Rectal cancer, which accounts for approximately 40% of colorectal cancers, remains a major clinical concern. Recent advances in diagnostic imaging, surgical techniques, radiotherapy, and systemic treatment have steadily improved rectal cancer outcomes. Considering this, the Korean Rectal Cancer Multidisciplinary (KRCM) Committee has aimed to provide clinicians and policymakers with up-to-date, evidence-based clinical practice guidelines to support optimal decision-making, reflecting current evidence, the Korean healthcare context, and patient values and preferences. The Clinical Practice Guidelines for Rectal Cancer version 2.0 were developed through multidisciplinary collaboration with related academic societies, building upon and updating the KRCM Clinical Practice Guidelines version 1.0 (titled “Multidisciplinary guidelines for the management of rectal cancer”). These consensus guidelines of the KRCM were established based on a comprehensive literature review, evidence synthesis, with recommendation development guided by the GRADE (Grading of Recommendations Assessment, Development and Evaluation) methodology, and consideration of applicability in real-world clinical practice under the national health insurance system. Each recommendation has been presented with its strength and level of evidence.

Background/Aims: Despite of the coronavirus disease 2019 (COVID-19) pandemic, there is little data regarding its impact on colorectal cancer (CRC)-related clinical practice. This study aimed to assess the changes in its impact during the COVID-19 pandemic. Methods: This was a retrospective national population-based study using the Health Insurance Review and Assessment database from January 2019 to December 2021. The number of patients in 2020 and 2021 was compared with those in 2019 for the diagnostic and therapeutic colonoscopy, CRC-related operation, and any treatment for CRC. Results: The annual number of patients undergoing diagnostic colonoscopies decreased by 6.9% in 2020 but increased 8.1% in 2021, compared to those in 2019; number of patients undergoing therapeutic colonoscopies increased by 6.0% and 37.7% in 2020 and 2021, respectively; number of patients operated for CRC decreased by 4.2% in 2020 and increased by 2.3% in 2021. The number of patients treated for CRC decreased by 2.8% in 2020 and increased by 4.4% in 2021. Diagnostic and therapeutic colonoscopies and any CRC-related treatment decreased by 43.8%, 37.5%, and 11.3% in March 2020, during the first surge of COVID-19, but increased by 26.0%, 58.1%, and 9.5% in June 2021, respectively. CRC-related operations decreased by 24.1% in April 2020 and increased by 12.6% in August 2021. Conclusions Negative impact of the COVID-19 pandemic on clinical practices related to CRC completely recovered within second year. It could be considered for the development of an optimal strategy on CRC management in response to the pandemic-driven crisis.

Background/Aims: Despite of the coronavirus disease 2019 (COVID-19) pandemic, there is little data regarding its impact on colorectal cancer (CRC)-related clinical practice. This study aimed to assess the changes in its impact during the COVID-19 pandemic. Methods: This was a retrospective national population-based study using the Health Insurance Review and Assessment database from January 2019 to December 2021. The number of patients in 2020 and 2021 was compared with those in 2019 for the diagnostic and therapeutic colonoscopy, CRC-related operation, and any treatment for CRC. Results: The annual number of patients undergoing diagnostic colonoscopies decreased by 6.9% in 2020 but increased 8.1% in 2021, compared to those in 2019; number of patients undergoing therapeutic colonoscopies increased by 6.0% and 37.7% in 2020 and 2021, respectively; number of patients operated for CRC decreased by 4.2% in 2020 and increased by 2.3% in 2021. The number of patients treated for CRC decreased by 2.8% in 2020 and increased by 4.4% in 2021. Diagnostic and therapeutic colonoscopies and any CRC-related treatment decreased by 43.8%, 37.5%, and 11.3% in March 2020, during the first surge of COVID-19, but increased by 26.0%, 58.1%, and 9.5% in June 2021, respectively. CRC-related operations decreased by 24.1% in April 2020 and increased by 12.6% in August 2021. Conclusions Negative impact of the COVID-19 pandemic on clinical practices related to CRC completely recovered within second year. It could be considered for the development of an optimal strategy on CRC management in response to the pandemic-driven crisis.

