Establishment and characterization of a novel MDM2/MYCN-co-amplified neuroblastoma cell line, NBN-SHIM, established from a late recurrent stage MS tumor.

The biological heterogeneity of neuroblastoma underscores the need for an in vitro model of each molecularly defined subgroup to investigate tumorigenesis and develop targeted therapies. We have established a permanently growing cell line from a 12-year-old girl who developed a late recurrent stage MS, MDM2-amplified neuroblastoma arising in the liver and performed histological, molecular, cytogenetic, exome, and telomere analyses of the recurrent tumor and the cell line. On histology, the recurrent tumor was immunoreactive for TP53, CDKN1A, and MDM2. A molecular cytogenetic study of the recurrent tumor revealed the amplification of MDM2 but no amplification of MYCN. The established cell line, NBM-SHIM, showed amplification of both MDM2 and MYCN on double-minute chromosomes. A copy number evaluation based on exome data confirmed the finding for MYCN and MDM2 and further identified high ploidy on CDK4 and GLI2 loci in the recurrent tumor and the cell line. The telomere maintenance mechanism on the cell line is unusual in terms of the low expression of TERT despite MYCN amplification and alternative lengthening of telomeres suggested by positive value for C-circle assay and telomere contents quantitative assay. The cell line is unique because it was established from a MYCN-nonamplified, MDM2-amplified, late-relapsed stage MS neuroblastoma, and MYCN amplification was acquired during cell culture. Therefore, the cell line is a valuable tool for investigating neuroblastoma tumorigenesis and new molecular targeted therapies for disrupted ARF-TP53-MDM2 pathway and amplification of MDM2 and CDK4.

Localized anaplastic lymphoma kinase-positive histiocytosis in a cerebellar hemisphere with long-term treatment: illustrative case.

BACKGROUND: Anaplastic lymphoma kinase (ALK)-positive histiocytosis (ALK-H) is an emerging entity in the category of histiocytic neoplasms that was first reported as a multisystemic disease in three infants in 2008. The clinicopathological spectrum of ALK-H has been expanded to include localized disorders in specific organs, but the features of this subtype are not well known. The authors report a case of ALK-H localized in the central nervous system that was difficult to treat and review the relevant literature. OBSERVATIONS: The authors reviewed archival histiocytic tumors at their institute and found a pediatric case of ALK-H localized in a cerebellar hemisphere that had previously been reported as histiocytic sarcoma. Chemotherapy (approximately 1 year), additional surgery, and conventional chemotherapy (approximately 2.5 years) led to clinical remission, and maintenance chemotherapy was continued (approximately 1.5 years). Three years after completing treatment, a high-grade glioma was found in a cerebral hemisphere, and the patient died of the glioma 2 years later. LESSONS: Although the prognosis of ALK-H is generally good according to prior cases, the authors' case required long-term conventional chemotherapy, suggesting the tumor displayed aggressive characteristics. Early administration of ALK inhibitors may be necessary.

Metronomic Chemotherapy for Pediatric Refractory Solid Tumors: A Retrospective Single-center Study.

Metronomic chemotherapy (MC) is based on chronic administration of chemotherapeutic agents at minimally toxic doses without prolonged drug-free breaks, that inhibits tumor angiogenesis and induces tumor dormancy. This study aimed to determine the efficacy of MC for pediatric refractory solid tumors. We retrospectively analyzed the data of pediatric patients with relapsed/refractory solid tumors who received treatment, including low-dose continuous administration of anticancer drugs, at our institute. Of the 18 patients, the disease statuses at the initiation of MC were complete remission (n=2), partial remission/stable disease (n=5), and progressive disease (n=11). The overall survival rate was 61% at 12 months and 34% at 24 months, and the progression-free survival rate was 21% at 12 and 24 months. Although only 5 of the 18 patients showed certain tumor regression or maintained remission, tumors that stabilized, maintained remission/stable disease, and showed certain advantages in terms of overall survival rate, even if limited to progressive disease. Approximately half of the patients demonstrated temporal tumor stabilization and improved survival time. Overall, previous reports and the present study support the conclusion that MC has the potential to play an important role in pediatric cancer treatment during the advanced stage.

Consensus classification of pediatric hepatocellular tumors: A report from the Children's Hepatic tumors International Collaboration (CHIC).

