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Background CNS germ cell tumors (GCTs) predominantly develop in pediatric and young adult patients with variable responses to surgery, radiation, and chemotherapy. This study aimed to examine the complex and largely unknown pathogenesis of CNS GCTs. Methods We used a combined transcriptomic and methylomic approach in 84 cases and conducted an integrative analysis of the normal cells undergoing embryogenesis and testicular GCTs. Results Genome-wide transcriptome analysis in CNS GCTs indicated that germinoma had a transcriptomic profile representative of primitive cells during early embryogenesis with high meiosis/mitosis potentials, while nongerminomatous GCTs (NGGCTs) had differentiated phenotypes oriented toward tissue formation and organogenesis. Co-analysis with the transcriptome of human embryonic cells revealed that germinomas had expression profiles similar to those of primordial germ cells, while the expression profiles of NGGCTs were similar to those of embryonic stem cells. Some germinoma cases were characterized by extensive immune-cell infiltration and high expression of cancer-testis antigens. NGGCTs had significantly higher immune-cell infiltration, characterized by immune-suppression phenotype. CNS and testicular GCTs (TGCTs) had similar mutational profiles; TGCTs showed enhanced copy number alterations. Methylation analysis clustered germinoma/seminoma and nongerminoma/nonseminoma separately. Germinoma and seminoma were co-categorized based on the degree of the tumor microenvironment balance. Conclusions These results suggested that the pathophysiology of GCTs was less dependent on their site of origin and more dependent on the state of differentiation as well as on the tumor microenvironment balance. This study revealed distinct biological properties of GCTs, which will hopefully lead to future treatment development.

Pediatric intra-cranial germ cell tumors (iGCTs) occur at an incidence of 0.6-1.2 cases/million/year in Western countries. The incidence is reported up to 5 times higher in Japan. It is unknown whether this increased incidence is due to genetic predisposition or environment.The incidence of iGCTs in children ages 0-19 years was evaluated from December 1st, 1996-December 1st, 2016 in stable Japanese immigrant populations living abroad and compared to current native Japanese registry data. The incidence of medullobblastoma was used as a control to account for assumptions in the data. Sites were identified based on historical and population data of known large scale emigration from Japan during a period of industrialization from 1868-1912 which resulted in large, stable Japanese immigrant populations abroad. These three representative sites included Lima, Peru, San Paolo, Brazil, and Vancouver, Canada. Data was collected from registry and hospital-based resources within each region.A review of the Brain Tumor Registry of Japan from 1984-2004 revealed an incidence of 2.5 cases/million/year, lower than previously reported, and a lower incidence of medulloblastoma at 1.2 cases/million/year. Data from Vancouver, Canada, Lima, Peru, and San Paolo, Brazil included a total population of 731,174 Japanese persons. The ratio of all medulloblastoma to iGCT cases in Japan was identified as 1:2 while the ratio was 2:1, 6.5:1, and 5:1, respectively, in the other three locations. The data suggests increased incidence in native Japan may not translate to higher incidence in immigrant Japanese populations abroad and a clear genetic component was not found in our data set.A more precise and comprehensive study is needed to determine the cause of this difference in incidence. This study also emphasizes the importance of national and state registries and is a call to collaborate on state and country level epidemiology studies.

Since a diffuse midline glioma (DMG) has no effective therapy, it is an urgent need to develop new therapeutic strategy. We performed immunotherapy using fusions of autologous dendritic cells (DC) with tumor cells in DMG cases in which tumor tissue was collected by surgery aimed at biopsy, and evaluate the effectiveness and examine the pros and cons of surgical intervention against DMG. Among the patients with basal ganglia or brain stem tumors received surgery at our hospital, 5 adult cases of DMG with H3K27M gene mutation were registered. All patients received radiation therapy and temozolomide chemotherapy. 4 cases received bevacizumab chemotherapy when the patients had recurrence or progression of the disease. The tumor-fused DCs (TFDC) were made by DCs induced from autologous peripheral blood mononuclear cells and tumor cells established from surgical specimens. They were injected subcutaneously into the neck 3 ~ 6 times in a 14 ~ 28 day cycle as the immunotherapy. The adverse events, PFS, and OS were evaluated. A transient complication of facial numbness was observed in one case on right after surgery. Although two patients had CR in those therapies, both of them died of disease (OS at 18 and 32 months, respectively). Since the remaining three cases were registered very recently, adverse event or treatment efficacy judgment have not been determined at the time of submission of the abstract. Serious surgical complications have not been observed in the presented cases. Surgery may be acceptable for DMG as long as the surgery is performed by sufficiently experienced surgeon in an appropriate environment. The TFDC immunotherapy, which can be performed only by collecting a small amount of tumor tissue, expects to be a novel treatment for MDG. In this presentation, the pros and cons of surgical intervention aimed at TFDC immunotherapy for DMG will be examined.

Primary CNS germ cell tumors (GCTs) are rare neoplasms predominantly observed in the pediatric and young adult populations. In line with the hypothesis that the primordial germ cell is the cell-of-origin, histopathological examinations for this pathology involve a diverse range of components mirroring the embryogenic developmental dimensions. Chemotherapy and radiotherapy are the mainstays of treatment, with surgery having a limited role for diagnosis and debulking of residual tissue after treatment. While better management has been achieved over recent decades by modifying radiation coverage and selecting appropriate chemotherapy, standardization of treatment remains challenging, partly due to the low volume of cases encountered in each institution. As the incidence is higher in East Asia, including Japan, the Japan Society for Neuro-Oncology established a multidisciplinary task force to create an evidence-based guideline for CNS GCTs. This guideline provides recommendations for multiple dimensions of clinical management for CNS GCTs, with particular focus on diagnostic measures including serum markers, treatment algorithms including surgery, radiotherapy, and chemotherapy, and under-investigated but important areas such as treatment for recurrent cases, long-term follow-up protocols, and long-term sequelae. This guideline serves the purpose of helping healthcare professionals keep up to date with current knowledge and standards of management for patients with this rare disease in daily clinical practice, as well as driving future translational and clinical research by recognizing unmet needs concerning this tumor.

