8%, respectively. The lowest acceptance rate for bias evaluation was 8.7% for the kinetic Jaffe method without compensation in 2018. Over the 7-year period, the mean absolute percentage bias (absBias%), coefficient of variation (CV), and TE were 4.62%, 1.37%,and 7.29%, respectively. The highest absBias% (7.94%) was observed in the 0.0 ≤ Cr < 1.0target value range. Since 2019, a consistent reduction in absBias% has been observed. Conclusions This program is a pioneering response to the absence of a global certification program for Cr assays. It offers significant advantages, including comprehensive evaluations, fee-free participation, and a robust post-certification process. Continuous participation and improvement efforts by manufacturers have contributed to enhanced accuracy in Cr assays.

Background/Aims: In 2019, the American Society for Gastrointestinal Endoscopy (ASGE) established clinical predictors for choledocholithiasis. Our study was designed to evaluate these predictors within the Korean clinical context, establish cutoff values, and develop a predictive model. Methods: This retrospective study analyzed patients who underwent laparoscopic cholecystectomy. The relationships between choledocholithiasis and predictors including age, blood tests, and imaging findings were assessed through univariate and multivariate logistic regression analyses. We established Korean cutoff values for these predictors and developed a scoring system for choledocholithiasis using a multivariate logistic regression. The performance of this scoring system was then compared with that of the 2019 ASGE guidelines through a receiver operating characteristic curve. Results: We established Korean cutoff values for age (>70 years), alanine aminotransferase (>26.5 U/L), aspartate aminotransferase (>28.5 U/L), gamma-glutamyl transferase (GGT; >82.5 U/L), alkaline phosphatase (ALP; >77.5 U/L), and total bilirubin (>0.95 mg/dL). In the multivariate analysis, only age >70 years, GGT >77.5 U/L, ALP >77.5 U/L, and common bile duct dilatation remained significant. We then developed a new Korean risk stratification model from the multivariate analysis, with an area under the curve of 0.777 (95% confidence interval, 0.75 to 0.81).Our model was stratified into the low-risk, intermediate-risk, and high-risk groups with the scores being <1.0, 1.0–5.5, and >5.5, respectively. Conclusions Predictors of choledocholithiasis in cholecystectomy patients and their cutoff values in Korean should be adjusted and further studies are needed to develop appropriate guidelines.