Excellent Outcomes in Children, Adolescents, and Young Adults with Ovarian Germ Cell Tumors Treated by Either Reduced- or Standard-Dose Bleomycin.

To investigate the outcomes of children, adolescents, and young adults (AYAs) with malignant ovarian germ cell tumors (MOGCTs), we analyzed the data of 61 patients aged ≤39 years diagnosed with MOGCT between 2006 and 2022. Among 59 patients who received chemotherapy after initial diagnosis, 57 received BEP (standard dose of bleomycin with 30 units per week, n = 13) or bEP (reduced dose of bleomycin with 15 units/m2 on day 1, n = 44). The 5-year overall survival (OS) and event-free survival (EFS) rates were 98.3% and 84.9%, respectively. Reduced bleomycin dose did not adversely affect survival. Normalization of tumor markers within 3 months after surgery was significantly associated with better EFS (p < 0.01). Of the 59 surviving patients, 8 experienced surgery-related menopause, while 49 demonstrated menstrual recovery. After completion of chemotherapy, there was no significant difference in pulmonary function regarding bleomycin dose, and no overt nephrotoxicity. Approximately 60% and 25% of survivors experienced peripheral neuropathy at the end of chemotherapy and after 1 year, respectively (p < 0.01). Children and AYAs with MOGCT have favorable survival rates with minimal long-term toxicity, which are not influenced by a reduced bleomycin dose. Rapid normalization of tumor markers is associated with improved outcomes.

Clinical characteristics and long-term outcomes of rhabdomyosarcoma in Korean children, adolescents and young adults: a single-center experience.

PURPOSE: This study aimed to analyze characteristics, treatment, long-term outcomes, and prognostic factors for children, adolescents and young adults with rhabdomysosarcoma (RMS). METHODS: This retrospective historical study included 75 patients with RMS treated between 2002 and 2019. Clinical data and follow-up results were collected including all diagnosis, treatment and prognosis information. RESULTS: Patients median-age-at-diagnosis was 6 years. Embryonal and alveolar histology occurred in 51 (68.0%) and 21 (28.0%) patients, respectively. The tumors most frequently originated from parameningeal site (28.0%). Of 74 evaluable patients for treatment outcome, 60 (81.1%) achieved complete response for first-line treatment, of whom, 34 (56.6%) maintained complete response, 26 (43.3%; 23/26, local relapse) showed relapse. Of 40 patients with treatment failure, 16 and 6 occurred in parameningeal area and retroperitoneum/perineum, respectively. The 5-year progression-free survival (PFS) and overall survival (OS) were 45.0% and 64.5%, respectively. In multivariate analyses, parameningeal site (p = 0.027), no gross total resection (p = 0.047), and no radiation therapy (RT) (p < 0.001) for PFS; and parameningeal site (p < 0.001) and no RT (p = 0.010) for worse OS, were significant. The median PFS and OS from treatment failure date in 40 patients with primary treatment failure were 1.3 and 4.1 years, respectively. Of 26 patients with relapse, interval to relapse < 7 months, retroperitoneum/perineum site, TNM stages III/IIV, and no salvage RT were independently associated with OS. CONCLUSION: The importance of adequate local therapy was highlighted in RMS treatment. Treatment failure was largely a local failure. Whether as a component of initial or salvage treatment, RT could improve patients' survival.

Epidemiologic and Clinical Outcomes of Pediatric Renal Tumors in Korea: A Retrospective Analysis of The Korean Pediatric Hematology and Oncology Group (KPHOG) Data.

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.

ICSBP-induced PD-L1 enhances osteosarcoma cell growth.

