Purpose: Renal tumors account for approximately 7% of all childhood cancers. These include Wilms tumor (WT), clear cell sarcoma of the kidney (CCSK), malignant rhabdoid tumor of the kidney (MRTK), renal cell carcinoma (RCC), congenital mesoblastic nephroma (CMN) and other rare tumors. We investigated the epidemiology of pediatric renal tumors in Korea. Materials and Methods: From January 2001 to December 2015, data of pediatric patients (0–18 years) newly-diagnosed with renal tumors at 26 hospitals were retrospectively analyzed. Results: Among 439 patients (male, 240), the most common tumor was WT (n=342, 77.9%), followed by RCC (n=36, 8.2%), CCSK (n=24, 5.5%), MRTK (n=16, 3.6%), CMN (n=12, 2.7%), and others (n=9, 2.1%). Median age at diagnosis was 27.1 months (range 0-225.5) and median follow-up duration was 88.5 months (range 0-211.6). Overall, 32 patients died, of whom 17, 11, 1, and 3 died of relapse, progressive disease, second malignant neoplasm, and treatment-related mortality. Five-year overall survival and event free survival were 97.2% and 84.8% in WT, 90.6% and 82.1% in RCC, 81.1% and 63.6% in CCSK, 60.3% and 56.2% in MRTK, and 100% and 91.7% in CMN, respectively (p < 0.001). Conclusion The pediatric renal tumor types in Korea are similar to those previously reported in other countries. WT accounted for a large proportion and survival was excellent. Non-Wilms renal tumors included a variety of tumors and showed inferior outcome, especially MRTK. Further efforts are necessary to optimize the treatment and analyze the genetic characteristics of pediatric renal tumors in Korea.

Objectives: A retrospective cohort study was conducted to evaluate the effects of combination oral contraceptives (COCs) on bone mineral density (BMD) and metabolism in perimenopausal Korean women. Methods: The study subjects comprised two groups. The COC group included 55 women who took low-dose COC for at least one year to control vasomotor symptoms. Another 55 women who had annual checkups without history of COC use served as controls. BMD and bone turnover markers were assessed periodically. Results: In the control group, 12-month BMD values at the lumbar spine (LS) and total hip (TH) significantly decreased with a greater magnitude at LS, and bone resorption (BR) and formation (BF) markers increased concurrently with a larger change in BR. COCs increased BMD at LS after 12 months and prevented BMD decline at TH. Multivariable linear regression revealed a significant difference in LS BMD between groups at 12 months. In the COC group, there were significant negative correlations between baseline BMD and Z-score at LS and corresponding changes at 12 months. COCs did not alter BR markers, whereas BF markers were significantly decreased at 3 months. Group comparison at 12 months, as tested with adjusted linear regression, disclosed significant differences in both BR and BF makers. Conclusions Bone loss associated with activated bone turnover is evident during the menopausal transition, and COCs might prevent BMD decrease and suppress bone turnover markers in perimenopausal Korean women. Significant increase in LS BMD and decreases in BF makers suggest underlying mechanisms of greater impact on BF.

Background/Aims: The prospective Crohn’s Disease Clinical Network and Cohort Study is a nationwide multicenter cohort study of patients with Crohn’s disease (CD) in Korea, aiming to prospectively investigate the clinical features and long-term prognosis associated with CD. Methods: Patients diagnosed with CD between January 2009 and September 2019 were prospectively enrolled. They were divided into two cohorts according to the year of diagnosis: cohort 1 (diagnosed between 2009 and 2011) versus cohort 2 (between 2012 and 2019). Results: A total of 1,175 patients were included, and the median follow-up duration was 68 months (interquartile range, 39.0 to 91.0 months). The treatment-free durations for thiopurines (p<0.001) and anti-tumor necrosis factor agents (p=0.018) of cohort 2 were shorter than those of cohort 1. Among 887 patients with B1 behavior at diagnosis, 149 patients (16.8%) progressed to either B2 or B3 behavior during follow-up. Early use of thiopurine was associated with a reduced risk of behavioral progression (adjusted hazard ratio [aHR], 0.69; 95% confidence interval [CI], 0.50 to 0.90), and family history of inflammatory bowel disease was associated with an increased risk of behavioral progression (aHR, 2.29; 95% CI, 1.16 to 4.50). One hundred forty-one patients (12.0%) underwent intestinal resection, and the intestinal resection-free survival time was significantly longer in cohort 2 than in cohort 1 (p=0.003). The early use of thiopurines (aHR, 0.35;95% CI, 0.23 to 0.51) was independently associated with a reduced risk of intestinal resection. Conclusions The prognosis of CD in Korea appears to have improved over time, as evidenced by the decreasing intestinal resection rate. Early use of thiopurines was associated with an improved prognosis represented by a reduced risk of intestinal resection.