Background Germinoma preferentially occurs in pediatric and young adult age groups. Although they are responsive to treatment with chemotherapy and radiation, the treatment may cause long-term sequelae in their later lives. Here, we searched for clinical and histopathological features to predict the prognosis of germinoma and affect treatment response. Methods A total of 114 germinoma cases were included in the analysis. We investigated the association between clinical factors, tumor cell content, and progression-free survival (PFS). Results The tumor cell content was widely distributed from Conclusions We found that tumor cell content significantly affected the prognosis of germinomas. Although validation of these results using an independent and larger cohort is necessary, this potentially opens the possibility of leveraging this pathological factor in future clinical trials when stratifying the treatment intensity.

Aims Alterations in microenvironments are a hallmark of cancer, and these alterations in germinomas are of particular significance. Germinoma, the most common subtype of central nervous system germ cell tumours, often exhibits massive immune cell infiltration intermingled with tumour cells. The role of these immune cells in germinoma, however, remains unknown. Methods We investigated the cellular constituents of immune microenvironments and their clinical impacts on prognosis in 100 germinoma cases. Results Patients with germinomas lower in tumour cell content (i.e. higher immune cell infiltration) had a significantly longer progression-free survival time than those with higher tumour cell contents (P = 0.03). Transcriptome analyses and RNA in-situ hybridization indicated that infiltrating immune cells comprised a wide variety of cell types, including lymphocytes and myelocyte-lineage cells. High expression of CD4 was significantly associated with good prognosis, whereas elevated nitric oxide synthase 2 was associated with poor prognosis. PD1 (PDCD1) was expressed by immune cells present in most germinomas (93.8%), and PD-L1 (CD274) expression was found in tumour cells in the majority of germinomas examined (73.5%). Conclusions The collective data strongly suggest that infiltrating immune cells play an important role in predicting treatment response. Further investigation should lead to additional categorization of germinoma to safely reduce treatment intensity depending on tumour/immune cell balance and to develop possible future immunotherapies.

Background: Germ cell tumors (GCTs) preferentially occurs in pediatric and young adult age groups. Chemo- and radiation therapies cause long-term sequelae in their later lives. We searched for clinical and histopathological features to predict the prognosis and affect treatment response, with a future goal of treatment stratification.Methods: A total of 154 GCT cases were included in the analysis. Total of 114 germinoma cases underwent measurement of tumor cell content on H-E specimen, and 82 GCT cases underwent 450K methylation analysis. 12p gain was determined on methylation-based copy number computation and FISH. Association with progression-free and overall survival (PFS/OS) was investigated. Results: The tumor cell content was widely distributed from =50%) showed shorter PFS than those with a lower tumor cell content (

Germ cell tumors (GCTs) are unique neoplasms in that they arise from the migrated cells which were supposed to be directed to gonads. They occur in the central nervous system (CNS), as well as gonadal organs such as testis and ovary. Our genomic analysis revealed that they are characterized by mutations in MAPK and PI3K pathways, chromosomal instability and global hypomethylation in germinoma. However, there were plenty of cases which lacked driver alterations and their pathogenesis is yet to be fully unraveled. Here we aimed to uncover CNSGCT’s pathogenesis from a transcriptomic perspective. Genome-wide transcriptional analysis was performed for 58 CNS and 3 testicular GCTs. This demonstrated that germinoma had a transcriptional profile characteristic to primordial germ cells (PGCs) at early embryogenesis, whereas non-germinomatous germ cell tumors (NGGCTs) showed that with differentiation into various tissues. Integration of transcriptome and methylome corroborated the above finding that pluripotency/meiosis-genes were unmethylated and highly expressed in germinoma compared with NGGCT. Co-analysis with transcriptome of various developmental stages of embryonic cells revealed germinoma and NGGCT had similarities in expression to PGC and embryonic stem cells, respectively. Multi-omics analysis with testicular GCTs (n=134) from TCGA showed shared genomic backgrounds between germinoma-seminoma and NGGCT-nonseminomatous GCT (NSGCT) in mutation and methylation profiles, and contrast in the chromosomal instability, which was more highlighted in testicular GCTs. These new insights into molecular profiles of GCTs lead to a better understanding of the complex pathogenesis of GCTs, and will hopefully provide a clue to future development of new treatments.