BACKGROUND: Liver tumors are rare in children with histologic heterogeneity that makes diagnosis challenging. Systematic histopathological review, performed as part of collaborative therapeutic protocols, identified relevant histologic subtypes that are important to distinguish. The Children's Hepatic tumors International Collaboration (CHIC) was established to study pediatric liver tumors on a global scale and led to establishment of a provisional consensus classification for use in international clinical trials. The current study is the validation of this initial classification and first large-scale application by international expert reviewers. PROCEDURE: The CHIC initiative includes data from 1605 children treated on eight multicenter hepatoblastoma (HB) trials. Review of 605 available tumors was performed by seven expert pathologists from three consortia (US, EU, Japan). Cases with discordant diagnoses were collectively reviewed to reach a final consensus diagnosis. RESULTS: Of 599 cases with sufficient material for review, 570 (95.2%) were classified as HB by all consortia, and 29 (4.8%) as non-HB, which included "hepatocellular neoplasm, NOS" and malignant rhabdoid tumors. 453 of 570 HBs were classified as epithelial by final consensus. Some patterns (i.e., small cell undifferentiated, macrotrabecular, cholangioblastic) were selectively identified by reviewers from different consortia. All consortia identified a similar number of mixed epithelial-mesenchymal HB. CONCLUSIONS: This study represents the first large-scale application and validation of the pediatric malignant hepatocellular tumors consensus classification. It is a valuable resource to train future generations of investigators on accurate diagnosis of these rare tumors and provides a framework for further international collaborative studies and refinement of the current classification of pediatric liver tumors.

Outcomes of Patients Treated for Hepatoblastoma with Low Alpha-Fetoprotein and/or Small Cell Undifferentiated Histology: A Report from the Children's Hepatic Tumors International Collaboration (CHIC).

Small cell undifferentiated (SCU) histology and alpha-fetoprotein (AFP) levels below 100 ng/mL have been reported as poor prognostic factors in hepatoblastoma (HB); subsequent studies reported SMARCB1 mutations in some SCU HBs confirming the diagnosis of rhabdoid tumor. The Children's Hepatic tumors International Collaboration (CHIC) database was queried for patients with HB who had AFP levels less than 100 ng/mL at diagnosis or were historically diagnosed as SCU HBs. Seventy-three of 1605 patients in the CHIC database were originally identified as SCU HB, HB with SCU component, or HB with low AFP levels. Upon retrospective review, they were re-classified as rhabdoid tumors (n = 11), HB with SCU component (n = 41), and HB with low AFP (n = 14). Seven were excluded for erroneously low AFP levels. Overall survival was 0% for patients with rhabdoid tumors, 76% for patients with HB with SCU component, and 64% for patients with HB with AFP less than 100 ng/mL. Patients with HB with SCU component or low AFP should be assessed for SMARCB1 mutations and, if confirmed, treated as rhabdoid tumors. When rhabdoid tumors are excluded, the presence of SCU component and low AFP at diagnosis were not associated with poor prognosis in patients diagnosed with HB.

Infantile hepatic hemangioma and hepatic mesenchymal hamartoma in an infant associated with placental mesenchymal dysplasia: a case report.

BACKGROUND: Although infantile hepatic hemangioma and hepatic mesenchymal hamartoma are relatively common in benign pediatric liver tumors, coexistence of the two tumors is rare. Placental mesenchymal dysplasia is also a rare disorder. We report the case of a baby girl born after a pregnancy complicated by placental mesenchymal dysplasia, who developed both infantile hepatic hemangioma and hepatic mesenchymal hamartoma. CASE PRESENTATION: The patient was born at 32 weeks and 5 days of gestation for impending placental abruption, weighing 1450 g. Liver tumors, composed of both hypervascular solid and large cystic lesions, were detected after birth and markedly increased to create abdominal distention within 9 months. Diagnostic imaging suspected the coexistence of infantile hepatic hemangioma and cystic hepatic mesenchymal hamartoma. Following propranolol therapy for infantile hepatic hemangioma and needle puncture of a large cyst, the cystic lesions and adjacent hypervascular lesions were partially resected via laparotomy. Pathological findings confirmed the coexistence of hepatic mesenchymal hamartoma and infantile hepatic hemangioma, which had no association with androgenetic/biparental mosaicism. The postoperative course was uneventful, and the tumor had not regrown after 3 years. CONCLUSIONS: Although the coexistence of infantile hepatic hemangioma and hepatic mesenchymal hamartoma associated with placental mesenchymal dysplasia is extremely rare, the pathological and pathogenetic similarities between these disorders suggest that they could have derived from similar embryologic origins rather than being a mere coincidence. Further follow-up is required, with careful attention to the potential for malignant hepatic mesenchymal hamartoma transformation.