Background: and Purpose Data regarding the effects of cannabidiol (CBD) on the quality of life (QOL) are currently inadequate. We assessed the QOL of pediatric patients with epilepsy who were treated with CBD. Methods: This prospective, open-label study included pediatric and adolescent patients (aged 2–18 years) with Dravet syndrome or Lennox-Gastaut syndrome. Oral CBD was administered at 10 mg/kg/day. The Korean version of the Quality Of Life in Childhood Epilepsy (QOLCE) questionnaire was administered when CBD treatment began and again after 6 months. Adaptive behavior was measured using the Korean versions of the Child Behavior Checklist (K-CBCL) and the second edition of the Vineland Adaptive Behavior Scales (Vineland-II). Results: This study included 41 patients (11 with Dravet syndrome and 30 with LennoxGastaut syndrome), of which 25 were male. The median age was 4.1 years. After 6 months, 26.8% (11/41) of patients experienced a ≥50% reduction in the number of seizures. The total score for the QOLCE questionnaire did not change from baseline to after 6 months of CBD treatment (85.71±39.65 vs. 83.12±48.01, respectively; p=0.630). The score in the motor skills domain of Vineland-II reduced from 48.67±13.43 at baseline to 45.18±14.08 after 6 months of treatment (p=0.005). No other Vineland-II scores and no K-CBCL scores had changed after 6 months of CBD treatment. Conclusions CBD is an efficacious antiseizure drug used to treat Dravet syndrome and Lennox-Gastaut syndrome. However, it did not improve the patient QOL in our study, possibly because all of our patients had profound intellectual disabilities.

Purpose: This study evaluated the efficacy of adjuvant chemotherapy (AC) in patients with resected ampulla of Vater (AoV) carcinoma. Materials and Methods: Data from 646 patients who underwent surgical resection at Asan Medical Center between 2000 and 2017 were retrospectively reviewed. Results: The median age of the patients was 62 years, and 54.2% were male. Patients were classified into AC group (n=165, 25.5%) and no AC group (n=481, 74.5%). With a median follow-up duration of 88 months, in patients with stage I, II, III, median recurrence-free survival (RFS) was not reached, 44 months, and 15 months, respectively, and the median overall survival (OS) were not reached, 88 months and 35 months, respectively. Despite no statistical significance, RFS and OS were better in stage II patients with AC than in those without AC (median RFS, 151 months vs. 38 months; p=0.156 and median OS, 153 months vs. 74 months; p=0.299). In multivariate analysis for RFS and OS, TNM stage, R1 resection status, presence of lymphovascular invasion, and perineural invasion remained significant factors, whereas AC (hazard ratio [HR], 0.74; 95% confidence interval [CI], 0.54 to 1.00; p=0.052) was marginally related with RFS. After propensity score matching in only stage II/III patients, RFS and OS with AC were numerically longer than those without AC (HR, 0.80; 95% CI, 0.60 to 1.06; p=0.116 and HR, 0.77; 95% CI, 0.56 to 1.06; p=0.111). Conclusion AC with fluoropyrimidine did not improve survival of patients with resected AoV carcinoma. However, multivariate analysis with prognostic factors showed a marginally significant survival benefit with AC.

