In patients with differentiated thyroid cancer (DTC), initial recurrence risk stratification based on clinical, histopathological, and perioperative data remains the key determinant for guiding management strategies during the first 1-2 years post-treatment. However, the adoption of ongoing risk stratification (ORS), which dynamically reassesses risk by integrating longitudinal clinical data and treatment response, enables more precise long-term prognostic assessment and facilitates highly individualized management. Building upon recent guidelines, the 2026 KTA guideline has been further refined by incorporating robust evidence from large-scale national cohorts and comprehensive systematic reviews. These updated recommendations outline contemporary concepts of ORS, risk-adapted TSH suppression targets, optimized surveillance modalities for recurrence detection, and disease-specific long-term follow-up strategies. Reflecting the paradigm shift toward de-escalated treatment, this revision integrates evolved perspectives on TSH suppression intensity, the clinical interpretation of thyroglobulin levels, and tailored follow-up intervals. These evidence-based recommendations aim to minimize unnecessary treatment and excessive surveillance in the large proportion of patients with excellent prognosis after initial therapy, while ensuring that each patient receives appropriately tailored and effective long-term management.

The increasing detection of papillary thyroid microcarcinoma (PTMC) has raised concerns about overtreatment.For low-risk PTMC, either immediate surgery or active surveillance (AS) can be considered. To support AS implementation, the Korean Thyroid Association convened a multidisciplinary panel and developed the first Korean guideline. AS is recommended to adults with pathologically proven Bethesda V-VI PTMC without clinical evidence of lymph node or distant metastasis, gross extrathyroidal extension, tracheal or recurrent laryngeal nerve invasion, or aggressive histology. Baseline assessment requires high‑resolution cervical ultrasound by experienced operators to rule out extrathyroidal extension, tracheal or recurrent laryngeal nerve invasion, and lymph node metastasis;contrast‑enhanced neck computed tomography is optional. Patient characteristics such as age, comorbidities, and capacity for long-term follow-up should be assessed. Shared decision-making should weigh the benefits and risks of surgery and AS, expected oncologic outcomes, complications, quality of life, anxiety, medical cost, and patient preference. Follow-up includes cervical ultrasound and thyroid function test every six months for two years, then annually. Disease progression, defined as significant tumor growth or newly detected nodal or distant metastasis, warrants surgery. Despite remaining uncertainties, this guideline offers a framework to ensure oncologic safety and support patient-centered active surveillance.

Purpose: In this study, we evaluated 66 patients diagnosed with adenoid cystic carcinoma (ACC) enrolled in two Korean Cancer Study Group trials to investigate the response and progression patterns in recurrent and/or metastatic ACC treated with vascular endothelial growth factor receptor tyrosine kinase inhibitors (VEGFR-TKIs). Materials and Methods: We evaluated 66 patients diagnosed with ACC who were enrolled in the Korean Cancer Study Group trials. The tumor measurements, clinical data, treatment outcomes, and progression patterns of therapy were analyzed. Results: In the 66 patients (53 receiving axitinib and 13 receiving nintedanib), the disease control rate was 61%, and three patients achieved partial response. The median follow-up, median progression-free survival (PFS), overall survival, and 6-month PFS rate were 27.6%, 12.4%, and 18.1% months and 62.1%, respectively. Among 42 patients who experienced progression, 27 (64.3%) showed target lesion progression. Bone metastasis was an independent poor prognostic factor. Conclusion Overall, most patients demonstrated stable disease with prolonged PFS; however, prominent target lesion progression occurred in some patients. Thus, PFS may capture VEGFR-TKI efficacy better than the objective response rate.

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.