Background: Interferon (IFN) consensus sequence binding protein (ICSBP) is a transcription factor induced by IFN-γ. We previously reported that ICSBP expression promotes osteosarcoma progression by enhancing transforming growth factor-ß signaling. In cancer cells, programmed death-ligand 1 (PD-L1) contributes to immune escape and may also be involved in tumor progression. Because IFN-γ induces the expression of both ICSBP and PD-L1, we explored the association between ICSBP and PD-L1 expression in terms of osteosarcoma progression. Methods: Three osteosarcoma cell lines (Saos2, U2OS, and 143B) were employed. Gene expression was measured by qRT-PCR, and protein levels were assessed by immunoblotting. PD-L1 expression was evaluated in cells overexpressing ICSBP and in ICSBP knockdown cells. The effects of PD-L1 expression on cell growth were examined by MTS assays, Incucyte analysis, soft agar assays, and three-dimensional (3D) culture. Cell cycle and apoptosis were evaluated by FACS analysis of cells stained with propidium iodide (PI) and annexin V/PI, respectively. The antitumor effects of PD-L1 knockdown without or with doxorubicin treatment were evaluated in vivo in nude mice bearing ICSBP-overexpressing 143B cell xenograft. The clinical relevance of PD-L1 and ICSBP expression was evaluated immunohistochemically using a human osteosarcoma microarray and through analysis of publicly available data using Gene Expression Profiling Interactive Analysis2. Results: ICSBP overexpression upregulated PD-L1 expression in all three cell lines, whereas ICSBP knockdown decreased the PD-L1 expression. PD-L1 knockdown attenuated the cell growth and reduced colony-forming capacity in both soft agar assays and 3D culture. PD-L1 knockdown increased apoptosis and induced G2/M arrest, which was associated with decreased expression of survivin, cyclin-dependent kinase 4 (CDK4), cyclin E, and cyclin D1 expression and increased the expression of p27, phosphorylated Cdc2, and phosphorylated Wee1. PD-L1 knockdown decreased the growth of tumor xenografts and increased the doxorubicin sensitivity of ICSBP-overexpressing 143B cells both in vitro and in vivo. PD-L1 was expressed in human osteosarcoma tissues, and its expression was moderately correlated with that of ICSBP in osteosarcoma patients. Conclusion: ICSBP regulates PD-L1 expression in osteosarcoma cells, and PD-L1 knockdown combined with doxorubicin treatment could represent a strategy for controlling osteosarcoma expressing ICSBP.

Vincristine, Irinotecan, and Temozolomide as a Salvage Regimen for Relapsed or Refractory Sarcoma in Children and Young Adults.

PURPOSE: No standard salvage regimen is available for relapsed or refractory sarcoma. We investigated the efficacy and toxicity of the vincristine, irinotecan, and temozolomide combination (VIT) for relapsed or refractory sarcomas of variable histology in children and young adults. MATERIALS AND METHODS: We retrospectively reviewed data from the relapsed or refractory sarcoma patients who were treated with VIT. The VIT protocol was given every 3 weeks as follows: vincristine, 1.5 mg/m2 intravenously on day 1, irinotecan, 50 mg/m2/day intravenously on days 1-5, and temozolomide, 100 mg/m2/day orally on days 1-5. RESULTS: A total of 26 patients (12 males) with various sarcoma histology were included in the study. Most common diagnosis was rhabdomyosarcoma (n=8) followed by osteosarcoma (n=7). Median age at the start of VIT was 18.5 years (range, 2.0 to 39.9). VIT was delivered as 2nd to 7th line of treatment, with 4th line most common (9/26, 34.6%). Median number of VIT courses given was 3 (range, 1 to 18). Of the 25 evaluable patients, there was two partial response (PR) and 11 stable disease (SD) with an overall control rate (complete remission+PR+SD) of 52%. PR was seen in one (50%) of the two evaluable patients with Ewing sarcoma and one (14.3%) of the seven patients with osteosarcoma. Overall survival and progression-free survival rates were 79.3% and 33.9% at 1 year, and 45.5% and 25.4% at 2 years, respectively. There was no treatment-related mortality. CONCLUSION: The VIT regimen was effective and relatively safe in our cohort of sarcoma patients.

Incidence and outcomes of malignant ovarian germ cell tumors in Korea, 1999-2017.