Background We integrated clinical, histopathological, and molecular data of central nervous system germ cell tumors to provide insights into their management. Methods Data from the Intracranial Germ Cell Tumor Genome Analysis (iGCT) Consortium were reviewed. A total of 190 cases were classified as primary germ cell tumors (GCTs) based on central pathological reviews. Results All but one of the cases that were bifocal (neurohypophysis and pineal glands) and cases with multiple lesions including neurohypophysis or pineal gland were germinomas (34 of 35). Age was significantly higher in patients with germinoma than other histologies. Comparison between tumor marker and histopathological diagnoses showed that 18.2% of histopathologically diagnosed germinomas were marker positive and 6.1% of non-germinomatous GCTs were marker negative, suggesting a limitation in the utility of markers or histopathology alone using small specimens for diagnosis. Comparison between local and central histopathological diagnoses revealed a discordance of 12.7%. Discordance was significantly less frequent in biopsy cases, implying difficulty in detecting all histopathological components of heterogeneous GCTs. Germinomas at the typical sites (neurohypophysis or pineal gland) showed a better progression-free survival than those at atypical sites (P = 0.03). A molecular clinical association study revealed frequent mitogen-activated protein kinase (MAPK) pathway mutations in males (51.4% vs 14.3%, P = 0.007), and phosphatidylinositol-3 kinase/mammalian target of rapamycin (PI3K/mTOR) pathway mutations in basal ganglia cases (P = 0.004). Basal ganglia cases also had frequent chromosomal losses. Some chromosomal aberrations (2q, 8q gain, 5q, 9p/q, 13q, 15q loss) showed potential prognostic significance. Conclusions The in-depth findings of this study regarding clinical and molecular heterogeneity will increase our understanding of the pathogenesis of this enigmatic tumor.

Intracranial germ cell tumors (iGCTs) are the second most common brain tumors among children under 14 in Japan. The World Health Organization classification recognizes several subtypes of iGCTs, which are conventionally subclassified into pure germinoma or non-germinomatous GCTs. Recent exhaustive genomic studies showed that mutations of the genes involved in the MAPK and/or PI3K pathways are common in iGCTs; however, the mechanisms of how different subtypes develop, often as a mixed-GCT, are unknown. To elucidate the pathogenesis of iGCTs, we investigated 61 GCTs of various subtypes by genome-wide DNA methylation profiling. We showed that pure germinomas are characterized by global low DNA methylation, a unique epigenetic feature making them distinct from all other iGCTs subtypes. The patterns of methylation strongly resemble that of primordial germ cells (PGC) at the migration phase, possibly indicating the cell of origin for these tumors. Unlike PGC, however, hypomethylation extends to long interspersed nuclear element retrotransposons. Histologically and epigenetically distinct microdissected components of mixed-GCTs shared identical somatic mutations in the MAPK or PI3K pathways, indicating that they developed from a common ancestral cell.

OBJECTIVE Human chorionic gonadotropin (HCG) can be detected in a certain population of patients with a germinoma, but the frequency of germinoma HCG secretion and the prognostic value of HCG in the CSF are unknown. METHODS The authors measured HCG levels in sera and CSF in patients with a histologically confirmed germinoma by using a highly sensitive assay known as an immune complex transfer enzyme immunoassay (EIA), which is more than 100 times as sensitive as the conventional method, and they analyzed the correlation between HCG levels and the prognoses of patients with a germinoma. RESULTS HCG levels in sera and CSF of 35 patients with a germinoma were examined with the immune complex transfer EIA. The median CSF HCG levels in patients with a germinoma during the pretreatment and posttreatment evaluations were 192.5 pg/ml (range 1.2–13,116.5 pg/ml) and 18.7 pg/ml (1.2–283.9 pg/ml), respectively. Before treatment, the CSF HCG level was greater than the cutoff value in 85.7% of the patients with a germinoma. The authors compared survival rates among the patients by using a CSF HCG cutoff level of 1000 pg/ml, and the difference was statistically significant between the groups (p = 0.029, log-rank test). CONCLUSIONS Results of this study demonstrate that most germinomas secrete HCG. Patients with a germinoma that secretes higher amounts of HCG in their CSF experienced recurrence more frequently than those with lower CSF HCG levels.

This trial was designed to evaluate the safety and clinical responses to a combination of temozolomide (TMZ) chemotherapy and immunotherapy with fusions of DCs and glioma cells in patients with glioblastoma (GBM). GBM patients were assigned to two groups: a group of recurrent GBMs after failing TMZ-chemotherapy against the initially diagnosed glioma (Group-R) or a group of newly diagnosed GBMs (Group-N). Autologous cultured glioma cells obtained from surgical specimens were fused with autologous DCs using polyethylene glycol. The fusion cells (FC) were inoculated intradermally in the cervical region. Toxicity, progression-free survival (PFS), and overall survival (OS) of this trial were evaluated. Expressions of WT-1, gp-100, and MAGE-A3, recognized as chemoresistance-associated peptides (CAP), were confirmed by immunohistochemistry of paraffin-embedded tumor samples. Patient’s PBMCs of pre- and post-vaccination were evaluated by tetramer and ELISPOT assays. FC-immunotherapy was well tolerated in all patients. Medians of PFS and OS of Group-R (n = 10) were 10.3 and 18.0 months, and those of Group-N (n = 22) were 18.3 and 30.5 months, respectively. Up-regulation and/or cytoplasmic accumulation of CAPs was observed in the recurrent tumors of Group-R patients compared with their initially excised tumors. Specific immune responses against CAPs were observed in the tetramer and ELISPOT assays. The combination of TMZ-treatment leading to up-regulation and/or cytoplasmic accumulation of CAPs, with FC-immunotherapy as a means of producing specific immunity against CAPs, may safely induce anti-tumor effects in patients with GBM.

Herein is described the cases of three children with central nervous system (CNS) tumor, who had switch in handedness occurring before diagnostic confirmation. Although the onset, age, tumor location, and histology were heterogeneous, the diagnosis of CNS tumor was delayed in all three patients. The present experience indicates that switch in handedness should be recognized as a sign of CNS tumor in pediatric patients, and which might prevent delay in diagnosis. Pediatricians should carefully examine such patients who present with some suggestive symptoms of CNS tumor, even when they are unusual, in order to make a timely and appropriate diagnosis.

