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.

Purpose: Acute promyelocytic leukemia (APL) is a rare disease in children and there are some different characteristics between children and adult. We aimed to evaluate incidence, clinical characteristics and treatment outcomes of pediatric APL in Korea. Materials and Methods: Seventy-nine pediatric APL patients diagnosed from January 2009 to December 2016 in 16 tertiary medical centers in Korea were reviewed retrospectively. Results: Of 801 acute myeloid leukemia children, 79 (9.9%) were diagnosed with APL. The median age at diagnosis was 10.6 years (range, 1.3 to 18.0). Male and female ratio was 1:0.93. Thirty patients (38.0%) had white blood cell (WBC) count greater than 10×109/L at diagnosis. All patients received induction therapy consisting of all-trans retinoic acid and chemotherapy. Five patients (6.6%) died during induction chemotherapy and 66 patients (86.8%) achieved complete remission (CR) after induction chemotherapy. The causes of death were three intracranial hemorrhage, one cerebral infarction, and one sepsis. Five patients (7.1%) suffered a relapse during or after maintenance chemotherapy. The estimated 4-year event-free survival and overall survival (OS) rates were 82.1%±4.4%, 89.7%±5.1%, respectively. The 4-year OS was significantly higher in patients with initial WBC < 10×109/L than in those with initial WBC ≥ 10×109/L (p=0.020). Conclusion This study showed that the CR rates and survival outcomes in Korean pediatric APL patients were relatively good. The initial WBC count was the most important prognostic factor and most causes of death were related to serious bleeding in the early stage of treatment.

Background: Hodgkin's lymphoma (HL) constitutes 10%–20% of all malignant lymphomas and has a high cure rate (5-year survival, around 90%). Recently, interest has increased concerning preventing secondary complications (secondary cancer, endocrine disorders) in long-term survivors. We aimed to study the epidemiologic features and therapeutic outcomes of HL in children, adolescents, and young adults in Korea. Methods: We performed a multicenter, retrospective study of 224 patients aged < 25 years diagnosed with HL at 22 participating institutes in Korea from January 2007 to August 2016. Results: A higher percentage of males was diagnosed at a younger age. Nodular sclerosis histopathological HL subtype was most common, followed by mixed cellularity subtype.Eighty-one (36.2%), 101 (45.1%), and 42 (18.8%) patients were classified into low, intermediate, and high-risk groups, respectively. Doxorubicin, bleomycin, vinblastine, dacarbazine was the most common protocol (n = 102, 45.5%). Event-free survival rate was 86.0% ± 2.4%, while five-year overall survival (OS) rate was 96.1% ± 1.4%: 98.7% ± 1.3%, 97.7% ± 1.6%, and 86.5% ± 5.6% in the low, intermediate, and high-risk groups, respectively (P = 0.021). Five-year OS was worse in patients with B-symptoms, stage IV disease, highrisk, splenic involvement, extra-nodal lymphoma, and elevated lactate dehydrogenase level.In multivariate analysis, B-symptoms and extra-nodal involvement were prognostic factors for poor OS. Late complications of endocrine disorders and secondary malignancy were observed in 17 and 6 patients, respectively. Conclusion This is the first study on the epidemiology and treatment outcomes of HL in children, adolescents, and young adults in Korea. Future prospective studies are indicated to develop therapies that minimize treatment toxicity while maximizing cure rates in children, adolescents, and young adults with HL.

BACKGROUND: von Willebrand disease (VWD) is one of the most common inherited bleeding disorders. However, the number of patients who register to the Korea Hemophilia Foundation (KHF) is much lower than the expected prevalence rate and only few hospitals perform tests for diagnosis autonomously. Thus, we surveyed practical realities of VWD in Yeungnam region. METHODS: Patients with VWD (N=267) who were diagnosed at eleven university hospitals from March 1995 to March 2018 were enrolled in this study. We evaluated the medical records from each hospital retrospectively. RESULTS: Two hundred and twenty-eight children and 39 adults met the diagnostic criteria for VWD. Seventy-eight (57.4%) patients had the blood type O. Fifty-eight patients were definite type 1 (21.7%), 151 were possible type 1 (56.6%), and the others were type 2. Abnormal laboratory findings were the most common factor for the diagnosis in children. VWF mutations were detected in 17 patients. Patients with a family history showed age of diagnosis of 9 y, which is higher than in those with no family history (6 yr), and also showed a higher rate of significant bleeding (32.1% vs. 14.2%). VWF:RCo and VWF:Ag tests were performed in-hospital at only 1 of 11 hospitals. Twelve of 267 patients were enrolled at the KHF (4.5%). CONCLUSION: A high rate of out-sourcing studies may result in inaccurate diagnosis. The registration rate to the KHF is still lower than the prevalence rate. A comprehensive nationwide registration system is necessary in order to identify the actual prevalence rate and promote the diagnosis of VWD in Korea.
Adult ; Child ; Diagnosis ; Hemophilia A ; Hemorrhage ; Hospitals, University ; Humans ; Korea ; Medical Records ; Prevalence ; Retrospective Studies ; von Willebrand Diseases