OBJECTIVE: Malignant ovarian germ cell tumor (MOGCT) is a rare ovarian malignancy accounting for less than 5% of all ovarian cancers. We aimed to evaluate the incidence, survival, and subsequent malignancies after the diagnosis of MOGCT. METHODS: Data from the Korea Central Cancer Registry were used to identify MOGCTs between 1999 and 2017. The age-standardized rates (ASRs), 5-year relative survival rates (RSR) and standardized incidence ratio (SIR) for subsequent cancer after diagnosis of MOGCT were estimated. RESULTS: Of 2125 cases of newly diagnosed MOGCTs, 596 (28.0%) were diagnosed with dysgerminoma and 1529 (72.0%) with non-dysgerminoma. The ASR per 100,000 women-years was 0.539; ASR slightly increased over the study period (annual percent change [APC] = 1.01%; p = 0.02). There was an increase and decrease in the incidence of MOGCTs in the age groups 0-19 years (APC = 1.96%; p < 0.01) and ≥ 50 years (APC = -6.51%; p < 0.01), respectively. Patients with dysgerminoma showed significantly higher RSR than patients with non-dysgerminoma (98.0% vs. 94.9%, p < 0.01). Patients aged ≥50 years showed worst 5-year RSR (68.7%) than patients aged 0-19 years (97.8%) and 20-34 years (96.4%) (p < 0.01). The overall SIR for a subsequent cancer occurrence was 2.07, with the most frequent site of subsequent primary cancer being the thyroid (SIR = 2.78). CONCLUSIONS: Our data demonstrated an excellent prognosis of MOGCTs among Korean women. There was a slight increase in MOGCT prevalence, which was more pronounced among those aged <19 years. After MOGCT diagnosis, the risk of developing a subsequent malignancy was doubled compared with the general population.

Erratum: Correction of Affiliations in the Article "Clinical Characteristics and Treatment Outcomes in Children, Adolescents, and Young-adults with Hodgkin's Lymphoma: a KPHOG Lymphoma Working-party, Multicenter, Retrospective Study".

This corrects the article on p. e393 in vol. 35, PMID: 33258329.

Cancer Incidence and Survival among Adolescents and Young Adults in Korea: An Update for 2016.

PURPOSE: This study investigated the incidence and relative survival rates (RSRs) for cancers among adolescents and young adults (AYAs) aged 15-39 years between 1993 and 2016 in Korea. MATERIALS AND METHODS: Data from the Korea Central Cancer Registry were used to calculate percent distributions, age-specific incidence rates, age-standardized incidence rates (ASRs) per million, annual percent changes (APCs), average APCs, and RSRs for cancers diagnosed in AYAs. RESULTS: ASR of all cancers among AYAs was 654.5 per million. The largest diagnosed group of cancers was carcinomas (almost 80%). Crude incidence increased with age, from 170.4 per million for those aged 15-19 years to 1,639.8 per million for those aged 35-39 years. ASR increased from 414.8 per million to 820.4 per million, with an APC of 9.0%. The incidence of thyroid carcinoma showed the most rapid increment (APC, 14.0%), followed by non-Hodgkin lymphoma (APC, 13.4%). The 5-year RSR among AYAs significantly improved from 62.1% to 90.8%. Survival improvement in AYAs was higher than that in children but lower than that in older adults (APC, 2.1% vs. 1.9% vs. 3.1%). The most marked survival improvement was found for leukemia and lymphoma. Astrocytoma, rhabdomyosarcoma, and carcinoma of the trachea, bronchus, and lung had a 5-year RSR of < 50%. CONCLUSION: There was an improvement in cancer survivals in AYAs, comparable to that achieved in children. However, survivals in several cancer types do not appear to be improving. Further research focusing on the epidemiology and therapeutic strategies for cancers in AYAs is needed.

Hyperammonemic Encephalopathy Mimicking Ornithine Transcarbamylase Deficiency in Fibrolamellar Hepatocellular Carcinoma: Successful Treatment with Continuous Venovenous Hemofiltration and Ammonia Scavengers.

Fibrolamellar hepatocellular carcinoma (FLHCC) is a rare liver cancer affecting adolescents and young adults without any pre existing liver disease. Hyperammonemic encephalopathy (HAE) is a serious paraneoplastic syndrome, and several cases of HAE have been reported in patients with FLHCC. This condition is rare; hence, there are currently no management guidelines for cancer-related HAE. Herein, we report a case of an 18-year-old man with advanced FLHCC who developed HAE during the first course of chemotherapy consisting of cisplatin, doxorubicin, 5-fluorouracil, and interferon-α. He was successfully treated with continuous venovenous hemofiltration, sodium benzoate, sodium phenylbutyrate, and amino acid supplementation for HAE. After the second course of chemotherapy, he underwent surgery, and thereafter, his ammonia levels were normal without any ammonia scavenger therapy. Treatments for HAE described here will be helpful for this rare, but serious metabolic complication of FLHCC and could partially applied to HAE related to any malignancies.