Pediatric intra-cranial germ cell tumors (iGCTs) occur at an incidence of 0.6–1.2 cases/million/year in Western countries. The incidence is reported up to 5 times higher in the Japan. It is unknown whether this increased incidence is due to tumor biology or environment. The incidence of iGCTs in children ages 0–19 years was evaluated from 12/1/96-12/1/2016 in stable Japanese immigrant populations living abroad compared to current native Japanese registry data. Medulloblastoma incidence was used as a control to account for assumptions in the data. A review of the Brain Tumor Registry of Japan from 1984–2004 revealed an incidence of 2.5 cases/million/year and a lower incidence of medulloblastoma at 1.1 cases/million/year. Sites outside of Japan included Vancouver, Canada, Lima, Peru, and San Paolo, Brazil and together included a population of 853,174 Japanese persons. Within this population, 0 cases of iGCT were identified over a 20-years. The ratio of medulloblastoma to iGCT cases in Japan was identified as 1:2 while the ratio was 2:1, 6.5:1, and 5:1, respectively, in the other three locations. The data suggests increased incidence in the native Japan may not translate to higher incidence in immigrant Japanese populations abroad and a clear genetic component was not found in this preliminary data set. A more precise and comprehensive study is needed to determine the cause of this difference in incidence. This study also emphasizes the importance of national and state registries and is a call to collaborate on state and country level epidemiology studies.

BACKGROUND/OBJECTIVES Relapsed or refractory brain tumors in childhood continue to have a dismal prognosis in spite of intensive multidisciplinary treatment. Cancer immunotherapy is newly developed to be expected as next promising treatment for highly aggressive pediatric cancer. This trial was designed to evaluate the safety and effectiveness of an immunotherapy with fusions of dendritic cells (DCs) and tumor cells in patients with malignant brain tumors. METHODS Patients with histopathologically confirmed malignant and recurrent/refractory brain tumor were eligible for this immunotherapy trial. Autologous cultured tumor cells obtained from surgical specimens were fused with autologous DCs using polyethylene glycol. The fusion cells (FC) were inoculated intradermally in the cervical region and repeated 3–10 times in each 28–84 days cycle. Treatment-related toxicity, progression-free survival (PFS), and overall survival (OS) were evaluated. RESULTS Six patients were enrolled, three with high grade glioma and three with ependymoma. Median age at first course of immunotherapy was 10 years (range 8–25 years) and median follow-up time from the first course of immunotherapy was 13.5 months (range 3–33 months). All patients with immunotherapy were well tolerated to this treatment with no adverse events except local erythema in injected site. Median progression free survival and overall survival were 18 months and 18.5 months, respectively. CONCLUSIONS FC immunotherapy with autologous DCs and tumor cells for brain tumor in children and young adults were extremely well tolerated and showed encouraging responses in this series. Further phase II study of FC immunotherapy is planned to improve survival and reduce treatment related morbidity.

Medulloblastoma is a type of malignant embryonal tumor in childhood that is considered to require multiagent chemotherapy followed by radical resection and craniospinal irradiation (CSI). However, the outcomes of chemotherapy for this tumor in Japan are unclear. Here, we performed a multicenter retrospective study to determine the prognosis of pediatric medulloblastoma patients in Japan treated with the St. Jude medulloblastoma-96 (SJMB96) regimen. Thirty patients with newly diagnosed medulloblastoma received treatment with the SJMB96 regimen at Juntendo University Hospital in Tokyo (n=10), Saitama Medical University International Medical Center in Saitama (n=10), and Tohoku University Hospital in Miyagi (n=10) from 2011 to 2018. All patients underwent tumor resection and CSI, with radiation doses of 23.4Gy for standard-risk patients (n=11) and 39.6Gy for high-risk patients (n=19). Six weeks after radiation therapy, patients received four cycles of high-dose chemotherapy with autologous peripheral blood stem cell transplantation according to the SJMB96 regimen. We found that 5-year overall survival was 80.8% among standard-risk patients and 74.2% among high-risk patients. No treatment-related deaths occurred. Eight patients who experienced recurrence died within 80 months of diagnosis. As these treatment outcomes are comparable to those previously reported outside of Japan, our findings indicate that this regimen is a therapeutic option for medulloblastoma patients in Japan.

Background/Objectives: Relapse or refractory brain tumor in childhood continue to have a dismal prognosis in spite of developing multidisciplinary treatment. Cancer immunotherapy is newly expected as next promising treatment for highly aggressive pediatric cancer. This trial was designed to evaluate the safety and clinical responses to an immunotherapy with fusions of dendritic cells (DCs) and tumor cells in patients with malignant brain tumors. Design/Methods: Patients with histopathologically confirmed high-grade or recurrent brain tumor were eligible for our immunotherapy. Autologous cultured tumor cells obtained from surgical specimens were fused with autologous DCs using polyethylene glycol. The fusion cells (FC) were inoculated intradermally in the cervical region and repeated 3–10 times in each 28–84 days cycle. Toxicity, progression-free survival (PFS), and overall survival (OS) of this trial were evaluated. Results: Six patients were enrolled, three with high grade glioma and three with ependymoma. Median age at first course of immunotherapy was 10 years (range 8–25 years) and median time of follow-up from first course of immunotherapy was 13.5 months (range 3–33 months). All patients with immunotherapy were well tolerated and no adverse event without local erythema in injected site. Median progression free survival and overall survival were 18 months and 18.5 months, respectively. Conclusions: FC immunotherapy with autologous DCs and tumor cells for brain tumor in children and young adults were extremely well tolerated and encouraging. Further phase II study of FC immunotherapy is planned to improve prognosis and overcome treatment related neurological sequelae for highly malignant tumors.

