Background/Objectives: Pediatric parotid malignancies are rare but represent a critical subset of head and neck cancers. This study integrates nationwide incidence trends in Korea with detailed surgical outcomes from a single tertiary institution to better understand the characteristics and management of these tumors.Materials & Methods: Nationwide data from the Korea Central Cancer Registry (1999-2019) were analyzed to assess trends in pediatric parotid malignancy incidence. A retrospective review was conducted on 31 pediatric parotidectomy cases at a tertiary hospital from 2011 to 2024. Clinical data, surgical methods, pathology results, and follow-up outcomes were examined. Results: Nationwide analysis revealed an annual mean of 9.0 ± 4.0 cases of pediatric parotid malignancies, with a significant rise in incidence among patients aged 10-19 years (APC 5.4%, 95% CI 1.1-9.8, p=0.016). Institutional data showed that the median age of patients underwent parotidectomy was 15.0 years, with males comprising 67.7%. Among 31 cases, 19 (61.3%) were benign, primarily pleomorphic adenomas (68.4%), and 12 (38.7%) were malignant, predominantly mucoepidermoid carcinoma (87.5%). Superficial or partial parotidectomy was the most common surgical approach (71.0%), and no unexpected complications or recurrences were observed. Conclusion Pediatric parotid malignancies in Korea exhibit rising incidence rates, particularly among teenagers. Surgical outcomes confirm the predominance of pleomorphic adenomas and mucoepidermoid carcinomas. Pediatric parotid surgery is a procedure with minimized complications and a promising prognosis. Tailored treatment strategies adapted to the unique characteristics of pediatric patients are essential to optimize outcomes.

Background/Objectives: Pediatric parotid malignancies are rare but represent a critical subset of head and neck cancers. This study integrates nationwide incidence trends in Korea with detailed surgical outcomes from a single tertiary institution to better understand the characteristics and management of these tumors.Materials & Methods: Nationwide data from the Korea Central Cancer Registry (1999-2019) were analyzed to assess trends in pediatric parotid malignancy incidence. A retrospective review was conducted on 31 pediatric parotidectomy cases at a tertiary hospital from 2011 to 2024. Clinical data, surgical methods, pathology results, and follow-up outcomes were examined. Results: Nationwide analysis revealed an annual mean of 9.0 ± 4.0 cases of pediatric parotid malignancies, with a significant rise in incidence among patients aged 10-19 years (APC 5.4%, 95% CI 1.1-9.8, p=0.016). Institutional data showed that the median age of patients underwent parotidectomy was 15.0 years, with males comprising 67.7%. Among 31 cases, 19 (61.3%) were benign, primarily pleomorphic adenomas (68.4%), and 12 (38.7%) were malignant, predominantly mucoepidermoid carcinoma (87.5%). Superficial or partial parotidectomy was the most common surgical approach (71.0%), and no unexpected complications or recurrences were observed. Conclusion Pediatric parotid malignancies in Korea exhibit rising incidence rates, particularly among teenagers. Surgical outcomes confirm the predominance of pleomorphic adenomas and mucoepidermoid carcinomas. Pediatric parotid surgery is a procedure with minimized complications and a promising prognosis. Tailored treatment strategies adapted to the unique characteristics of pediatric patients are essential to optimize outcomes.