Clinical Characteristics and Treatment Outcomes in Children, Adolescents, and Young-adults with Hodgkin's Lymphoma: a KPHOG Lymphoma Working-party, Multicenter, Retrospective Study.

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, high-risk, 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.

Successful Sirolimus Treatment for Korean Patients with Activated Phosphoinositide 3-kinase δ Syndrome 1: the First Case Series in Korea.

Activated phosphoinositide 3-kinase δ syndrome (APDS)1 is caused by gain-of-function mutations in PIK3CD, which encodes the catalytic p110δ subunit of phosphoinositide 3 kinase. We describe three patients with APDS1, the first thereof in Korea. Therein, we investigated clinical manifestations of APDS1 and collected data on the efficacy and safety profile of sirolimus, a mammalian target of rapamycin inhibitor and pathway-specific targeted medicine. The same heterozygous PIK3CD mutation was detected in all three patients (E1021K). After genetic diagnosis, all patients received sirolimus and experienced an excellent response, including amelioration of lymphoproliferation and improvement of nodular mucosal lymphoid hyperplasia in the gastrointestinal tract. The median trough level of sirolimus was 5.5 ng/mL (range, 2.8-7.5) at a dose of 2.6-3.6 mg/m². Two patients who needed high-dose, short-interval, immunoglobulin-replacement treatment (IGRT) had a reduced requirement for IGRT after initiating sirolimus, and the dosing interval was extended from 2 and 3 weeks to 4 weeks. The IgG trough level after sirolimus treatment (median, 594 mg/dL; range, 332-799 mg/dL) was significantly higher than that before sirolimus treatment (median, 290 mg/dL; range, 163-346 mg/dL) (p<0.001). One episode of elevated serum creatinine with a surge of sirolimus (Patient 2) and episodes of neutropenia and oral stomatitis (Patient 1) were observed. We diagnosed the first three patients with APDS1 in Korea. Low-dose sirolimus may alleviate clinical manifestations thereof, including hypogammaglobulinemia.

Korean parents' perceptions of the challenges and needs on school re-entry during or after childhood and adolescent cancer: a multi-institutional survey by Korean Society of Pediatric Hematology and Oncology.

BACKGROUND: For children and adolescents with cancer, going back to school is a key milestone in returning to "normal life." PURPOSE: To identify the support vital for a successful transition, we evaluated the parents' needs and the challenges they face when their children return to school. METHODS: This multi-institutional study was conducted by the Korean Society of Pediatric Hematology and Oncology. The written survey comprised 24 questions and was completed by 210 parents without an interviewer. RESULTS: Most parents (165 of 206) reported that their children experienced difficulties with physical status (n=60), peer relationships (n=30), academic performance (n=27), emotional/behavioral issues (n=11), and relationships with teachers (n=4) on reentering school. Parents wanted to be kept informed about and remain involved in their children's school lives and reported good parent-teacher communication (88 of 209, 42.1%). Parents reported that 83.1% and 44.9% of teachers and peers, respectively, displayed an adequate understanding of their children's condition. Most parents (197 of 208) answered that a special program is necessary to facilitate return to school after cancer therapy that offers emotional support (n=85), facilitates social adaptation (n=61), and provides tutoring to accelerate catch up (n=56), and continued health care by hospital outreach and school personnel (n=50). CONCLUSION: In addition to scholastic aptitude-oriented programs, emotional and psychosocial support is necessary for a successful return to school. Pediatric oncologists should actively improve oncology practices to better integrate individualized school plans and educate peers and teachers to improve health literacy to aid them in understanding the needs of children with cancer.

Histologic Response and Toxicity following Interval-Compressed Four-Drug Therapy Given Preoperatively in Children and Young Adults with Osteosarcoma: A Retrospective Study.