BACKGROUND: DSP-7888 is an experimental cancer vaccine containing peptides that induce WT1-specific CTLs and helper T cells. A phase 1/2 study in pediatric patients (pts) with malignant glioma was conducted to evaluate the efficacy and safety. METHODS: Diffuse intrinsic pontine glioma (DIPG), glioblastoma (GBM) and other high grade glioma (HGG) pts for whom standard therapy failed or who have no available standard therapies were eligible. Pts received five-times DSP-7888 3.5 mg/body via intradermal injection weekly followed by biweekly administration. Response was assessed with MRIs via modified RANO criteria. Recommended dose was determined based on the traditional 3 + 3 design. RESULTS: Four pts were enrolled in phase 1 dose finding part (3.5 mg/body). One patient was replaced due to primary disease progression and the three pts completed DLT evaluation and no DLTs were observed. Therefore, recommended dose was determined as 3.5 mg/body. In a whole study, 18 pts (11 DIPG, 5 GBM and 2 HGG) were enrolled. There was no dose-limiting or unexpected toxicity. Most common treatment related adverse events was controllable injection site reaction only. Disease control (CR+PR+SD) was observed in 7 of 18 pts, with 1 PR and 6 SD. Median OS from initial dose in DIPG exceeded 5 months. Three out of 5 GBM pts are on survival more than 11 months. WT1 specific CTLs induction were observed in several pts. CONCLUSIONS: DSP-7888 is well tolerated at 3.5 mg/body for pts with pediatric malignant glioma. Survival results in DIPG pts exceeded in comparison with historical controls. Moreover, some GBM pts shows encouraging sign of long survival.

OBJECTIVE: Intracranial germ cell tumors (GCTs) are a heterogeneous group of lesions. It is important to obtain the accurate histological diagnosis since the treatment outcomes can depend on histology. Neuroendoscopic biopsy is a minimally invasive procedure and employed widely. But it is not yet clear whether neuroendoscopy can make so accurate diagnosis as craniotomy without increasing the risk of dissemination. We compared the diagnostic rate and recurrence rate of these two procedures. METHODS: Forty patients with intracranial GCTs treated in our institute from 2007 to 2017 were included in this study. More than 6 pieces of tumor tissues were obtained with neuroendoscopy. As highly elevated tumor marker signifies highly malignant tumor, we started treatment without a histological diagnosis. RESULTS: For all patients except those with extremely highly elevated tumor markers, the histological diagnoses were made by neuroendoscopy or craniotomy. Of number cases with germinoma, 3 cases (neuroendoscopy 2, craniotomy 1) relapsed. All three cases were treated with additional chemotherapy and/or radiotherapy to survive. Of number cases with intermediate risk group tumors, 1 case who underwent craniotomy developed recurrence. High-risk tumors were diagnosed by tumor markers in 2 patients, 5 by endoscopy and one by craniotomy. One patient thought to be intermediate risk group by tumor marker, obtained the histological diagnosis of yolk sac tumor. The recurrence rate for neuroendoscopy and craniotomy was 8% and 15% respectively. CONCLUSIONS: Neuroendoscopy is useful for histological diagnosis as well as craniotomy and would not increase recurrence rate.

BACKGROUND Pilocytic astrocytoma is one of the common tumors found during childhood. However, the clinical course of disseminated pilocytic astrocytoma is not clearly known. Here, we present two cases with disseminated pilocytic astrocytoma and discuss the treatment strategy. Patients We treated a 7-year-old female (case 1) and 9-year-old male (case 2) with hypothalamic pilocytic astrocytomas. The results of magnetic resonance imaging showed diffuse spinal dissemination at diagnosis. Chemotherapy with vincristine and carboplatin was administered as the firstline therapy. The tumors showed some shrinkage, and symptoms improved. During chemotherapy, the patients developed allergies to carboplatin. Therefore, we changed the chemotherapy treatment to vincristine. Other adverse events were not observed. In Case 1, we observed an intratumoral hemorrhage and hydrocephalus due to occlusion of the foramen Monro. Endoscopic surgery was performed, and no clinical deficit was observed. Case 2 underwent ventricular peritoneal shunt procedure for communicating hydrocephalus and a reoperation for shunt malfunction because of dense cerebrospinal fluid with elevated protein levels. The patients have not undergone radiotherapy until now. They had no severe clinical symptoms and went to school for 5 and 10 years, respectively, after the diagnoses. CONCLUSION Chemotherapy for disseminated pilocytic astrocytoma is effective and may help in avoiding radiotherapy. Chemotherapy should be administered before radiotherapy, considering long-term complications.

Although 11C-methionine (MET)-PET has been used to diagnose intracranial germ cell tumors (GCTs) arising in the basal ganglia, whether this imaging technique is useful in assessing treatment response and residual tumor is still unclear. The authors report 3 cases of basal ganglia GCTs in which the residual MET uptake at the end of treatment did not develop into a relapse, even without additional treatment. Case 1 is a 22-year-old man who had a second relapse of a left basal ganglia germinoma with diffuse dissemination on the walls of both of his lateral ventricles. MET-PET revealed high MET accumulation around tumors and their surroundings (maximum standardized uptake value [SUVmax] 3.3). After all treatments, MET-PET demonstrated mild tracer accumulation in both basal ganglia (SUVmax 2.2). Progression-free survival was 56 months from the second relapse without any further treatment. Case 2 is a 17-year-old boy with a left basal ganglia germinoma that showed increased MET uptake (SUVmax 4.2). After treatment, MET-PET revealed residual MET uptake (SUVmax 2.4) along the left posterior limb of the internal capsule. Progression-free survival was 52 months from the start of treatment. Case 3 is a 7-year-old boy with a left basal ganglia choriocarcinoma with increased tumor MET uptake (SUVmax 2.5). A minor enhanced mass remained on MRI after treatment with residual MET accumulation (SUVmax 1.4). Progression-free survival was 44 months. Treatment strategies based on MET uptake on PET should be carefully designed in patients with basal ganglia GCTs to avoid overtreatment and complications.