A novel risk stratification model based on the Children's Hepatic Tumours International Collaboration-Hepatoblastoma Stratification and deoxyribonucleic acid methylation analysis for hepatoblastoma.

INTRODUCTION: Hepatoblastoma (HB) is the most common paediatric liver tumour, and epigenetic aberrations may be important in HB development. Recently, the Children's Hepatic Tumors International Collaboration-Hepatoblastoma Stratification (CHIC-HS) developed risk stratification based on clinicopathological factors. This study aimed to construct a more accurate model by integrating CHIC-HS with molecular factors based on DNA methylation. METHODS: HB tumour specimens (N = 132) from patients treated with the Japanese Pediatric Liver Tumors Group-2 protocol were collected and subjected to methylation analysis by bisulfite pyrosequencing. Associations between methylation status and clinicopathological factors, overall survival (OS), and event-free survival (EFS) were retrospectively analysed. We investigated the effectiveness of the evaluation of methylation status in each CHIC-HS risk group and generated a new risk stratification model. RESULTS: Most specimens (82%) were from post-chemotherapy tissue. Hypermethylation in ≥2 of the four genes (RASSF1A, PARP6, OCIAD2, and MST1R) was significantly associated with poorer OS and EFS. Multivariate analysis indicated that ≥2 methylated genes was an independent prognostic factor (hazard ratios of 6.014 and 3.684 for OS and EFS, respectively). Two or more methylated genes was also associated with poorer OS in the CHIC-very low (VL)-/low (L)-risk and CHIC-intermediate (I) risk groups (3-year OS rates were 83% vs. 98% and 50% vs. 95%, respectively). The 3-year OS rates of the VL/L, I, and high-risk groups in the new stratification model were 98%, 90%, and 62% (vs. CHIC-HS [96%, 82%, and 65%, respectively]), optimising CHIC-HS. CONCLUSIONS: Our proposed stratification system considers individual risk in HB and may improve patient clinical management.

A patient with very early onset FH-deficient renal cell carcinoma diagnosed at age seven.

Hereditary leiomyomatosis and renal cell cancer (HLRCC) is caused by heterozygous germline variants in the fumarate hydratase (FH) gene and is associated with increased susceptibility to cutaneous leiomyomas, uterine leiomyomas, and renal cell carcinoma (RCC). HLRCC-associated RCC usually occurs in the middle age, with the median age being 40-44 years. This report describes a seven-year-old (84-month-old) male who developed a large right kidney tumor with multiple cystic lesions that contained enhanced solid components. There was no evidence of distant metastasis. The male patient underwent right nephrectomy and has been recovering well without metastasis or recurrence. Pathological examination revealed that tumor cells with relatively prominent nucleoli and surrounded by halos, were located in a limited area. Immunohistochemical staining was negative for FH. Whole-exome sequencing identified his germline variant in the FH gene and its loss of heterozygosity in the tumor. At nine years (114 months) of age, the male patient showed no recurrence of the tumor. This was the youngest-onset case of HLRCC-associated RCC to date. This report may affect the starting age for future RCC-surveillance programs for patients with HLRCC.

Feasibility of dose-dense cisplatin-based chemotherapy in Japanese children with high-risk hepatoblastoma: Analysis of the JPLT3-H pilot study.