BACKGROUND/AIMS: When determining the subsequent management after endoscopic resection of the early colon cancer (ECC), various factors including the margin status should be considered. This study assessed the subsequent management and outcomes of ECCs according to margin status.METHODS: We examined the data of 223 ECCs treated by endoscopic mucosal resection (EMR) from 215 patients during 2004 to 2014, and all patients were followed-up at least for 2 years.RESULTS: According to histological analyses, the margin statuses of all lesions after EMR were as follows: 138 cases (61.9%) were negative, 65 cases (29.1%) were positive for dysplastic cells on the resection margins, and 20 cases (8.9%) were uncertain. The decision regarding subsequent management was affected not only by pathologic outcomes but also by the endoscopist’s opinion on whether complete resection was obtained. Surgery was preferred if the lesion extended to the submucosa (odds ratio [OR], 25.46; 95% confidence interval [CI], 7.09–91.42), the endoscopic resection was presumed incomplete (OR, 15.55; 95% CI, 4.28–56.56), or the lymph system was invaded (OR, 13.69; 95% CI, 1.76–106.57). Fourteen patients (6.2%) had residual or recurrent malignancies at the site of the previous ECC resection and were significantly associated with presumed incomplete endoscopic resection (OR, 4.59; 95% CI, 1.21–17.39) and submucosal invasion (OR, 5.14; 95% CI, 1.18–22.34).CONCLUSIONS: Subsequent surgery was associated with submucosa invasion, lymphatic invasion, and cancer-positive margins. Presumed completeness of the resection may be helpful for guiding the subsequent management of patients who undergo endoscopic resection of ECC.
Colon ; Colonic Neoplasms ; Humans

BACKGROUND: Venous thromboembolism (VTE) is rare in pediatric patients compared to adults, but it's incidence is gradually increasing. The purpose of this study was to analyze the incidence, risk factors, and prognosis of pediatric patients with VTE in Korea. METHODS: Between January 2000 and July 2017, 249,312 medical records of the patients older than 1 year who were hospitalized in the department of pediatrics of 10 university hospitals in Yeungnam region were retrospectively reviewed. RESULTS: The overall incidence of VTE was 4.9 per 10,000 admissions. Of the total 123 patients, 80 (65.0%) were male and the median age was 10.8 years (range, 1.0–23.5 years). Magnetic resonance imaging was performed most frequently to confirm the diagnosis of VTE (43.1%). Thrombosis occurred in the cerebral vessels (46.3%), lower extremities (23.8%), pulmonary (19.5%), abdomen (9.8%), and upper extremities (4.1%). One hundred and six patients had underlying causes such as cancer (27.6%), infection (26.8%), intravenous catheter insertion (17.9%), and surgery (14.6%). Protein C was evaluated in 39 patients (31.7%), protein S in 40 (32.5%), antithrombin (AT) III in 52 (42.3%), and homocysteine in 21 (17.1%). Among them, one patient with a family history of AT III deficiency had SERPINC gene mutation. Seventy-seven patients (62.6%) started anticoagulation treatment. Most (52.0%) were treated for more than 90 days. CONCLUSION: Healthcare providers must be aware of the potential for VTE development in childhood. In the near future, a nationwide survey should be investigated to determine the incidence rate and the trends in VTE among Korean children.
Abdomen ; Adult ; Catheters ; Child ; Diagnosis ; Epidemiology ; Health Personnel ; Homocysteine ; Hospitals, University ; Humans ; Incidence ; Korea* ; Lower Extremity ; Magnetic Resonance Imaging ; Male ; Medical Records ; Pediatrics ; Prognosis ; Protein C ; Protein S ; Retrospective Studies ; Risk Factors ; Thrombosis ; Upper Extremity ; Venous Thromboembolism*

Cytomegalovirus (CMV) reactivation is common in patients with severe ulcerative colitis (UC), and may ref lect exacerbation of mucosal inf lammation and/or administration of immunosuppressants. The question of whether CMV is an active pathogen or ‘an innocent bystander’ in the exacerbation of UC remains controversial. Patients with UC exacerbated by reactivated CMV experience worse prognoses than those without CMV reactivation and antiviral therapy significantly reduces the need for colectomy in patients with severe UC and high-grade CMV infection, indicating that CMV plays a role in UC prognosis. Therefore, the CMV status of patients on immunosuppressants, particularly those with steroid-refractory or -dependent UC, should be tested. When CMV is detected, be performed based on should adequate treatment the extent of the viral load and the presence of certain clinical features including a large ulcer. Anti-tumor necrosis factor agents may be useful for treating CMV colitis complicating UC.
Colectomy ; Colitis ; Colitis, Ulcerative* ; Cytomegalovirus Infections* ; Cytomegalovirus* ; Humans ; Immunosuppressive Agents ; Necrosis ; Prognosis ; Ulcer* ; Viral Load