Human chorionic gonadotropin (hCG) production has been utilized as a diagnostic marker for germinoma with syncytiotrophoblastic giant cells (STGC) and choriocarcinoma. Elevated hCG in germinoma is considered to predict less favorable prognosis, and an intensive treatment strategy may accordingly be applied. However, there is some evidence that any germinoma may produce hCG to varying extent. We investigated mRNA expression of the hCG β subunit (hCGβ) using real time quantitative polymerase chain reaction in 94 germ cell tumors (GCTs). Most (93.3 %) GCTs showed higher expression levels compared with that of normal brain tissue (1.09 × 10(0)-1.40 × 10(5) fold). The expression was the highest in GCTs which harbor choriocarcinoma or STGC components. The expression level of hCGβ in germinoma was highly variable (1.09 × 10(0)-5.88 × 10(4) fold) in linear but not bimodal distribution. hCG concentrations in serum and CSF correlated with gene expression, especially when GCTs with single histological component were analyzed separately. The expression was not significantly associated with recurrence in pure germinoma. These results suggest that the serum/CSF hCG levels may need to be interpreted with caution as most GCTs appear to have the capacity of producing hCG irrespective of their histology. The clinical significance of ubiquitous hCG expression in GCTs needs further investigation.

We report the case of a 19-year-old woman with a highly malignant intracranial germ cell tumor (GCT) that developed 14 years after treatment for neurohypophyseal germinoma. Magnetic resonance imaging (MRI) showed a large neurohypophyseal mass and a synchronous lesion in the pineal region. Plasma α-fetoprotein was elevated to 3038 ng/mL. Although the tumor shrank and tumor marker levels normalized after chemotherapy and craniospinal irradiation, treatment was switched to oral etoposide for the residual tumor because of adverse events. MRI after oral etoposide introduction showed additional tumor shrinkage for 27 months after the onset of the second tumor. To the best of our knowledge, this is the longest interval between germinoma onset and the development of highly malignant recurrent GCT to be reported in the English-language literature. Oral etoposide prevented regrowth of the GCT, which has a poor prognosis, and decreased the size of the residual tumor.

Background: The aim of this study was to clarify the degree of information provision to children with brain tumors, factors influencing this provision, and the relationship between this provision and psychosocial consequences. Methods: A total of 157 parents completed a questionnaire on the degree of information provision to their children and sociodemographic and medical characteristics. Parents and their children completed subscales of the Pediatric Quality of Life Inventory (PedsQL) Cancer Module. Relevant factors were investigated using ordinal logistic regression analysis and compared with PedsQL scores by degree of information provision with adjustment for age. Results: The majority of children aged 2 - 4 years received a low level of information only in regard to medical procedure and preparation. The majority of children aged 5 - 11 years were provided information regarding disease symptoms and treatment, but not actual diagnosis. Approximately half of children aged 12 - 18 years were provided detailed information including their actual diagnosis. Older children generally received more information regarding their disease (odds ratio [OR] = 1.3 per 1 year old, P < 0.001), while children with intellectual disability received less (OR = 0.2, P = 0.006). The provision of information did not worsen scores for Procedural Anxiety, Treatment Anxiety, Worry, or Communication. Conclusions: To our knowledge, this is the first report on the degree of information provision to children with brain tumors. Parents of children with brain tumors in Japan provide information dependent on age and intellectual level. The disclosure of information to children regarding their disease might affect their trust of medical and health care professionals.

Some childhood cancer survivors experience employment difficulties. This study aimed to describe pediatric brain-tumor survivors’ employment status. A cross-sectional, observational study was conducted, with questionnaires distributed to 101 pediatric brain-tumor survivors (aged 15 years or older) and their attending physicians from nine institutions in Japan. We compared category and time-series histories for participants’ first-time employment using national census information. Factors related to delayed employment or early employment termination were examined using survival-time analyses. Excluding students and homemakers, 38 brain-tumor survivors (median age 27 years, with 15 years since diagnosis) were of working age. Of these, 12 (32%) were unemployed and 9 (24%) had never been employed. First-time employment occurred later for brain-tumor survivors than the general population, particularly in those with lower educational levels. The number of brain-tumor survivors whose first job was terminated within the first year was higher than that for the general population, particularly in male survivors and germ cell-tumor survivors. Brain-tumor survivors described their working patterns (irregular), job types (specialist or professional), reasons for early termination (unsuitable job), and thoughts about working (they wished to serve their communities but lacked confidence). Brain-tumor survivors are associated with high unemployment rates and multiple unemployment-related factors. Education and welfare systems should identify individual methods of social participation for this group.

Central nervous system germ cell tumours are mysterious tumours, which are common in young male adults in eastern Asia, and include germinoma, mature and immature teratoma, teratoma with malignant transformation, yolk sac tumour, embryonal carcinoma, choriocarcinoma, and mixed tumours of these components. The aetiological mechanism why they mostly develop in the pineal and neurohypophyseal region is still unknown. Their treatment is also a challenge; surgery is demanding, and sometimes biopsy would be preferred. Radiotherapy is effective, but its dose and field would be better reduced for young adults and children. Chemotherapy is effective but not enough for especially non-germinomatous tumours. This chapter presents a comprehensive discussion about those challenging diseases.