Background/Objectives: Pediatric parotid malignancies are rare but represent a critical subset of head and neck cancers. This study integrates nationwide incidence trends in Korea with detailed surgical outcomes from a single tertiary institution to better understand the characteristics and management of these tumors.Materials & Methods: Nationwide data from the Korea Central Cancer Registry (1999-2019) were analyzed to assess trends in pediatric parotid malignancy incidence. A retrospective review was conducted on 31 pediatric parotidectomy cases at a tertiary hospital from 2011 to 2024. Clinical data, surgical methods, pathology results, and follow-up outcomes were examined. Results: Nationwide analysis revealed an annual mean of 9.0 ± 4.0 cases of pediatric parotid malignancies, with a significant rise in incidence among patients aged 10-19 years (APC 5.4%, 95% CI 1.1-9.8, p=0.016). Institutional data showed that the median age of patients underwent parotidectomy was 15.0 years, with males comprising 67.7%. Among 31 cases, 19 (61.3%) were benign, primarily pleomorphic adenomas (68.4%), and 12 (38.7%) were malignant, predominantly mucoepidermoid carcinoma (87.5%). Superficial or partial parotidectomy was the most common surgical approach (71.0%), and no unexpected complications or recurrences were observed. Conclusion Pediatric parotid malignancies in Korea exhibit rising incidence rates, particularly among teenagers. Surgical outcomes confirm the predominance of pleomorphic adenomas and mucoepidermoid carcinomas. Pediatric parotid surgery is a procedure with minimized complications and a promising prognosis. Tailored treatment strategies adapted to the unique characteristics of pediatric patients are essential to optimize outcomes.

Background/Objectives: Pediatric parotid malignancies are rare but represent a critical subset of head and neck cancers. This study integrates nationwide incidence trends in Korea with detailed surgical outcomes from a single tertiary institution to better understand the characteristics and management of these tumors.Materials & Methods: Nationwide data from the Korea Central Cancer Registry (1999-2019) were analyzed to assess trends in pediatric parotid malignancy incidence. A retrospective review was conducted on 31 pediatric parotidectomy cases at a tertiary hospital from 2011 to 2024. Clinical data, surgical methods, pathology results, and follow-up outcomes were examined. Results: Nationwide analysis revealed an annual mean of 9.0 ± 4.0 cases of pediatric parotid malignancies, with a significant rise in incidence among patients aged 10-19 years (APC 5.4%, 95% CI 1.1-9.8, p=0.016). Institutional data showed that the median age of patients underwent parotidectomy was 15.0 years, with males comprising 67.7%. Among 31 cases, 19 (61.3%) were benign, primarily pleomorphic adenomas (68.4%), and 12 (38.7%) were malignant, predominantly mucoepidermoid carcinoma (87.5%). Superficial or partial parotidectomy was the most common surgical approach (71.0%), and no unexpected complications or recurrences were observed. Conclusion Pediatric parotid malignancies in Korea exhibit rising incidence rates, particularly among teenagers. Surgical outcomes confirm the predominance of pleomorphic adenomas and mucoepidermoid carcinomas. Pediatric parotid surgery is a procedure with minimized complications and a promising prognosis. Tailored treatment strategies adapted to the unique characteristics of pediatric patients are essential to optimize outcomes.

Objectives: . Because climatic and air-pollution factors are known to influence the occurrence of respiratory diseases, we used these factors to develop machine learning models for predicting the occurrence of respiratory diseases. Methods: . We obtained the daily number of respiratory disease patients in Seoul. We used climatic and air-pollution factors to predict the daily number of patients treated for respiratory diseases per 10,000 inhabitants. We applied the relief-based feature selection algorithm to evaluate the importance of feature selection. We used the gradient boosting and Gaussian process regression (GPR) methods, respectively, to develop two different prediction models. We also employed the holdout cross-validation method, in which 75% of the data was used to train the model, and the remaining 25% was used to test the trained model. We determined the estimated number of respiratory disease patients by applying the developed prediction models to the test set. To evaluate the performance of each model, we calculated the coefficient of determination (R2) and the root mean square error (RMSE) between the original and estimated numbers of respiratory disease patients. We used the Shapley Additive exPlanations (SHAP) approach to interpret the estimated output of each machine learning model. Results: . Features with negative weights in the relief-based algorithm were excluded. When applying gradient boosting to unseen test data, R2 and RMSE were 0.68 and 13.8, respectively. For GPR, the R2 and RMSE were 0.67 and 13.9, respectively. SHAP analysis showed that reductions in average temperature, daylight duration, average humidity, sulfur dioxide (SO2), total solar insolation amount, and temperature difference increased the number of respiratory disease patients, whereas increases in atmospheric pressure, carbon monoxide (CO), and particulate matter ≤2.5 μm in aerodynamic diameter (PM2.5) increased the number of respiratory disease patients. Conclusion . We successfully developed models for predicting the occurrence of respiratory diseases using climatic and air-pollution factors. These models could evolve into public warning systems.