Background/Aims: Despite of the coronavirus disease 2019 (COVID-19) pandemic, there is little data regarding its impact on colorectal cancer (CRC)-related clinical practice. This study aimed to assess the changes in its impact during the COVID-19 pandemic. Methods: This was a retrospective national population-based study using the Health Insurance Review and Assessment database from January 2019 to December 2021. The number of patients in 2020 and 2021 was compared with those in 2019 for the diagnostic and therapeutic colonoscopy, CRC-related operation, and any treatment for CRC. Results: The annual number of patients undergoing diagnostic colonoscopies decreased by 6.9% in 2020 but increased 8.1% in 2021, compared to those in 2019; number of patients undergoing therapeutic colonoscopies increased by 6.0% and 37.7% in 2020 and 2021, respectively; number of patients operated for CRC decreased by 4.2% in 2020 and increased by 2.3% in 2021. The number of patients treated for CRC decreased by 2.8% in 2020 and increased by 4.4% in 2021. Diagnostic and therapeutic colonoscopies and any CRC-related treatment decreased by 43.8%, 37.5%, and 11.3% in March 2020, during the first surge of COVID-19, but increased by 26.0%, 58.1%, and 9.5% in June 2021, respectively. CRC-related operations decreased by 24.1% in April 2020 and increased by 12.6% in August 2021. Conclusions Negative impact of the COVID-19 pandemic on clinical practices related to CRC completely recovered within second year. It could be considered for the development of an optimal strategy on CRC management in response to the pandemic-driven crisis.

Pediatric hypertension (HTN) is a significant, growing health concern worldwide and also in Korea. Diagnosis, evaluation, and treatment of HTN in Korean children and adolescents are uncertain due to limitations in using the current international guidelines, since the recommendations by the American Academy of Pediatrics (AAP) and European Society of Hypertension (ESH) guidelines differ. Furthermore, these are guidelines for Western youth, who are racially and ethnically different from Koreans. In addition, reference blood pressure values for all pediatric age groups, which are essential for the diagnosis of HTN according to these two guidelines, are absent in Korea. Therefore, HTN guidelines for Korean children and adolescents should be established. The Korean Working Group of Pediatric Hypertension established clinical guidelines for the diagnosis, evaluation, and management of HTN in Korean children and adolescents. These guidelines were based on reported clinical evidence, expert recommendations, and AAP and ESH guidelines. The characteristics of Korean youth and the Korean medical and insurance system were considered during the establishment of the guidelines. By providing recommendations suitable for Korean youth, these guidelines will help in the prevention and management of childhood HTN, thus relieving the burden of cardiovascular disease in adulthood in Korea.

Background/Aims: The use of 1-L polyethylene glycol with ascorbate (PEG/Asc) and oral sulfate tablets (OST) as low-volume bowel preparation agents has gradually increased. However, these agents may induce acute gastropathy during bowel preparation, particularly in elderly populations. This study aimed to compare the incidence of acute gastropathy of 1-L PEG/Asc and OST according to age, as well as efficacy and safety. Methods: This retrospective study included patients who underwent esophagogastroduodenoscopy (EGD) and colonoscopy for screening on the same day and underwent bowel preparation using OST or 1-L PEG/Asc. We collected EGD findings related to acute gastropathy, bowel-cleansing score using the Boston Bowel Preparation Scale (BBPS), polyp or adenoma detection rate (ADR), and laboratory parameters. Results: Of 4,711 patients, 1,758, 2,241, and 712 were in the younger (18–49 years), middle-aged (50–64 years), and older (≥65 years) groups, respectively. In all age groups, the OST group had higher rates of acute gastropathy than the 1-L PEG/Asc group. The younger-, middle-, and older-aged groups had OST and 1-L PEG/Asc usage rates of 42.9% and 11.6%, 41.2% and 16.0%, and 41.5% and 16.4%, respectively. Notably, in the younger group, the total BBPS and ADR scores were significantly higher in the OST group than in the 1-L PEG/Asc group; however, these did not differ in the other age groups. Conclusions Acute gastropathy was more strongly associated with OST than with 1-L PEG/Asc in all age groups. Therefore, physicians should consider acute gastropathy associated with low-volume agents in all age groups when performing bowel preparation.

Exposure to storage mite (SM) and house dust mite (HDM) allergens is a risk factor for sensitization and asthma development; however, the related immune responses and their pathology have not been fully investigated. The HDMs Dermatophagoides farinae and Dermatophagoides pteronyssinus and SM Tyrophagus putrescentiae are potent allergens that induce asthma. Most SM-related studies have focused on the allergic reactions of individuals by measuring their immunoglobulin (Ig)E expression. Considering the limited research on this topic, the present study aims to investigate the differences in the immune responses induced by HDMs and SMs and histologically analyze lung tissues in a mouse asthma model to understand the differential effects of HDM and SM. The results revealed that all mite species induced airway inflammation. Mice challenged with T. putrescentiae had the highest airway resistance and total cell, eosinophil, and neutrophil counts in the bronchoalveolar lavage fluid (BALF). The SM-sensitized groups showed more severe lesions and mucus hypersecretions than the HDM-sensitized groups. Although the degree of HDM and SM exposure was the same, the damage to the respiratory lung tissue was more severe in SM-exposed mice, which resulted in excessive mucin secretion and increased fibrosis. Furthermore, these findings suggest that SM sensitization induces a more significant hypersensitivity response in mucosal immunity than HDM sensitization in asthma models.