Background The initial presentation of central nervous system (CNS) tumors in children frequently mimics other more common and less serious conditions, resulting in diagnostic difficulty and a prolonged time to diagnosis. Yet whether early diagnosis contributes to better life prognosis and functional outcome has not been elucidated. Only a few such reports have originated from Japan, where neuroimaging techniques are the best in the world. We examined the time to diagnosis, the so-called prediagnostic symptomatic interval (PSI), and its impact on prognosis and functional outcome in children with CNS tumors. Methods We reviewed the records of 127 patients aged

There is little information on pediatric oligodendroglial tumor located in the brainstem because of its rarity. Here, we present two pediatric cases of pontine oligodendroglial tumors with radiological findings atypical for diffuse intrinsic pontine glioma. The first patient was an 8-year-old boy. Brain magnetic resonance imaging (MRI) demonstrated diffuse high-intensity changes in the pons, left middle cerebellar peduncle, and part of the left cerebellar hemisphere on T2-weighted and fluid-attenuated inversion recovery images, with an enhanced spot lesion in the left cerebellar hemisphere. The pathological diagnosis was anaplastic oligodendroglioma, and we identified a mutation in histone H3.3 in the tumor specimen. He succumbed to massive disseminated relapse 7 months from diagnosis despite local radiation therapy. The second patient, a 2-year-old girl, was diagnosed with oligoastrocytoma. Brain MRI revealed a large mass in her rostral pons extended to the fourth ventricle with obstructive hydrocephalus. The tumor recurred with intracranial dissemination 56 months post-surgery. Pediatric brainstem oligodendroglial tumors can include histone H3.3-mutated tumors and have a tendency to disseminate throughout the neuroaxis at the time of relapse.

Nitric oxide is a gaseous molecule associated with many distinct physiological functions, and is derived from l -arginine catalyzed by nitric oxide synthase (NOS). Nitric oxide synthase has 3 isoforms: nNOS, iNOS and eNOS. Although these NOS isoforms are believed to play an important role in gingival tissue, little information is available on their morphological dynamics. The aim of this study was to investigate the profiles of NOS isoforms in deficiency of nNOS in gingiva of mice. Twelve male (6 normal (C57BL/6) and 6 nNOS knockout) mice were used. All mice were 5-week-old, weighing approximately 20–25 g each. After sacrifice, the jaws of the mice were removed by mechanical means and specimens analyzed by histology, in situ hybridization and immunohistochemistry. Immunohistochemical observation revealed positive staining for iNOS and eNOS, especially in lamina propria. Similar results in the mRNA expression levels were shown by in situ hybridization analysis. It may suggest that iNOS and eNOS compensated nNOS deficiency in the gingiva of nNOS knockout mice.

BACKGROUND Brainstem tumours account for 10–15% of brain tumors in childhood. Diffuse intrinsic pontine glioma (DIPG) accounts for 60–80% of them and are diagnosed based on clinical findings and radiologic features. All the rest of tumours excluding DIPG are very rare, heterogeneous group of tumours including low-grade glioma and malignant embryonal tumors. It is often difficult to diagnose and decide treatment strategy for their rarity. METHODS To present our experience with atypical brainstem tumours, a retrospective chart review was conducted to identify eligible cases treated over a ten-year period. All tumors involving brainstem, felt not to be DIPGs for absence of clinical/neuroimaging features were included. Demographic information, pathological findings, neuroimaging characteristics, surgical and nonsurgical management plans, and survival data were collected for analysis. RESULTS Between April 2007 and March 2017, 16 patients (14 initial and 2 recurrent) aged from 3 to 20 years were identified. 14 of them were symptomatic and 4 of them were asymptomatic at reference. Of 10 symptomatic cases, 10 were biopsied and pathological diagnosis was low-grade glioma in 8, glioblastoma in 2 cases. They had treatment depending on the pathological diagnosis. Of 4 asymptomatic cases, one with small focal tumour, with no findings suggesting malignant tumour with 11C-methioninePET or MRS, progressed to show typical clinical and image findings of DIPG in a year. For other three, they remain asymptomatic without progression with no treatment for 25months, 60months, and 65 months respectively. Malignant transformation was observed in one with biopsy-conformed oligoastrocytoma with no K27M-H3 mutations treated with chemotherapy and another with pilocytic astrocytoma treated with chemotherapy and radiotherapy. CONCLUSIONS Though molecular findings such as K27M-H3 mutations can predict clinical outcome in some cases, it still remains difficult to diagnose and find treatment strategy of atypical brainstem tumours. The need and usefulness of nationwide registry study is warranted.

BACKGROUND This trial was designed to evaluate the safety and clinical responses to an immunotherapy with fusions of dendritic and glioma cells in patients with lower grade glioma (LGG; WHO grade II-III glioma). METHOD Autologous cultured glioma cells obtained from surgical specimens were fused with autologous dendritic cells (DC) using polyethylene glycol. The fusion cells (FC) were inoculated intradermally in the cervical region of subjects. Toxicity, progression-free survival (PFS), overall survival (OS), and MRI findings were evaluated. DNA for whole exome and RNA for whole transcriptome extracted from HLA-A*24:02 positive glioma cells were analyzed by next generation sequencer. Variant peptides showing strong binding affinity to HLA-A*24:02 but not the corresponding wild type peptides were selected as candidate of neo-antigens. RESULTS The number of subjects of this trial were 24 (initially diagnosed cases: 20, recurrence cases: 4). WHO grade III cases were 20, and grade II cases were 4. Male were 15, and female were 9. Mean of follow up periods were 53.0 months (the longest follow up period: 1322 months). The number of events on PFS and OS were 8 and 6, respectively. Mean of candidate of neo-antigen peptides in HLA-A*24:02 positive patients (n=8) was 34. Among these candidates, twelve types of common neo-antigen peptide were identified. Neo-antigen peptides specifically expressed in the glioma cells from the effective group were not identified. CONCLUSIONS These results indicate that the efficacy of FC-immunotherapy may not always depend on the number of gene mutations or the expression of the specific neo-antigens. FC-immunotherapy, as a means of producing specific immunity against neo-antigens may safely induce anti-tumor effects in patients with LGG. Analysis of prognostic factor in glioma immunotherapy may be the next area of major interest.

