Incidentally detected gallbladder polyps (GBPs) and gallbladder wall thickening (GBWT) are frequently encountered in clinical practice. However, characterizing GBPs and GBWT in asymptomatic patients can be challenging and may result in overtreatment, including unnecessary follow-ups or surgeries. The Korean Society of Abdominal Radiology (KSAR) Clinical Practice Guideline Committee has developed expert recommendations that focus on standardized imaging interpretation and follow-up strategies for both GBPs and GBWT, with support from the Korean Society of Radiology and KSAR. These guidelines, which address 24 key questions, aim to standardize the approach for the interpretation of imaging findings, reporting, imaging-based workups, and surveillance of incidentally detected GBPs and GBWT. This recommendation promotes evidence-based practice, facilitates communication between radiologists and referring physicians, and reduces unnecessary interventions.

Background/Aims: Although gastrointestinal endoscopy (GIE) is a major contributor to the carbon footprint of national healthcare, the amount of medical waste generated by GIE procedures is not reported in South Korea. This study aimed to measure the amount of medical waste generated from GIE procedures in South Korea. Methods: We conducted a 5-day audit of medical waste generated during GIEs at seven hospitals. During the study period, medical waste in the endoscopy examination rooms was measured twice daily and documented as mass (kg). To calculate the mean mass of disposable waste generated during one esophagogastroduodenoscopy (EGD) and one colonoscopy, the mean mass of medical waste generated from seven examinations was calculated. The mean mass of medical waste generated during GIEs was calculated by dividing the total mass of medical waste generated by the number of GIE procedures. Results: Overall, 3,922 endoscopies were performed and 4,558 kg of waste was generated. The mean weight of medical waste generated per endoscopy was 1.34 kg. Each EGD and colonoscopy generated a mean of 0.24 kg and 0.43 kg of disposable waste, respectively. Applying the mean waste estimates from this study to annual GIE procedures performed in South Korea in 2022 showed that the total medical waste produced from GIE was 13,704,453 kg. In addition, the total masses of medical waste produced during EGD and colonoscopy procedures were 819,766 kg and 2,889,478 kg, respectively. Conclusions Our quantitative measurement showed that a large amount of medical waste is generated from GIE procedures. However, further research is warranted to reduce medical waste generated during GIE, which is an urgent unmet need.

Progesterone hypersensitivity is mediated by type I, III, and IV hypersensitivity reactions to endogenous or exogenous progesterone, involving autoimmune mechanisms in females of reproductive age. It presents with a range of dermatologic manifestations, most commonly urticaria, angioedema, eczema, and maculopapular rashes. Systemic and severe symptoms, such as generalized erythema multiforme or lesions resembling severe cutaneous adverse reactions, have rarely been reported. We describe a case of a 42-year-old woman who developed drug reaction with eosinophilia and systemic symptoms (DRESS) following exogenous progesterone therapy administered for assisted reproduction. She received high-dose subcutaneous progesterone and vaginal tablets. Despite this being her first procedure, she achieved pregnancy. However, at 8 weeks of gestation and during the third month of progesterone treatment, she developed generalized erythema multiforme, pruritus, and high-grade fever. Her laboratory findings showed increased blood eosinophil counts and inflammatory markers. After oral corticosteroid (OCS) treatment for several weeks, her skin lesions were partially improved. However, after tapering of OCS, her skin lesions were aggravated with increased blood eosinophil counts. Despite daily OCS (prednisolone, 12.5–60 mg/day) treatment after childbirth, her skin symptoms and eosinophilia persisted. Reslizumab treatment was also attempted, but only the eosinophilia resolved. These clinical findings were much improved after Janus kinase (JAK) inhibitor (upadacitinib 15 mg/day) treatment; consequently, OCS was stopped. Here, we report a case of relapsing DRESS triggered by exogenous progesterone, which has been controlled by JAK inhibitor treatment.

Cat-pork syndrome is an uncommon food allergy induced by red meat (pork/beef) that cross-reacts with cat/dog allergens, which is mediated by immunoglobulin E (IgE) response to the cat/dog albumin component. We report 2 cases of cat-pork syndrome occurred in adult pet breeders. They had suffered from allergic rhinitis/atopic dermatitis sensitive to cat/dog dander as well as house dust mites for several years, during which an immediate type of food allergy due to red meats developed whenever taking pork or beef. ImmunoCAP results showed the increased levels of serum-specific IgE to pork and beef allergens (f26, f27) as well as cat and dog dander (e1, e5); moreover, increased level of serum-specific IgE to the cat albumin component (e224) was noted. In conclusion, cat-food allergy can be found in allergic patients among whom are sensitive to cats and dogs and develop food allergy due to red meat.