BACKGROUND: The SIOPEL-4 study has demonstrated that dose-dense cisplatin-based chemotherapy dramatically improves outcome in children with high-risk hepatoblastoma in western countries. However, the feasibility and safety of this regimen have not been clarified in Japanese patients. METHODS: A pilot study, JPLT3-H, was designed to evaluate the safety profile of the SIOPEL-4 regimen in Japanese children with newly diagnosed hepatoblastoma with either metastatic disease or low alpha-fetoprotein. RESULTS: A total of 15 patients (three female) were enrolled. Median age was 2 years (range, 0-14). Three patients were PRETEXT II (where PRETEXT is PRETreatment EXTent of disease), six PRETEXT III, and six PRETEXT IV. All patients had lung metastasis, none had low alpha-fetoprotein. Eight patients completed the prescribed treatment, and seven patients discontinued therapy prematurely, four due to progressive disease and three due to causes other than severe toxicity. Grade 4 neutropenia was documented in most patients in preoperative cycles A1-3 (11/15 in A1, 9/11 in A2, and 7/11 in A3) and in all considering all cycles. Grade 3-4 thrombocytopenia and grade 3 anemia were also frequently observed. Patients experienced several episodes of grade 3 febrile neutropenia, but none had grade 4 febrile neutropenia or severe infections. One patient had grade 3 heart failure only in the first cycle. Other grade 3 or 4 toxicities were hypomagnesemia, anorexia, nausea, mucositis, liver enzyme elevation, fever, infection, and fatigue. There were no unexpected severe toxicities. CONCLUSION: The toxicity profile of JPLT3-H was comparable to that of SIOPEL-4. Dose-dense cisplatin-based chemotherapy may be feasible among Japanese patients with high-risk hepatoblastoma.

Using the in vitro drug sensitivity test to identify candidate treatments for transient abnormal myelopoiesis.

Approximately 20% of patients with transient abnormal myelopoiesis (TAM) die due to hepatic or multiorgan failure. To identify potential new treatments for TAM, we performed in vitro drug sensitivity testing (DST) using the peripheral blood samples of eight patients with TAM. DST screened 41 agents for cytotoxic properties against TAM blasts. Compared with the reference samples of healthy subjects, TAM blasts were more sensitive to glucocorticoids, the mitogen-activated protein kinase kinase (MAP2K) inhibitor trametinib, and cytarabine. Our present results support the therapeutic potential of glucocorticoids and the role of the RAS/MAP2K signalling pathway in TAM pathogenesis.

Clinicopathological study of surgery for pulmonary metastases of hepatoblastoma with indocyanine green fluorescent imaging.

BACKGROUND: The prognosis of metastatic hepatoblastoma remains poor; to improve it, pulmonary metastasis must be controlled. Indocyanine green (ICG) fluorescent imaging has been used recently for lung metastasectomy. The objective of our study was to clarify the usefulness of ICG imaging for lung metastasectomy of hepatoblastoma using detailed clinicopathological analysis. PROCEDURE: Patients with hepatoblastoma who underwent resection of pulmonary metastases with ICG fluorescent imaging were studied using a retrospective analysis of clinical information, a review of their surgical records, and a histological analysis of their metastatic nodules. RESULTS: Sixteen patients were enrolled. In total, 61 ICG imaging-guided pulmonary metastasectomies were performed, and 350 ICG-positive and 23 ICG-negative specimens were identified. Tumors were confirmed in 250 of the ICG-positive specimens, including eight nonpalpable nodules, on microscopic examination. ICG-positive and tumor-negative specimens showed histological changes suggesting the regression of a tumor or bloodstream disturbance. CONCLUSIONS: Surgical resection is one of the few treatment strategies available to patients with hepatoblastoma with multiple relapses of pulmonary metastasis resistant to chemotherapy. This study demonstrates the high sensitivity of ICG imaging and that thorough metastasectomy can be achieved with ICG imaging. Because a number of false-positive specimens were detected, further optimization of the dose of ICG and the timing of its administration, and establishment of detection of ICG-positive, tumor-negative nodules during surgery are important issues. Several false-negative specimens were also detected, suggesting the presence of ICG-negative metastatic tumors. Palpation during surgery and imaging studies remain essential for detecting metastatic lesions, even in the era of ICG imaging.

Genetic and epigenetic basis of hepatoblastoma diversity.

Hepatoblastoma (HB) is the most common pediatric liver malignancy; however, hereditary predisposition and acquired molecular aberrations related to HB clinicopathological diversity are not well understood. Here, we perform an integrative genomic profiling of 163 pediatric liver tumors (154 HBs and nine hepatocellular carcinomas) based on the data acquired from a cohort study (JPLT-2). The total number of somatic mutations is precious low (0.52/Mb on exonic regions) but correlated with age at diagnosis. Telomerase reverse transcriptase (TERT) promoter mutations are prevalent in the tween HBs, selective in the transitional liver cell tumor (TLCT, > 8 years old). DNA methylation profiling reveals that classical HBs are characterized by the specific hypomethylated enhancers, which are enriched with binding sites for ASCL2, a regulatory transcription factor for definitive endoderm in Wnt-pathway. Prolonged upregulation of ASCL2, as well as fetal-liver-like methylation patterns of IGF2 promoters, suggests their "cell of origin" derived from the premature hepatoblast, similar to intestinal epithelial cells, which are highly proliferative. Systematic molecular profiling of HB is a promising approach for understanding the epigenetic drivers of hepatoblast carcinogenesis and deriving clues for risk stratification.