OBJECTIVES: The histologic response to chemotherapy is an important prognostic factor in osteosarcoma. Thus, we attempted to develop an effective neoadjuvant regimen to achieve an improvement in histologic response. METHODS: Twenty-nine patients with a high-grade osteosarcoma received 2 courses of neoadjuvant chemotherapy non-randomly with either the MAP regimen (methotrexate 12 g/m2, cisplatin 120 mg/m2, and doxorubicin 75 mg/m2) or MAPI regimen (MAP plus ifosfamide 9 g/m2). We applied interval compression to MAPI by shortening the preoperative period to be aligned with that of MAP. Adjuvant chemotherapy was tailored according to the necrosis rate of resected tumor specimens. Necrosis rate, toxicity, and survival outcome were compared retrospectively between the 2 groups. RESULTS: The median interval between the beginning of neoadjuvant chemotherapy and surgery was 97.0 days in the MAPI group (17 patients) and 90.5 days in the MAP group (12 patients; p = 0.19). The good histologic response (>90% of necrosis) was observed in 71% of MAPI and in 42% of MAP (p = 0.12). Major toxicities of grade 3 or worse were not different between the 2 groups. The probability of 5-year progression-free survival and overall survival of the MAPI group were 74 and 83%, and those in the MAP group were 50 and 75%, showing no difference. CONCLUSIONS: Interval-compressed MAPI therapy given in a similar duration of the preoperative phase to that of conventional MAP therapy showed a marginal trend toward a better histologic response without a significant increase in major toxicities. Regarding the proportion of good histologic response, 71% is one of the highest values ever reported in the literature. The results warrant further testing in a prospective way in a larger cohort.

C/EBPß Is a Transcriptional Regulator of Wee1 at the G2/M Phase of the Cell Cycle.

The CCAAT/enhancer-binding protein ß (C/EBPß) is a transcription factor that regulates cellular proliferation, differentiation, apoptosis and tumorigenesis. Although the pro-oncogenic roles of C/EBPß have been implicated in various human cancers, how it contributes to tumorigenesis or tumor progression has not been determined. Immunohistochemistry with human non-small cell lung cancer (NSCLC) tissues revealed that higher levels of C/EBPß protein were expressed compared to normal lung tissues. Knockdown of C/EBPß by siRNA reduced the proliferative capacity of NSCLC cells by delaying the G2/M transition in the cell cycle. In C/EBPß-knockdown cells, a prolonged increase in phosphorylation of cyclin dependent kinase 1 at tyrosine 15 (Y15-pCDK1) was displayed with simultaneously increased Wee1 and decreased Cdc25B expression. Chromatin immunoprecipitation (ChIP) analysis showed that C/EBPß bound to distal promoter regions of WEE1 and repressed WEE1 transcription through its interaction with histone deacetylase 2. Treatment of C/EBPß-knockdown cells with a Wee1 inhibitor induced a decrease in Y15-pCDK1 and recovered cells from G2/M arrest. In the xenograft tumors, the depletion of C/EBPß significantly reduced tumor growth. Taken together, these results indicate that Wee1 is a novel transcription target of C/EBPß that is required for the G2/M phase of cell cycle progression, ultimately regulating proliferation of NSCLC cells.

Upregulation of transforming growth factor-beta type I receptor by interferon consensus sequence-binding protein in osteosarcoma cells.

Transforming growth factor-beta (TGF-ß) is a known tumor suppressor, which also exerts a tumor promoting activity at an advanced stage of cancer. Previously, we reported that expression of interferon consensus sequence-binding protein (ICSBP), also known as interferon regulatory factor-8, is positively correlated with TGF-ß type I receptor (TGF-ß RI) expression in osteosarcoma patient tissues. In this study, we demonstrated that ICSBP upregulated TGF-ß RI and induced epithelial-to-mesenchymal transition-like phenomena in human osteosarcoma cell lines. As determined by soft agar growth of osteosarcoma cells and xenografted mouse models, ICSBP increased tumorigenicity, which was reversed by ICSBP knock-down or a TGF-ß RI inhibitor. To test whether ICSBP directly regulates the promoter activity of TGF-ß RI, we performed a TGF-ß RI promoter assay, an electro mobility shift assay, and a chromatin immunoprecipitation assay. We observed that TGF-ß RI promoter was activated in ICSBP-overexpressing osteosarcoma cells. Exploiting serial deletions and mutations of the TGF-ß RI promoter, we found a putative ICSBP-binding site at nucleotides -216/-211 (GGXXTC) in the TGF-ß RI promoter. Our data suggest that ICSBP upregulates TGF-ß RI expression by binding to this site, causing ICSBP-mediated tumor progression in osteosarcoma cells. In addition, we found a positive correlation between ICSBP and TGF-ß RI expression in several types of tumors using the cBioportal database. SUMMARY: We demonstrated that interferon consensus sequence-binding protein upregulates transforming growth factor-beta type I receptor (TGF-ß RI) expression by binding to nucleotides -216/-211 (GGXXTC) in the TGF-ß RI promoter, which resulted in increased tumorigenicity and tumor progression in human osteosarcoma cells.