Progesterone hypersensitivity is mediated by type I, III, and IV hypersensitivity reactions to endogenous or exogenous progesterone, involving autoimmune mechanisms in females of reproductive age. It presents with a range of dermatologic manifestations, most commonly urticaria, angioedema, eczema, and maculopapular rashes. Systemic and severe symptoms, such as generalized erythema multiforme or lesions resembling severe cutaneous adverse reactions, have rarely been reported. We describe a case of a 42-year-old woman who developed drug reaction with eosinophilia and systemic symptoms (DRESS) following exogenous progesterone therapy administered for assisted reproduction. She received high-dose subcutaneous progesterone and vaginal tablets. Despite this being her first procedure, she achieved pregnancy. However, at 8 weeks of gestation and during the third month of progesterone treatment, she developed generalized erythema multiforme, pruritus, and high-grade fever. Her laboratory findings showed increased blood eosinophil counts and inflammatory markers. After oral corticosteroid (OCS) treatment for several weeks, her skin lesions were partially improved. However, after tapering of OCS, her skin lesions were aggravated with increased blood eosinophil counts. Despite daily OCS (prednisolone, 12.5–60 mg/day) treatment after childbirth, her skin symptoms and eosinophilia persisted. Reslizumab treatment was also attempted, but only the eosinophilia resolved. These clinical findings were much improved after Janus kinase (JAK) inhibitor (upadacitinib 15 mg/day) treatment; consequently, OCS was stopped. Here, we report a case of relapsing DRESS triggered by exogenous progesterone, which has been controlled by JAK inhibitor treatment.

Cat-pork syndrome is an uncommon food allergy induced by red meat (pork/beef) that cross-reacts with cat/dog allergens, which is mediated by immunoglobulin E (IgE) response to the cat/dog albumin component. We report 2 cases of cat-pork syndrome occurred in adult pet breeders. They had suffered from allergic rhinitis/atopic dermatitis sensitive to cat/dog dander as well as house dust mites for several years, during which an immediate type of food allergy due to red meats developed whenever taking pork or beef. ImmunoCAP results showed the increased levels of serum-specific IgE to pork and beef allergens (f26, f27) as well as cat and dog dander (e1, e5); moreover, increased level of serum-specific IgE to the cat albumin component (e224) was noted. In conclusion, cat-food allergy can be found in allergic patients among whom are sensitive to cats and dogs and develop food allergy due to red meat.

Purpose: It is well known that the majority of the extranodal marginal zone lymphomas of mucosa-associated lymphoid tissues (MALT lymphomas) are associated with microbiota, e.g., gastric MALT lymphoma with Helicobacter pylori. In general, they are very sensitive to low-dose radiotherapy and chemotherapeutic agents. The microbiota profile is not clearly elucidated in bronchus-associated lymphoid tissue (BALT) lymphoma, a rare type of MALT lymphoma in the lung. Thus, this study aimed to clarify the intratumor microbiome in BALT lymphoma using the third-generation next-generation sequencing (NGS) method. Materials and Methods: DNAs were extracted from 12 formalin-fixed paraffin-embedded (FFPE) tumor tissues obtained from BALT lymphoma patients diagnosed between 1990 and 2016. 16S rRNA gene was amplified by polymerase chain reaction. Amplicons were sequenced using a Nanopore platform. Next-generation sequencing analysis was performed to assess microbial profiles. For comparison, FFPE specimens from nine non-cancerous lung tissues were also analyzed. Results: Specific bacterial families including Burkholderiaceae, Bacillaceae, and Microbacteriaceae were associated with BALT lymphoma by a linear discriminant analysis effect size approach. Although the number of specimens was limited, BALT lymphomas exhibited significantly higher microbial abundance and diversity with distinct microbial composition patterns and correlation networks than non-cancerous lung tissues. Conclusion This study provides the first insight into intratumor microbiome in BALT lymphoma using the third-generation NGS method. A distinct microbial composition suggests the presence of a unique tumor microenvironment of BALT lymphoma.