Differentiated thyroid cancer demonstrates a wide range of clinical presentations, from very indolent cases to those with an aggressive prognosis. Therefore, diagnosing and treating each cancer appropriately based on its risk status is important. The Korean Thyroid Association (KTA) has provided and amended the clinical guidelines for thyroid cancer management since 2007. The main changes in this revised 2024 guideline include 1) individualization of surgical extent according to pathological tests and clinical findings, 2) application of active surveillance in low-risk papillary thyroid microcarcinoma, 3) indications for minimally invasive surgery, 4) adoption of World Health Organization pathological diagnostic criteria and definition of terminology in Korean, 5) update on literature evidence of recurrence risk for initial risk stratification, 6) addition of the role of molecular testing, 7) addition of definition of initial risk stratification and targeting thyroid stimulating hormone (TSH) concentrations according to ongoing risk stratification (ORS), 8) addition of treatment of perioperative hypoparathyroidism, 9) update on systemic chemotherapy, and 10) addition of treatment for pediatric patients with thyroid cancer.

Background/Aims: Tuberculosis has incidence and mortality rates that are among the highest for all communicable diseases. Adverse drug reactions (ADRs) to anti-tubercular drugs are common, and have a major impact on treatment maintenance and prognosis. It is important to understand the characteristics of ADRs and establish a suitable management plan. Methods: We retrospectively reviewed patients with ADRs during treatment with first-line antitubercular drugs such as isoniazid, rifampicin, ethambutol, and pyrazinamide from 2009 to 2018. Age, sex, and total treatment period, and the onset, severity, seriousness, and system organ class of ADRs, were analyzed to understand the characteristics of first-line anti-tubercular drug-related ADRs. Results: A total of 1,606 of 5,482 patients (29.3%) experienced ADRs after administration of first-line anti-tubercular drugs. The incidence of ADRs related to isoniazid, rifampicin, ethambutol, and pyrazinamide was 22.2%, 21.3%, 24.5%, and 29.6%, respectively. A total of 2,098 ADR reports were made (mean of 1.3 ± 0.6 per patient). The rates of mild, moderate, and severe ADRs were 32.4%, 61.1%, and 6.5%, respectively. There were 127 reports (6.1%) of serious ADRs. Skin and appendage disorders were most frequently reported (27.5%), followed by gastrointestinal disorders (17.5%), and liver and biliary system disorders (13.1%). The total treatment period was longer in patients who experienced ADRs (224.0 ± 3.1 days vs. 247.0 ± 4.7 days, p = 0.009). Conclusions The incidence of ADRs to first-line anti-tuberculosis drugs was 29.3%, and 6.5% were severe ADRS. ADRs prolonged the overall treatment duration, indicating the importance of their detection and management.

Background/Aims: Despite proper use of pharmaceuticals, adverse drug reactions (ADRs) can lead to problems related to patient safety. We analyzed the characteristics of ADRs, particularly serious adverse events (SAEs), in a single tertiary medical institution. Methods: Spontaneous ADR report data collected from 2010 to 2019 in Seoul National University Hospital were assessed. Causality was evaluated according to the World Health Organization-Uppsala Monitoring Centre criteria. Age, sex, onset, severity, seriousness, and system organ class (SOC) of ADRs and SAEs were analyzed. Results: During the study period, a total of 49,955 individual case safety reports were assessed as possible, probable, or certain. Although the number of gastrointestinal ADR reports was high (25.9%), severe cases were uncommon (2.6%). By contrast, the number of hematologic disorders was low (6.6%) but 39.2% of them were severe. Among ADRs, 10.2% were assessed as SAEs, the proportion of which was high at extreme ages and in males. Body as a whole-general disorders were the most frequently reported SOC for SAEs, followed by skin and appendage disorders. Antineoplastic agents and antibiotics were the most common causative agents of SAEs and ADRs. Anaphylactic reaction was the most frequent SAE (6.5%). Conclusions The proportion of SAE differs according to SOC and drug. Attention should be paid to SAEs in children and older adults because the rate of SAEs is significantly higher at extreme ages.