Thromboembolism in children with cancer: a retrospective multicenter study in Korea.

Thromboembolism (TE) is a major cause of morbidity and mortality in adult cancer patients; however, there is a lack of sufficient knowledge on TE in pediatric cancer patients. We aimed to determine the epidemiology of TE in Korean children with cancer. Between January 2000 and July 2015, we retrospectively analyzed pediatric patients newly diagnosed with cancer at six tertiary hospitals in Korea. Of 3611 children with cancer, 33 (0.91%) had TE. A higher number of patients with acute lymphoblastic leukemia (n = 13), brain tumors (n = 6), lymphoma (n = 4), and bone/soft tissue sarcomas (n = 5) tended to develop TE. The male/female ratio was 17/16, and the median age at TE diagnosis was 10 years and 2 months. TE was detected a median of 2 months after cancer diagnosis. Symptoms including pain and swelling were present in 18 of the 33 patients. In terms of location, three intracerebral, 23 upper venous, six lower venous and one combined upper and lower venous system TEs were observed. Additional risk factors for TE included central venous catheter (CVC) use in 12 patients, steroid and/or L-asparaginase use in nine, and CVC and steroid and/or L-asparaginase use in seven. The TE incidence rate was quite low among Korean children with cancer, but higher than in the general pediatric population and among children hospitalized for diseases other than cancer. Further investigation of a larger pool of patients is warranted to determine the most effective strategies to prevent and treat TE in Korean children with cancer.

A Nationwide, Population-Based Epidemiologic Study of Childhood Brain Tumors in Korea, 2005-2014: A Comparison with United States Data.

BACKGROUND: We investigated the epidemiologic characteristics of childhood brain tumors (CBT) in Korea, and compared our findings with those from the United States. METHODS: We searched the Korea National Cancer Incidence Database of the Korea Central Cancer Registry (KCCR) from 2005 to 2014, which included all Korean patients with CBT aged 0 to 19 years at diagnosis. The age-standardized incidence rates (ASR) and the 5-year relative survival rate (RSR) were determined. The Central Brain Tumor Registry of the United States (CBTRUS) classification and definitions were applied to allow direct comparison with U.S. RESULTS: A total of 6,027 CBTs were identified. The ASR of all CBTs was 5.08 per 100,000 population, which was significantly lower than that in the United States (5.57). However, the ASR of nonmalignant CBTs in Korea (2.48) was significantly higher than that in the United States (2.15). Embryonal tumors (ASR: 0.99 and 0.72 in the 0-4 and 5-9 year age groups, respectively) were the most common CBTs in these respective age groups. Germ cell tumors (0.78) and pituitary tumors (1.63) were the most common CBTs in the 10-14 and 15-19 year age groups, respectively. The 5-year RSR of CBTs was 84% and varied according to histology. CONCLUSIONS: High incidences of nonmalignant and germ cell tumors are distinct CBT features in Korean children and adolescents. IMPACT: To our knowledge, this is the first and largest population-based epidemiologic study of CBTs in Asia. Our findings support the notion that East Asian populations have a higher incidence of central nervous system germ cell tumors than other races.

Second malignant neoplasms after childhood cancer: A nationwide population-based study in Korea.