Background/Aims: Adenoid cystic carcinoma (ACC) is a rare salivary gland tumor characterized by indolence, with a high rate of local recurrence and distant metastasis. This study aimed to investigate the effect of concurrent chemoradiation (CCRT) on locally advanced unresectable ACC. Methods: We retrospectively analyzed clinical data from 10 patients with pathologically confirmed ACC of the head and neck who received CCRT with cisplatin in Seoul National University Hospital between 2013 and 2018. Results: Ten patients with unresectable disease at the time of diagnosis or with positive margins after surgical resection received CCRT with weekly cisplatin. Eight patients (80%) achieved complete remission, of which three later developed distant metastases without local relapse; one patient developed distant metastasis and local relapse. Two patient achieved partial remission without progression. Patients experienced several toxicities, including dry mouth, radiation dermatitis, nausea, and salivary gland inflammation of mostly grade 1 to 2. Only one patient showed grade 3 oral mucositis. Median relapse-free survival was 34.5 months (95% confidence interval, 22.8 months to not reached). Conclusions CCRT with cisplatin is effective for local control of ACC with manageable toxicity and may be an effective treatment option for locally advanced unresectable ACC.

Background/Aims: Omalizumab is the first biologic known to be effective in patients with severe allergic asthma. Methods: This study was conducted as a multicenter, single-group, open trial to evaluate the improvement in the quality of life with the additional administration of omalizumab for 24 weeks in Korean patients with severe persistent allergic asthma. Results: Of the 44 patients, 31.8% were men and the mean age was 49.8 ± 11.8 years. A score improvement of 0.5 points or more in the Quality of Life Questionnaire for Korean Asthmatics (KAQLQ) was noted in 50.0% (22/44) of the patinets. In the improved group, the baseline total immunoglobulin E (IgE) level and the amount of omalizumab used were higher, and the day and night asthma symptoms were more severe, compared to those in the non-improved group. According to the Global Evaluation of Treatment Effectiveness, favorable outcomes were found in 78.6% of patients. The Korean asthma control test (p < 0.005) and forced expiratory volume in 1 second % predicted (FEV1%; p < 0.01) improved significantly in patients who received omalizumab treatment, compared to that at week 0, and the total dose of rescue systemic corticosteroids significantly decreased (p < 0.05). The improved group on KAQLQ showed a significant improvement in FEV1% (p < 0.001). Conclusions Omalizumab can be considered a biological treatment for Korean patients with severe allergic asthma. It is recommended to consider omalizumab as add-on therapy in patients with high baseline total IgE levels and severe asthma symptoms.

Background/Aims: Omalizumab is the first biologic known to be effective in patients with severe allergic asthma. Methods: This study was conducted as a multicenter, single-group, open trial to evaluate the improvement in the quality of life with the additional administration of omalizumab for 24 weeks in Korean patients with severe persistent allergic asthma. Results: Of the 44 patients, 31.8% were men and the mean age was 49.8 ± 11.8 years. A score improvement of 0.5 points or more in the Quality of Life Questionnaire for Korean Asthmatics (KAQLQ) was noted in 50.0% (22/44) of the patinets. In the improved group, the baseline total immunoglobulin E (IgE) level and the amount of omalizumab used were higher, and the day and night asthma symptoms were more severe, compared to those in the non-improved group. According to the Global Evaluation of Treatment Effectiveness, favorable outcomes were found in 78.6% of patients. The Korean asthma control test (p < 0.005) and forced expiratory volume in 1 second % predicted (FEV1%; p < 0.01) improved significantly in patients who received omalizumab treatment, compared to that at week 0, and the total dose of rescue systemic corticosteroids significantly decreased (p < 0.05). The improved group on KAQLQ showed a significant improvement in FEV1% (p < 0.001). Conclusions Omalizumab can be considered a biological treatment for Korean patients with severe allergic asthma. It is recommended to consider omalizumab as add-on therapy in patients with high baseline total IgE levels and severe asthma symptoms.