Background/Aims: Despite proper use of pharmaceuticals, adverse drug reactions (ADRs) can lead to problems related to patient safety. We analyzed the characteristics of ADRs, particularly serious adverse events (SAEs), in a single tertiary medical institution. Methods: Spontaneous ADR report data collected from 2010 to 2019 in Seoul National University Hospital were assessed. Causality was evaluated according to the World Health Organization-Uppsala Monitoring Centre criteria. Age, sex, onset, severity, seriousness, and system organ class (SOC) of ADRs and SAEs were analyzed. Results: During the study period, a total of 49,955 individual case safety reports were assessed as possible, probable, or certain. Although the number of gastrointestinal ADR reports was high (25.9%), severe cases were uncommon (2.6%). By contrast, the number of hematologic disorders was low (6.6%) but 39.2% of them were severe. Among ADRs, 10.2% were assessed as SAEs, the proportion of which was high at extreme ages and in males. Body as a whole-general disorders were the most frequently reported SOC for SAEs, followed by skin and appendage disorders. Antineoplastic agents and antibiotics were the most common causative agents of SAEs and ADRs. Anaphylactic reaction was the most frequent SAE (6.5%). Conclusions The proportion of SAE differs according to SOC and drug. Attention should be paid to SAEs in children and older adults because the rate of SAEs is significantly higher at extreme ages.

Purpose: Rituximab is prone to infusion-related reactions, which commonly requires desensitization to maintain its administration. Conventional desensitization protocols are using multistep infusion by diluting solutions. However, the process of diluting drugs and stepwise delivery needs additional time and effort. The objective of this study was to investigate the safety and efficacy of a nondiluting, one-bag protocol of rituximab desensitization. Methods: A retrospective study was performed by reviewing the medical records of patients who underwent rituximab desensitization between 2009 and 2018. The completion rate, occurrence and severity of breakthrough reactions (BTR), and time required to complete the therapy were compared between one-bag protocol and multibag protocol. Results were analyzed by generalized estimation equation method, and odds ratios (ORs) of completion rate and BTR incidence were estimated. Results: Total 190 cases of desensitization therapy were performed in 49 patients; the incidence of BTR was 16.84% and the overall completion rate was 96.32%. No significant difference in completion rate was found (OR, 3.58; 95% confidence interval [CI], 0.79– 16.38) and there was no significant difference in BTR incidence (OR, 0.81; 95% CI, 0.23–2.82) in one-bag protocol. BTR in the one-bag protocol tended to occur even through entire steps, whereas most of the BTR in the multibag protocol occurred at later steps of the process. The average time spent in the desensitization was 60 minutes shorter in the one-bag than the multibag protocol (258.15 minutes vs. 329.81 minutes, P< 0.001). Conclusion One-bag desensitization protocol showed no significant difference in safety and efficiency compared to the conventional multibag protocol, with shortening the time required for completion.

PURPOSE: To identify causative agents of the drug-induced anaphylaxis (DIA) by using the Korea Institute of Drug Safety & Risk Management-Korea Adverse Event Reporting System (KIDS-KAERS) database (Ministry of Food and Drug Safety) in Korea and to check their labeling information regarding anaphylaxis.METHODS: Among Individual Case Safety Reports from January, 2008 to December 2017, cases of DIA were analyzed for demographics, causative agents and fatal cases resulting in death. The domestic drug labeling, Micromedex and U.S. Food and Drug Administration (FDA) drug package insert, were reviewed to check if the labeling information on suspected causative agents contains anaphylaxis.RESULTS: A total of 4,700 cases of DIA were analyzed. The mean age was 49.85±18.32 years, and 2,642 patients (56.2%) were females. Among 8,664 drugs reported as causative agents, antibiotics (27.4%) accounted for the largest portion. There were 18 fatal cases: antibiotics (7 cases), antineoplastic agents (4 cases) were the major causative drugs for the mortality cases. Of 513 drugs reported as suspected causative agents, 103 (20.1%) did not list anaphylaxis as an adverse effect on domestic drug labeling and 16 (3.1%) did not reflect anaphylaxis in any of 3 adverse drug information.CONCLUSION: Analysis of 10-year data showed that antibiotics were the main cause of DIA and the mortality rate was 0.7%. In 3.1% of suspected drugs, there was no description of anaphylaxis in any of the drug labeling.
Anaphylaxis ; Anti-Bacterial Agents ; Antineoplastic Agents ; Demography ; Drug Labeling ; Female ; Humans ; Korea ; Mortality ; Pharmacovigilance ; United States Food and Drug Administration