Frequent breakpoints of focal deletion and uniparental disomy in 22q11.1 or 11.2 segmental duplication region reveal distinct tumorigenesis in rhabdoid tumor of the kidney.

SMARCB1 is mutated in most rhabdoid tumors (RTs) developing in the kidney (RTK) and various other organs. Focal deletions found in patients with 22q11.2 deletion syndrome show breakpoints within clusters of segmental duplications (SDs), and those in some RTs show breakpoints in the 22q11-q12 region. SDs are known to cause focal deletion mediated by non-allelic homologous recombination. The present study identified SMARCB1 alterations in all 30 RTKs, using SNP array CGH, MLPA, and sequence analyses. Twenty-eight tumors had a total of 51 breakpoints forming focal 22q deletion and/or uniparental disomy (22qUPD), and the other two had compound mutation with no breakpoints in 22q. Twenty-four (47.1%) of the 51 breakpoints were within SDs, and occurred in 16 (53.3%) of the 30 tumors. The association of breakpoints with SDs was found not only in focal deletion, but also in 22qUPD, indicating that SDs mediate the first and second hits (focal deletion) and the second hit (22qUPD) of SMARCB1 alteration. Of the 51 breakpoints, 14 were recurrent, and 10 of the 14 were within SDs, suggesting the presence of hotspots in the 22q11.2 region. One recurrent breakpoint outside SDs resided in SMARCB1, suggesting inactivation of the gene by out-of-frame fusion. The association between SDs and focal deletion has been reported in two other types of cancer. RTKs may be the third example of SD-associated tumors. Thus, the present study indicated that RTKs exploit genomic instability in the 22q11.1-11.2 SDs region, and 22qUPD caused by mitotic recombination may also be mediated by SDs.

Distinct clonal evolution in a case with anaplastic embryonal rhabdomyosarcoma.

BACKGROUND: Clonal evolution of malignancy is a complex process related to intratumoral heterogeneity, as recent studies have also demonstrated in rhabdomyosarcoma. The purpose of this study is to present a distinct clonal feature of a case with anaplastic embryonal type rhabdomyosarcoma (ERMS) using molecular analysis. METHODS: A five-year-old girl developed a metastatic pelvic tumor. We cultured neoplastic cells isolated from the biopsy sample. Next, to characterize the current case, we analyzed the biopsy sample, autopsy sample, and established cell line using combined modalities, including histopathological, cytogenetic, and molecular assay. We also undertook the backtrack mutation-specific polymerase chain reaction to reveal clonal composition. RESULTS: The histology of the biopsy sample was consistent with ERMS with focal anaplasia. We established a permanently growing cell line, ICH-ERMS-1, from the biopsy sample. On molecular analysis, the biopsied tissue revealed a missense mutation at codon 245 of TP53. In contrast, the autopsy tumor tissue and the cell line established from the biopsied tissue showed a missense mutation at codon 248. A backtrack study using mutation-specific polymerase chain reaction detected a TP53 codon 248 mutation in the original biopsy sample. All the specimens examined had a missense mutation at PTPN11 codon 69. CONCLUSIONS: This study highlights intratumoral heterogeneity and distinct clonal change related to the functional context in our anaplastic ERMS case, supporting the concept of intratumoral heterogeneity and clonal evolution. It requires further case collection to reveal whether p14ARF-p53-MDM2 tumor suppressor pathway alteration, considered a late event in ERMS tumorigenesis, is responsible for anaplasia in ERMS.

A MicroRNA Cluster in the DLK1-DIO3 Imprinted Region on Chromosome 14q32.2 Is Dysregulated in Metastatic Hepatoblastomas.

