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: Rosacea is a chronic inflammatory skin disorder characterized by erythema, papules, ocular symptoms, and heightened sensitivity. Patients with neurogenic symptoms such as burning or stinging remain particularly difficult to manage. Current guidelines often underrepresent energy-based devices (EBDs), pigmentary sequelae, psychosocial burden, and ocular comorbidities. Objective: To examine Korean dermatologists’ expert perspectives on rosacea management, focusing on skin sensitivity, neurogenic symptoms, pigmentary changes, psychosocial impact, ocular involvement, and EBD use. Methods: A web-based, 29-item survey was administered to 25 board-certified Korean dermatologists (May–June 2025). Quantitative and qualitative responses were analyzed. Results: Erythematotelangiectatic and papulopustular phenotypes with sensitivity skin predominated. EBDs (pulsed dye laser, intense pulsed light) were frequently used but limited by cost and sensitivity issues. Neurogenic symptoms were recognized but rarely treated with neuromodulators. Post-inflammatory hyperpigmentation was infrequent, yet monitoring was inconsistent.Psychosocial and ocular aspects were acknowledged but seldomly systematically addressed.Respondents expressed interest in emerging adjunctive treatments such as cold plasma, skin boosters, and holistic care approaches. Conclusion Korean dermatologists adopt individualized strategies for rosacea, yet practice gaps remain regarding neurogenic symptoms, pigmentary complications, and psychosocial and ocular comorbidities. Findings support the need for updated multidisciplinary, phenotype-driven guidelines aligned with real-world practice.

Vaccine-induced hypermetabolic lymph nodes have been clinically observed following coronavirus disease 2019 (COVID-19) mRNA vaccination. Specifically, the booster dose of the mRNA vaccines, produced by Pfizer and Moderna, has been linked to a relatively high incidence of lymphadenopathy. We present the case of a kidney transplant recipient who developed an enlarged abdominal mass after receiving a booster dose of the COVID-19 mRNA vaccine. This mass occupied the retroperitoneal space, infiltrated the psoas muscle, and resulted in ureteric compression and hydronephrosis. Percutaneous drainage and analysis of the perirenal fluid revealed the presence of lymphatic fluid. In summary, lymphadenopathy is a recognized adverse reaction to the Pfizer and Moderna vaccines. Patients with compromised immune systems should be informed about the incidence and potential severity of lymphadenopathy following booster vaccination.

Vaccine-induced hypermetabolic lymph nodes have been clinically observed following coronavirus disease 2019 (COVID-19) mRNA vaccination. Specifically, the booster dose of the mRNA vaccines, produced by Pfizer and Moderna, has been linked to a relatively high incidence of lymphadenopathy. We present the case of a kidney transplant recipient who developed an enlarged abdominal mass after receiving a booster dose of the COVID-19 mRNA vaccine. This mass occupied the retroperitoneal space, infiltrated the psoas muscle, and resulted in ureteric compression and hydronephrosis. Percutaneous drainage and analysis of the perirenal fluid revealed the presence of lymphatic fluid. In summary, lymphadenopathy is a recognized adverse reaction to the Pfizer and Moderna vaccines. Patients with compromised immune systems should be informed about the incidence and potential severity of lymphadenopathy following booster vaccination.

Vaccine-induced hypermetabolic lymph nodes have been clinically observed following coronavirus disease 2019 (COVID-19) mRNA vaccination. Specifically, the booster dose of the mRNA vaccines, produced by Pfizer and Moderna, has been linked to a relatively high incidence of lymphadenopathy. We present the case of a kidney transplant recipient who developed an enlarged abdominal mass after receiving a booster dose of the COVID-19 mRNA vaccine. This mass occupied the retroperitoneal space, infiltrated the psoas muscle, and resulted in ureteric compression and hydronephrosis. Percutaneous drainage and analysis of the perirenal fluid revealed the presence of lymphatic fluid. In summary, lymphadenopathy is a recognized adverse reaction to the Pfizer and Moderna vaccines. Patients with compromised immune systems should be informed about the incidence and potential severity of lymphadenopathy following booster vaccination.

Vaccine-induced hypermetabolic lymph nodes have been clinically observed following coronavirus disease 2019 (COVID-19) mRNA vaccination. Specifically, the booster dose of the mRNA vaccines, produced by Pfizer and Moderna, has been linked to a relatively high incidence of lymphadenopathy. We present the case of a kidney transplant recipient who developed an enlarged abdominal mass after receiving a booster dose of the COVID-19 mRNA vaccine. This mass occupied the retroperitoneal space, infiltrated the psoas muscle, and resulted in ureteric compression and hydronephrosis. Percutaneous drainage and analysis of the perirenal fluid revealed the presence of lymphatic fluid. In summary, lymphadenopathy is a recognized adverse reaction to the Pfizer and Moderna vaccines. Patients with compromised immune systems should be informed about the incidence and potential severity of lymphadenopathy following booster vaccination.

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.

Allergen immunotherapy (AIT) is a causative treatment of allergic diseases in which allergen extracts are regularly administered in a gradually escalated doses, leading to immune tolerance and consequent alleviation of allergic diseases. The need for uniform practice guidelines in AIT is continuously growing as the number of potential candidates for AIT increases and new therapeutic approaches are tried. This updated version of the Korean Academy of Asthma Allergy and Clinical Immunology recommendations for AIT, published in 2010, proposes an expert opinion by specialists in allergy, pediatrics, and otorhinolaryngology. This guideline deals with the basic knowledge of AIT, including mechanisms, clinical efficacy, allergen standardization, important allergens in Korea, and special consideration in pediatrics. The article also covers the methodological aspects of AIT, including patient selection, allergen selection, schedule and doses, follow-up care, efficacy measurements, and management of adverse reactions. Although this guideline suggests the optimal dosing schedule, an individualized approach and modifications are recommended considering the situation for each patient and clinic.

These guidelines aim to establish the standard practice for diagnosing and treating patients with differentiated thyroid cancer (DTC). Based on the Korean Thyroid Association (KTA) Guidelines on DTC management, the “Treatment of Advanced DTC” section was revised in 2024 and has been provided through this chapter. Especially, this chapter covers surgical and nonsurgical treatments for the local (previous surgery site) or regional (cervical lymph node metastasis) recurrences. After drafting the guidelines, it was finalized by collecting opinions from KTA members and related societies. Surgical resection is the preferred treatment for local or regional recurrence of advanced DTC. If surgical resection is not possible, nonsurgical resection treatment under ultrasonography guidance may be considered as an alternative treatment for local or regional recurrence of DTC. Furthermore, if residual lesions are suspected even after surgical resection or respiratory-digestive organ invasion, additional radioactive iodine and external radiation treatments are considered.

Pediatric differentiated thyroid cancers (DTCs), mostly papillary thyroid cancer (PTC, 80-90%), are diagnosed at more advanced stages with larger tumor sizes and higher rates of locoregional and/or lung metastasis. Despite the higher recurrence rates of pediatric cancers than of adult thyroid cancers, pediatric patients demonstrate a lower mortality rate and more favorable prognosis. Considering the more advanced stage at diagnosis in pediatric patients, preoperative evaluation is crucial to determine the extent of surgery required. Furthermore, if hereditary tumor syndrome is suspected, genetic testing is required. Recommendations for pediatric DTCs focus on the surgical principles, radioiodine therapy according to the postoperative risk level, treatment and follow-up of recurrent or persistent diseases, and treatment of patients with radioiodine-refractory PTCs on the basis of genetic drivers that are unique to pediatric patients.