Decision-making for treatment of newly diagnosed prostate cancer (PCa) is complex due to the multiple initial treatment modalities available. We aimed to externally validate the SCaP (Severance Study Group of Prostate Cancer) Survival Calculator that incorporates a long short-term memory artificial neural network (ANN) model to estimate survival outcomes of PCa according to initial treatment modality. Materials and Methods The validation cohort consisted of clinicopathological data of 4,415 patients diagnosed with biopsy-proven PCa between April 2005 and November 2018 at three institutions. Area under the curves (AUCs) and time-to-event calibration plots were utilized to determine the predictive accuracies of the SCaP Survival Calculator in terms of progression to castration-resistant PCa (CRPC)–free survival, cancer-specific survival (CSS), and overall survival (OS). Results Excellent discrimination was observed for CRPC-free survival, CSS, and OS outcomes, with AUCs of 0.962, 0.944, and 0.884 for 5-year outcomes and 0.959, 0.928, and 0.854 for 10-year outcomes, respectively. The AUC values were higher for all survival endpoints compared to those of the development cohort. Calibration plots showed that predicted probabilities of 5-year survival endpoints had concordance comparable to those of the observed frequencies. However, calibration performances declined for 10-year predictions with an overall underestimation. Conclusion The SCaP Survival Calculator is a reliable and useful tool for determining the optimal initial treatment modality and for guiding survival predictions for patients with newly diagnosed PCa. Further modifications in the ANN model incorporating cases with more extended follow-up periods are warranted to improve the ANN model for long-term predictions.

Purpose: This study evaluated the efficacy of adjuvant chemotherapy (AC) in patients with resected ampulla of Vater (AoV) carcinoma. Materials and Methods: Data from 646 patients who underwent surgical resection at Asan Medical Center between 2000 and 2017 were retrospectively reviewed. Results: The median age of the patients was 62 years, and 54.2% were male. Patients were classified into AC group (n=165, 25.5%) and no AC group (n=481, 74.5%). With a median follow-up duration of 88 months, in patients with stage I, II, III, median recurrence-free survival (RFS) was not reached, 44 months, and 15 months, respectively, and the median overall survival (OS) were not reached, 88 months and 35 months, respectively. Despite no statistical significance, RFS and OS were better in stage II patients with AC than in those without AC (median RFS, 151 months vs. 38 months; p=0.156 and median OS, 153 months vs. 74 months; p=0.299). In multivariate analysis for RFS and OS, TNM stage, R1 resection status, presence of lymphovascular invasion, and perineural invasion remained significant factors, whereas AC (hazard ratio [HR], 0.74; 95% confidence interval [CI], 0.54 to 1.00; p=0.052) was marginally related with RFS. After propensity score matching in only stage II/III patients, RFS and OS with AC were numerically longer than those without AC (HR, 0.80; 95% CI, 0.60 to 1.06; p=0.116 and HR, 0.77; 95% CI, 0.56 to 1.06; p=0.111). Conclusion AC with fluoropyrimidine did not improve survival of patients with resected AoV carcinoma. However, multivariate analysis with prognostic factors showed a marginally significant survival benefit with AC.

Decision-making for treatment of newly diagnosed prostate cancer (PCa) is complex due to the multiple initial treatment modalities available. We aimed to externally validate the SCaP (Severance Study Group of Prostate Cancer) Survival Calculator that incorporates a long short-term memory artificial neural network (ANN) model to estimate survival outcomes of PCa according to initial treatment modality. Materials and Methods The validation cohort consisted of clinicopathological data of 4,415 patients diagnosed with biopsy-proven PCa between April 2005 and November 2018 at three institutions. Area under the curves (AUCs) and time-to-event calibration plots were utilized to determine the predictive accuracies of the SCaP Survival Calculator in terms of progression to castration-resistant PCa (CRPC)–free survival, cancer-specific survival (CSS), and overall survival (OS). Results Excellent discrimination was observed for CRPC-free survival, CSS, and OS outcomes, with AUCs of 0.962, 0.944, and 0.884 for 5-year outcomes and 0.959, 0.928, and 0.854 for 10-year outcomes, respectively. The AUC values were higher for all survival endpoints compared to those of the development cohort. Calibration plots showed that predicted probabilities of 5-year survival endpoints had concordance comparable to those of the observed frequencies. However, calibration performances declined for 10-year predictions with an overall underestimation. Conclusion The SCaP Survival Calculator is a reliable and useful tool for determining the optimal initial treatment modality and for guiding survival predictions for patients with newly diagnosed PCa. Further modifications in the ANN model incorporating cases with more extended follow-up periods are warranted to improve the ANN model for long-term predictions.