Hepatoblastoma (HB) is the most common malignant liver neoplasm in children. Despite progress in HB therapy, outcomes for patients with metastatic disease remain poor. Dysregulation of miRNA expression is one of the potential epigenetic mechanisms associated with pathogenesis of HB. However, miRNA profiles related to the different stages of HB tissues and cells, in particular of lung metastatic tumor cells, are unknown. In the present study, using array-based miRNA expression and DNA methylation analysis on formalin-fixed paraffin-embedded tissues, we aimed to identify miRNA changes that can discriminate between lung metastatic tumors, primary tumors (fetal and embryonal subtypes), and nontumorous surrounding livers. Our analysis demonstrated that a large cluster of microRNAs and snoRNAs located within the 14q32.2 DLK1-DIO3 region showed a strikingly upregulated expression pattern in HB tumors, especially metastatic tumors, compared to normal liver tissues. This revealed dysregulation of miRNAs similar to that seen in a malignant stem-like subtype of hepatocellular carcinoma associated with poor prognosis. These findings in HB mirror similar findings made in multiple other cancer types. With further analysis this may in future allow stratification of different stages and types of HB tumors based on their miRNA profiles, which could lead to new approaches to diagnosis and treatment in progressive HB patients.

Intraoral Approach for a Congenital Teratoma in the Orbit Extending into the Pterygopalatine Fossa.

This article reports an intraoral approach for a congenital mature teratoma in the orbit, extending into the pterygopalatine fossa and the zygoma remodeling due to biological and functional matrix theory during the neonatal period. The operation took place on the 56th postnatal day due to gradual proptosis of the left eye from the socket. The entire orbital tumor could be surgically removed via the inferior orbital fissure, which had been expanded by the pressure of the tumor. This case suggests that orbital tumors expanding into pterygopalatine fossa can be removed by the intraoral approach because the bone of infants is so soft. The eyeball of the patient was temporarily depressed after the operation, but that was improved by tissue remodeling with time. Therefore, it is recommended that reconstructive surgery for an infant should be performed at the age of 12 months or older.

Comprehensive genetic analysis of pediatric germ cell tumors identifies potential drug targets.

To elucidate the molecular pathogenesis of pediatric germ cell tumors (GCTs), we performed DNA methylation array analysis, whole transcriptome sequencing, targeted capture sequencing, and single-nucleotide polymorphism array analysis using 51 GCT samples (25 female, 26 male), including 6 germinomas, 2 embryonal carcinomas, 4 immature teratomas, 3 mature teratomas, 30 yolk sac tumors, and 6 mixed germ cell tumors. Among the 51 samples, 11 were from infants, 23 were from young children, and 17 were from those aged ≥10 years. Sixteen of the 51 samples developed in the extragonadal regions. Germinomas showed upregulation of pluripotent genes and global hypomethylation. Pluripotent genes were also highly expressed in embryonal carcinomas. These genes may play essential roles in embryonal carcinomas given that their binding sites are hypomethylated. Yolk sac tumors exhibited overexpression of endodermal genes, such as GATA6 and FOXA2, the binding sites of which were hypomethylated. Interestingly, infant yolk sac tumors had different DNA methylation patterns from those observed in older children. Teratomas had higher expression of ectodermal genes, suggesting a tridermal nature. Based on our results, we suggest that KIT, TNFRSF8, and ERBB4 may be suitable targets for the treatment of germinoma, embryonal carcinomas, and yolk sac tumors, respectively.

Pilot study of the combination of sorafenib and fractionated irinotecan in pediatric relapse/refractory hepatic cancer (FINEX pilot study).

