Purpose: Radiotherapy (RT) remains a cornerstone of curative treatment for localized and locally advanced prostate cancer. However, dose escalation to improve tumor control is often constrained by the proximity of the rectum, which increases the risk of gastrointestinal (GI) and genitourinary toxicities. Biodegradable rectal spacers inserted between the prostate and rectum have emerged as an effective approach to reduce rectal radiation exposure. This guideline provides evidence-based recommendations on indications, contraindications, procedural standards, and clinical management for biodegradable rectal spacer insertion during prostate cancer RT. Materials and Methods: This guideline was developed by a multidisciplinary expert panel through a systematic review of the literature, analysis of international guidelines (National Comprehensive Cancer Network, European Association of Urology, American Society for Radiation Oncology), and expert consensus among radiation oncologists, radiologists, and urologists with clinical experience in spacer insertion. The strength of each recommendation and the level of evidence were classified according to the modified GRADE (Grading of Recommendations, Assessment, Development, and Evaluation) system. Results: Spacer insertion is conditionally recommended (Grade C, Level I) for patients receiving definitive external-beam RT without rectal invasion. It reduces the high-dose rectal irradiation volume (V70–75) by >50%, decreases acute GI toxicity, and helps maintain bowel-related quality of life. However, the benefit for late severe toxicity (grade 2 or higher) remains debated in recent meta-analyses. Contraindications include rectal invasion, anatomical inaccessibility, infection, and material hypersensitivity. Procedures should be performed under local anesthesia in a sterile environment by trained physicians. Short-course antibiotics and simulator-based training, including completion of multiple supervised cases, are advised. Conclusion Biodegradable rectal spacer insertion is clinically validated and effective in reducing acute rectal toxicity. Although pivotal trials demonstrated a favorable procedural safety profile, real-world postmarket data include reports of rare but severe procedural complications. This guideline provides standardized recommendations tailored to Korean clinical practice while remaining consistent with international standards, emphasizing the importance of operator training and careful patient selection.

Anomalous union of the pancreaticobiliary duct (AUPBD) is a congenital malformation in which the pancreatic and biliary ducts join outside the duodenal wall, forming an elongated common channel. Because sphincter action does not directly affect this junction, reciprocal reflux of pancreatic juice and bile occurs, increasing the risk of biliary tract cancer. AUPBD is frequently associated with choledochal cysts and is a known risk factor for biliary malignancies. We report a case of a 70-year-old woman diagnosed with gallbladder cancer with liver metastases, accompanied by AUPBD without choledochal cysts. She presented with upper abdominal pain, obstructive jaundice, and a large hepatic mass on imaging. Endoscopic retrograde cholangiopancreatography confirmed pancreatobiliary-type AUPBD. Despite biliary drainage, her condition rapidly deteriorated and she died soon after. This case underscores the role of AUPBD in carcinogenesis and the need for early recognition and management.

Background: Acute bronchiolitis is a common cause of hospitalization during infancy that carries significant morbidity and mortality rates.Purpose: This study compared the efficacy of different treatment modalities for infants with bronchiolitis in terms of hospital stay and clinical severity scores. Methods: The PubMed database was searched for relevant studies. Eligibility criteria included double-blind randomized controlled trial design, assessment of the effect of treatment on bronchiolitis in infants under 2 years of age, and publication in English from inception through July 31, 2020. The primary efficacy outcome was the length of hospital stay, while the secondary outcome was the clinical severity score. The standardized treatment effect and standard error of the effect size were calculated. Results: We identified 45 randomized controlled trials of 24 pairwise comparisons. These 45 trials included 5,061 participants and investigated 13 types of interventions (12 active, 1 placebo). Inhalation therapy with epinephrine (standard mean difference [SMD], -0.41; 95% confidence interval [CI], -0.8 to -0.03) and hypertonic saline (SMD, -0.29; 95% CI, -0.55 to -0.03) reduced the length of hospital stay compared with normal saline. Hypertonic saline was the most effective at improving the clinical severity score (SMD, -0.52; 95% CI, -0.95 to -0.10). Conclusion Inhalation therapy with epinephrine and hypertonic saline reduced the length of hospital stay and the clinical severity of bronchiolitis among infants under 2 years of age.

Background: Acute bronchiolitis is a common cause of hospitalization during infancy that carries significant morbidity and mortality rates.Purpose: This study compared the efficacy of different treatment modalities for infants with bronchiolitis in terms of hospital stay and clinical severity scores. Methods: The PubMed database was searched for relevant studies. Eligibility criteria included double-blind randomized controlled trial design, assessment of the effect of treatment on bronchiolitis in infants under 2 years of age, and publication in English from inception through July 31, 2020. The primary efficacy outcome was the length of hospital stay, while the secondary outcome was the clinical severity score. The standardized treatment effect and standard error of the effect size were calculated. Results: We identified 45 randomized controlled trials of 24 pairwise comparisons. These 45 trials included 5,061 participants and investigated 13 types of interventions (12 active, 1 placebo). Inhalation therapy with epinephrine (standard mean difference [SMD], -0.41; 95% confidence interval [CI], -0.8 to -0.03) and hypertonic saline (SMD, -0.29; 95% CI, -0.55 to -0.03) reduced the length of hospital stay compared with normal saline. Hypertonic saline was the most effective at improving the clinical severity score (SMD, -0.52; 95% CI, -0.95 to -0.10). Conclusion Inhalation therapy with epinephrine and hypertonic saline reduced the length of hospital stay and the clinical severity of bronchiolitis among infants under 2 years of age.