Background/Aims: The use of 1-L polyethylene glycol with ascorbate (PEG/Asc) and oral sulfate tablets (OST) as low-volume bowel preparation agents has gradually increased. However, these agents may induce acute gastropathy during bowel preparation, particularly in elderly populations. This study aimed to compare the incidence of acute gastropathy of 1-L PEG/Asc and OST according to age, as well as efficacy and safety. Methods: This retrospective study included patients who underwent esophagogastroduodenoscopy (EGD) and colonoscopy for screening on the same day and underwent bowel preparation using OST or 1-L PEG/Asc. We collected EGD findings related to acute gastropathy, bowel-cleansing score using the Boston Bowel Preparation Scale (BBPS), polyp or adenoma detection rate (ADR), and laboratory parameters. Results: Of 4,711 patients, 1,758, 2,241, and 712 were in the younger (18–49 years), middle-aged (50–64 years), and older (≥65 years) groups, respectively. In all age groups, the OST group had higher rates of acute gastropathy than the 1-L PEG/Asc group. The younger-, middle-, and older-aged groups had OST and 1-L PEG/Asc usage rates of 42.9% and 11.6%, 41.2% and 16.0%, and 41.5% and 16.4%, respectively. Notably, in the younger group, the total BBPS and ADR scores were significantly higher in the OST group than in the 1-L PEG/Asc group; however, these did not differ in the other age groups. Conclusions Acute gastropathy was more strongly associated with OST than with 1-L PEG/Asc in all age groups. Therefore, physicians should consider acute gastropathy associated with low-volume agents in all age groups when performing bowel preparation.

Background/Aims: The use of 1-L polyethylene glycol with ascorbate (PEG/Asc) and oral sulfate tablets (OST) as low-volume bowel preparation agents has gradually increased. However, these agents may induce acute gastropathy during bowel preparation, particularly in elderly populations. This study aimed to compare the incidence of acute gastropathy of 1-L PEG/Asc and OST according to age, as well as efficacy and safety. Methods: This retrospective study included patients who underwent esophagogastroduodenoscopy (EGD) and colonoscopy for screening on the same day and underwent bowel preparation using OST or 1-L PEG/Asc. We collected EGD findings related to acute gastropathy, bowel-cleansing score using the Boston Bowel Preparation Scale (BBPS), polyp or adenoma detection rate (ADR), and laboratory parameters. Results: Of 4,711 patients, 1,758, 2,241, and 712 were in the younger (18–49 years), middle-aged (50–64 years), and older (≥65 years) groups, respectively. In all age groups, the OST group had higher rates of acute gastropathy than the 1-L PEG/Asc group. The younger-, middle-, and older-aged groups had OST and 1-L PEG/Asc usage rates of 42.9% and 11.6%, 41.2% and 16.0%, and 41.5% and 16.4%, respectively. Notably, in the younger group, the total BBPS and ADR scores were significantly higher in the OST group than in the 1-L PEG/Asc group; however, these did not differ in the other age groups. Conclusions Acute gastropathy was more strongly associated with OST than with 1-L PEG/Asc in all age groups. Therefore, physicians should consider acute gastropathy associated with low-volume agents in all age groups when performing bowel preparation.

Background/Aims: Utilization of low-volume preparation agents is crucial to improve patient willingness to undergo repeat colonoscopies. However, gastric safety data on preparation agents are limited. This study evaluated the acute gastropathy associated with bowel preparation agents. Methods: This retrospective study enrolled healthy subjects who underwent both esophagogastroduodenoscopy and colonoscopy screening. Baseline patient characteristics, bowel preparation success, acute gastropathy, and polyp and adenoma detection rates were evaluated for 1 L polyethylene glycol with ascorbic acid (1 L PEG/Asc) and oral sulfate tablet (OST) groups. Results: Comparison of the OST group (n=2,463) with the 1 L PEG/Asc group (n=2,060) revealed that the rates of successful cleansing and high-quality cleansing were similar between the two groups. Polyp and adenoma detection rates were significantly higher in the OST group than in the 1 L PEG/Asc group (p<0.001 and p=0.013), while the incidence of acute gastric mucosal lesion-like blood stain/clot, erosions at greater curvature side of antrum/body, multiple erosions, and overlying mucosal erythema or edema were all significantly higher in the OST group than in the 1 L PEG/Asc group (all p<0.001). Additionally, high and indeterminate probability scores of preparation agent-induced gastropathy (p=0.001) and mean Lanza scores were significantly higher in the OST group than in the 1 L PEG/Asc group (1.3 vs. 0.4, p<0.001). Conclusions Compared with 1 L PEG/Asc, OSTs were significantly associated with acute gastropathy during bowel preparation, thus requiring careful consideration from physicians for the simultaneous screening of EGD and colonoscopy.