BACKGROUND: Preclinical observations suggested a synergistic effect of sorafenib (SFN) and irinotecan (CPT-11) in hepatoblastoma (HB). Thus, we conducted a feasibility study of fractionated CPT-11 combined with SFN to develop a new therapy against relapsed/refractory pediatric hepatic cancer (HC). PROCEDURE: The study was originally designed as a phase I, standard 3+3 dose-finding study to evaluate dose-limiting toxicities (DLTs) for the regimen and the optimal CPT-11 dose in combination with SFN against relapsed/refractory pediatric HC, including HB and hepatocellular carcinoma (HCC). The enrolled patients received SFN at 200 mg/m2 every 12 hours or 400 mg/m2 every 24 hours daily combined with CPT-11 at 20 mg/m2 /day on days 1 to 5 as an initial level 1 dose. RESULTS: Six patients with HB (n = 4) or HCC (n = 2) were enrolled and treated with CPT-11 dose level 1. The median age at enrollment was 8.7 (6.2-16.3) years. All patients received platinum-containing chemotherapy, and five or two patients received CPT-11 or SFN before enrollment, respectively. Regimen toxicities were evaluable in all patients. One of six patients experienced a grade 4 transaminase levels increase, which was defined as a DLT per protocol. Grade 3/4 neutropenia and a grade 3 transaminase level increase occurred in three patients and one patient, respectively. All patients reported grade 1/2 toxicities such as anemia, skin toxicity, gastrointestinal symptoms, and hypoalbuminemia. CONCLUSIONS: Although the study was terminated before determining the maximum-tolerated CPT-11 dose, SFN and CPT-11 at the level 1 dose were concluded to be tolerable in pediatric patients with HC.

Integrated multiomics analysis of hepatoblastoma unravels its heterogeneity and provides novel druggable targets.

Although hepatoblastoma is the most common pediatric liver cancer, its genetic heterogeneity and therapeutic targets are not well elucidated. Therefore, we conducted a multiomics analysis, including mutatome, DNA methylome, and transcriptome analyses, of 59 hepatoblastoma samples. Based on DNA methylation patterns, hepatoblastoma was classified into three clusters exhibiting remarkable correlation with clinical, histological, and genetic features. Cluster F was largely composed of cases with fetal histology and good outcomes, whereas clusters E1 and E2 corresponded primarily to embryonal/combined histology and poor outcomes. E1 and E2, albeit distinguishable by different patient age distributions, were genetically characterized by hypermethylation of the HNF4A/CEBPA-binding regions, fetal liver-like expression patterns, upregulation of the cell cycle pathway, and overexpression of NQO1 and ODC1. Inhibition of NQO1 and ODC1 in hepatoblastoma cells induced chemosensitization and growth suppression, respectively. Our results provide a comprehensive description of the molecular basis of hepatoblastoma and rational therapeutic strategies for high-risk cases.

Parathyroid carcinoma in a 13-year-old girl with a long-term survival.

BACKGROUND: Parathyroid carcinoma as a cause of primary hyperparathyroidism in children is extremely rare. We report a case of parathyroid carcinoma which occurred in a 13-year-old girl who survived for more than 45 years after the first operation. CASE PRESENTATION: A woman was admitted to our hospital for the treatment of recurrent parathyroid carcinoma in the neck. She had been diagnosed with primary hyperparathyroidism from a fibula fracture and underwent parathyroidectomy at 13 years old. She had no family history of multiple endocrine neoplasia or jaw tumor syndrome. Genetic testing was not performed, and the histopathological diagnosis of the tumor had been parathyroid adenoma at the time. At 22 years old, she showed hypercalcemia after a femur fracture. Pulmonary metastases of parathyroid carcinoma in the bilateral lungs were found and surgically removed. Regarding the clinical course, her diagnosis was corrected from parathyroid adenoma to parathyroid carcinoma. At 33 years old, re-resection of the lung metastases was performed. For 10 years, her serum calcium level stayed within the normal range. However, her serum calcium level and intact parathyroid hormone eventually began to increase. Two masses suspected of being parathyroid carcinoma recurrence were found in the neck when she was 57 years old. En bloc resection was performed. Pathologically, the tumors were diagnosed as parathyroid adenoma. The serum calcium level and intact parathyroid hormone did not decrease after the operation. A 99mTc-methoxy-isobutyl-isonitrile- and 18F-fluorodeoxyglucose-negative, 11C-methionine-positive tumor was detected at the right side of the trachea in the neck. The tumor was removed, along with the thyroid, muscle, and trachea that were involved. The pathological diagnosis was parathyroid carcinoma recurrence. The serum calcium level and intact parathyroid hormone decreased temporarily but had increased again 8 months later. Methionine-positive tumors were found at the right side of the trachea and suspected of being a recurrence. Denosumab reduced her serum calcium level, and radiation successfully suppressed the growth of the recurrent tumors. CONCLUSION: We have reported a rare case of parathyroid carcinoma in a child who has survived for over 40 years. Positron emission tomography of 11C-methionine was useful for detecting local recurrence. This patient's long-term survival has been attributed to multimodality treatment including repeated surgery, medication, and radiation.