Background: Acute bronchiolitis is a common cause of hospitalization during infancy that carries significant morbidity and mortality rates.Purpose: This study compared the efficacy of different treatment modalities for infants with bronchiolitis in terms of hospital stay and clinical severity scores. Methods: The PubMed database was searched for relevant studies. Eligibility criteria included double-blind randomized controlled trial design, assessment of the effect of treatment on bronchiolitis in infants under 2 years of age, and publication in English from inception through July 31, 2020. The primary efficacy outcome was the length of hospital stay, while the secondary outcome was the clinical severity score. The standardized treatment effect and standard error of the effect size were calculated. Results: We identified 45 randomized controlled trials of 24 pairwise comparisons. These 45 trials included 5,061 participants and investigated 13 types of interventions (12 active, 1 placebo). Inhalation therapy with epinephrine (standard mean difference [SMD], -0.41; 95% confidence interval [CI], -0.8 to -0.03) and hypertonic saline (SMD, -0.29; 95% CI, -0.55 to -0.03) reduced the length of hospital stay compared with normal saline. Hypertonic saline was the most effective at improving the clinical severity score (SMD, -0.52; 95% CI, -0.95 to -0.10). Conclusion Inhalation therapy with epinephrine and hypertonic saline reduced the length of hospital stay and the clinical severity of bronchiolitis among infants under 2 years of age.

Background: Acute bronchiolitis is a common cause of hospitalization during infancy that carries significant morbidity and mortality rates.Purpose: This study compared the efficacy of different treatment modalities for infants with bronchiolitis in terms of hospital stay and clinical severity scores. Methods: The PubMed database was searched for relevant studies. Eligibility criteria included double-blind randomized controlled trial design, assessment of the effect of treatment on bronchiolitis in infants under 2 years of age, and publication in English from inception through July 31, 2020. The primary efficacy outcome was the length of hospital stay, while the secondary outcome was the clinical severity score. The standardized treatment effect and standard error of the effect size were calculated. Results: We identified 45 randomized controlled trials of 24 pairwise comparisons. These 45 trials included 5,061 participants and investigated 13 types of interventions (12 active, 1 placebo). Inhalation therapy with epinephrine (standard mean difference [SMD], -0.41; 95% confidence interval [CI], -0.8 to -0.03) and hypertonic saline (SMD, -0.29; 95% CI, -0.55 to -0.03) reduced the length of hospital stay compared with normal saline. Hypertonic saline was the most effective at improving the clinical severity score (SMD, -0.52; 95% CI, -0.95 to -0.10). Conclusion Inhalation therapy with epinephrine and hypertonic saline reduced the length of hospital stay and the clinical severity of bronchiolitis among infants under 2 years of age.

Purpose: To assess the prevalence of food allergy, with a focus on oral allergy syndrome (OAS) in a population of children and to investigate relevant allergen sensitization associated with these adverse reactions. Methods: This study involved 1,660 children (aged 4 to 13 years) experiencing seasonal allergy symptoms, who were enrolled in the 2015 prospective Seongnam Atopy Project (SAP 2015) in a South Korean municipality. Parents completed a structured questionnaire to assess children with OAS, collecting information on the duration, severity, and factors related to symptoms. Skin prick tests (n = 498) and blood sampling (n= 464) were performed to measure allergic sensitizations, total eosinophil counts, and levels both total immunoglobulin E (IgE) and birch-specific IgE. Results: The prevalence of OAS among the children enrolled in this study was 4.4% (95% confidence interval, 3.7%–5.1%). The most common symptom was mouth itching (n= 106, 65.0%), and the primary food allergen associated with symptoms was kiwi (n= 48, 29.5%). Peanut sensitization (14.8% vs. 57.1%, P< 0.001) and sensitization to other nut products (15.6% vs. 47.6%, P= 0.001) were linked to a higher incidence of systemic reactions. Conclusion The prevalence of 4.4% underscores the significant health impact of OAS, especially in children experiencing food allergy-related symptoms. Notably, common allergens, such as kiwi, and the potential for additional systemic reactions associated with this condition highlight the importance of raising awareness.

Allergen immunotherapy (AIT) has been used for over a century and has been demonstrated to be effective in treating patients with various allergic diseases. AIT allergens can be administered through various routes, including subcutaneous, sublingual, intralymphatic, oral, or epicutaneous routes. Sublingual immunotherapy (SLIT) has recently gained clinical interest, and it is considered an alternative treatment for allergic rhinitis (AR) and asthma. This review provides an overview of the current evidence-based studies that address the use of SLIT for treating AR, including (1) mechanisms of action, (2) appropriate patient selection for SLIT, (3) the current available SLIT products in Korea, and (4) updated information on its efficacy and safety. Finally, this guideline aims to provide the clinician with practical considerations for SLIT.