Purpose: Recent development in perioperative treatment of resectable non–small cell lung cancer (NSCLC) have changed the landscape of early lung cancer management. The ADAURA trial has demonstrated the efficacy of adjuvant osimertinib treatment in resectable NSCLC patients; however, studies are required to show which subgroup of patients are at a high risk of relapse and require adjuvant epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor treatment. This study evaluated risk factors for postoperative relapse among patients who underwent complete resection. Materials and Methods: Data were obtained from the Korean Association for Lung Cancer Registry (KALC-R), a database created using a retrospective sampling survey by the Korean Central Cancer Registry (KCCR) and the Lung Cancer Registration Committee. Results: A total of 3,176 patients who underwent curative resection was evaluated. The mean observation time was approximately 35.4 months. Among stage I to IIIA NSCLC patients, the EGFR-mutant subgroup included 867 patients, and 75.2%, 11.2%, and 11.8% were classified as stage I, stage II, and stage III, respectively. Within the EGFR-mutant subgroup, 44 (5.1%) and 121 (14.0%) patients showed early and late recurrence, respectively. Multivariate analysis on association with postoperative relapse among the EGFR-mutant subgroup showed that age, pathologic N and TNM stages, pleural invasion status, and surgery type were independent significant factors. Conclusion Among the population that underwent complete resection for early NSCLC with EGFR mutation, patients with advanced stage, pleural invasion, or limited resection are more likely to show postoperative relapse.

Background/Aims: Although gastrointestinal endoscopy (GIE) is a major contributor to the carbon footprint of national healthcare, the amount of medical waste generated by GIE procedures is not reported in South Korea. This study aimed to measure the amount of medical waste generated from GIE procedures in South Korea. Methods: We conducted a 5-day audit of medical waste generated during GIEs at seven hospitals. During the study period, medical waste in the endoscopy examination rooms was measured twice daily and documented as mass (kg). To calculate the mean mass of disposable waste generated during one esophagogastroduodenoscopy (EGD) and one colonoscopy, the mean mass of medical waste generated from seven examinations was calculated. The mean mass of medical waste generated during GIEs was calculated by dividing the total mass of medical waste generated by the number of GIE procedures. Results: Overall, 3,922 endoscopies were performed and 4,558 kg of waste was generated. The mean weight of medical waste generated per endoscopy was 1.34 kg. Each EGD and colonoscopy generated a mean of 0.24 kg and 0.43 kg of disposable waste, respectively. Applying the mean waste estimates from this study to annual GIE procedures performed in South Korea in 2022 showed that the total medical waste produced from GIE was 13,704,453 kg. In addition, the total masses of medical waste produced during EGD and colonoscopy procedures were 819,766 kg and 2,889,478 kg, respectively. Conclusions Our quantitative measurement showed that a large amount of medical waste is generated from GIE procedures. However, further research is warranted to reduce medical waste generated during GIE, which is an urgent unmet need.

Background/Aims: The Korean guidelines for Helicobacter pylori treatment were revised in 2020, however, the extent of adherence to these guidelines in clinical practice remains unclear. Herein, we initiated a prospective, nationwide, multicenter registry study in 2021 to evaluate the current management of H.pylori infection in Korea. Methods: This interim report describes the adherence to the revised guidelines and their impact on firstline eradication rates. Data on patient demographics, diagnoses, treatments, and eradication outcomes were collected using a web-based electronic case report form. Results: A total of 7,261 patients from 66 hospitals who received first-line treatment were analyzed.The modified intention-to-treat eradication rate for first-line treatment was 81.0%, with 80.4% of the prescriptions adhering to the revised guidelines. The most commonly prescribed regimen was the 14-day clarithromycin-based triple therapy (CTT; 42.0%), followed by tailored therapy (TT; 21.2%), 7-day CTT (14.1%), and 10-day concomitant therapy (CT; 10.1%). Time-trend analysis demonstrated significant increases in guideline adherence and the use of 10-day CT and TT, along with a decrease in the use of 7-day CTT (all p<0.001). Multivariate logistic regression analysis revealed that guideline adherence was significantly associated with first-line eradication success (odds ratio, 2.03; 95% confidence interval, 1.61 to 2.56; p<0.001). Conclusions The revised guidelines for the treatment of H. pylori infection have been increasingly adopted in routine clinical practice in Korea, which may have contributed to improved first-line eradication rates. Notably, the 14-day CTT, 10-day CT, and TT regimens are emerging as the preferred first-line treatment options among Korean physicians.