BACKGROUND: Second malignant neoplasm is one of the most devastating late effects of childhood cancers. This study aimed to evaluate the incidence and survival outcomes of patients developing second malignant neoplasms (SMNs) after surviving childhood cancer in Korea. METHODS: Medical data of childhood cancer patients diagnosed between 1993 and 2012 were obtained from the Korea Central Cancer Registry. The risk of developing SMNs was calculated using standardized incidence ratio (SIR), excess absolute risk (EAR), and cumulative risk. Kaplan-Meier survival curves were estimated, stratified by SMN status. RESULTS: A total of 28,405 childhood cancer patients were diagnosed in the study period, and 337 (1.2%) developed SMN. The total follow-up period was 197,359 person-years at risk (PYR), with a median follow-up duration of 5.6 years. Overall SIR was 20.0, which was 23.2 in women, and 17.6 in men. The overall EAR was 16.4 per 10,000 PYR. The most common types of SMNs, in order of incidence, were other malignant epithelial neoplasms, leukemia, and soft tissue sarcomas. The cumulative incidence of developing SMNs was 0.7% at 5 years, 1.2% at 10 years, and 2% at 15 years. After primary cancer diagnosis, the 10-year overall survival rate of patients with SMNs was 65.1%, which was lower than the 73.4% in patients without SMN. After SMN diagnosis, the 10-year overall survival rate was 55.8%. CONCLUSION: Through this registry-based study of 5.6 years of follow up, childhood cancer survivors were found to be at 20-fold higher risk of developing a malignant neoplasm compared to the general population. The majority of malignant neoplasms are malignant epithelial neoplasms, leukemia, and soft tissue sarcomas. Continued surveillance for assessing long-term risks, and guidance for appropriate long-term follow up of childhood cancer survivors, are needed.

School performance of childhood cancer survivors in Korea: A multi-institutional study on behalf of the Korean Society of Pediatric Hematology and Oncology.

OBJECTIVE: To investigate school performance of childhood cancer survivors focusing on the child's functioning, including peer relationships, school attendance, and academic achievement. METHODS: We studied 241 children from 15 institutions in Korea between 2015 and 2016. The self-reported paper-and-pencil questionnaires were used. RESULTS: Approximately 22% of the survivors suffered from lack of friends. Bullying was reported by 30% of survivors. Survivors who returned to primary school reported a higher incidence of bullying compared with survivors who returned to middle or high school (P = 0.03). The percentage of children who missed classes more than 4 days in a month was higher in survivors with brain tumors than those with other tumors (P = 0.04). Approximately 41% of children reported learning difficulty. After returning to school, 53% of the patients reported that they had lower overall mark averages than they had before. Patients who returned to high school showed the highest rate of repeating a grade and the lowest rate of achieving high academic marks. The school marks in the Korean (P = 0.03), English (P = 0.04), and physical education (P = 0.04) were worse for the children with brain tumors than for the children with other tumors. CONCLUSION: We found that 20% to 25% of survivors experienced peer-related difficulties upon returning to school. Patients who return to school, especially high school, should be provided more educational support to overcome low academic achievement. Particular concern is needed to the patients with brain tumors, who are at risk for significant academic and social difficulties and therefore may require more intensive support in school.

Nationwide Statistical Analysis of Lymphoid Malignancies in Korea.

PURPOSE: Regional differences in the incidence of lymphoid malignancies have been reported worldwide, but there has been no large-scale epidemiologic analysis in Korea. The aim of this study was to provide a nationwide population-based statistical analysis of Korean patients with lymphoid malignancies. MATERIALS AND METHODS: The Korea Central Cancer Registry analyzed the incidence and survival of patients with lymphoid malignancies from the Korean National Cancer Incidence Database. Diseases were grouped by clinically relevant categories based on the 2008 World Health Organization classification. RESULTS: Overall 65,948 lymphoid diseases were identified between 1999 and 2012. The incidence of most subtypes increased with age, except for precursor cell neoplasms. Male predominance (male:female ratio=1.28:1) was observed. In 2012, annual age-standardized incidence rates per 100,000 persons of Hodgkin's lymphoma, mature B-cell neoplasm, mature T/natural killer (NK)-cell neoplasm, and precursor cell neoplasm were 0.46, 6.60, 0.95, and 1.50, respectively, and they increased yearly from 1999. Composite Hodgkin's and non-Hodgkin's lymphomas were extremely rare. Survival improvement estimated using 5-year relative survival rate was observed in patients with Hodgkin's lymphoma (71.1%-83.0%), diffuse large B-cell lymphoma (49.5%-61.5%), plasma cell neoplasms (20.2%-36.9%), and lymphoblastic lymphoma/leukemia (41.5%-56.3%) between 1993 and 2012. However, survival rates of T/NK-cell lymphoma (excluding cutaneous T-cell lymphoma) ranged from 40.5%-43.5% during the study period. Survival rates decreased with age in most subtypes. CONCLUSION: This report presented the subtype-specific statistical analysis of lymphoid malignancies in the Korean population, showing increasing incidences and survival rates in most subtypes.