Intracranial germ cell tumors (iGCTs) are the second most common brain tumors among children under 15 in Japan. The pathogenesis of iGCTs is largely unexplored. Although a subset of iGCTs is known to have KIT mutation, its impact on the biology and patients' survival has not been established. In this study, we investigated genes involved in the KIT signaling pathway. 65 iGCTs (30 pure germinomas, 14 teratomas, 18 mixed GCTs, 2 yolk sac tumors, 1 choriocarcinoma) were screened for mutation of KIT, KRAS, NRAS, HRAS, BRAF, PDGFRA, and IDH1 by direct sequencing. KIT expression was examined by immunohistochemistry and quantitative PCR. Chromosomal status was analyzed by array-comparative genomic hybridization (aCGH). Somatic mutations were detected only in KIT and RAS, which were frequently observed in pure germinomas (60.0 %), but rare in non-germinomatous GCTs (NGGCTs) (8.6 %). All KIT/RAS mutations were mutually exclusive. Regardless of the mutation status or mRNA expression, the KIT protein was expressed in all germinomas, while only in 54.3 % of NGGCTs. Amplification of KIT was found in one pure germinoma by aCGH. In pure germinomas, high expression of KIT mRNA was associated with the presence of KIT/RAS alterations and severe chromosomal instability. Our results indicate that alterations of the KIT signaling pathway play an important role in the development of germinomas. Pure germinomas may develop through two distinct pathogeneses: one with KIT/RAS alterations, elevated KIT mRNA expression and severe chromosomal instability, and the other through yet an unidentified mechanism without any of the above abnormalities.

Despite the importance of dentin matrix protein 1 (DMP1) in the formation of mineralized tissue, including dentinogenesis and osteogenesis, its precise role in cementogenesis remains to be clarified fully. The purpose of our study was to demonstrate the ultrastructural immunolocalization of DMP1 in monkey molar tooth cementum. Japanese Macaca fuscata monkeys were fixed by perfusion. The upper molar teeth and accompanying periodontium then were dissected and demineralized with EDTA. Cryosections were obtained, incubated in anti-DMP1 polyclonal antibody, and processed by immunoperoxidase and immunogold labeling. Intense immunoperoxidase staining for DMP1 was observed in acellular extrinsic fiber cementum, particularly in Sharpey's fibers. Cementocyte lacunae with canaliculi showed DMP1 staining in the apical region of the tooth root. Electron immunomicroscopy revealed the close proximity of DMP1 to collagen fibrils in Sharpey's fibers at the mineralization front. Intense immunogold labeling was localized on the walls of the cementocyte lacunae in cellular cementum. These results should contribute to better understanding of the role of DMP1, not only in Sharpey's fiber biomineralization, but also in the maintenance of the cementocyte lacunar space in cementum.

Health-related quality of life (HRQOL) is not only a degree of health but also reflects patient perceptions and expectations of health. For children with brain tumors, better understanding of HRQOL requires the use of complementary reports from parents and interviewer-administered reports for children. Here, we aimed to test whether or not the trait anxiety of children and the psychological distress of their parents influence children's and parents' responses to HRQOL questionnaires, and whether or not the report-administration method for children influences children's responses to HRQOL questionnaires.One hundred and thirty-four children aged 5-18 with brain tumors and one of their parents completed the Pediatric Quality of Life Inventory(™) (PedsQL(™)) Brain Tumor Module questionnaires. In addition, the children also completed the State-Trait Anxiety Inventory for Children (STAIC), and the parents also completed the Kessler-10 (K10) and health and sociodemographic characteristics questionnaires. The child questionnaires were administered either by the child (self-administered) or an interviewer. Rater-dependent perceptions about HRQOL were derived from the subscales scores of the PedsQL(™) Brain Tumor Module using structural equation modeling based on a multitrait-multimethod model. The STAIC trait-anxiety score, K10 score, report-administration method, and other health and sociodemographic factors related to each child's or parent's perceptions were identified through multiple linear regression analyses of the questionnaire responses. We used a path analysis to estimate the change in a PedsQL(™) child-reported score that occurs when interviewer-administration changes the child's perception about HRQOL.Surveys for 89 children were self-administered while those for 45 were interviewer-administered. The perceptions of the children and parents were calculated by fitting data to the model (chi-squared P = 0.087, normed fit index = 0.932, comparative fit index = 0.978, standardized root mean squared residual = 0.053, and root mean square error of approximation = 0.054). The children's perception of HRQOL was affected by their STAIC trait-anxiety score (b = -0.43, 95% CI [-0.60, -0.25]). The parent's perception was affected by their child's treatment status (b = 0.26, 95% CI [0.09, 0.43]), the parent's K10 score (b = -0.21, 95% CI [-0.37, -0.04]), and by education level (b = 0.17, 95% CI [0.00, 0.34]). The change in the child-reported PedsQL(™) score in relation to the method of administration ranged from -1.1 (95% CI: -3.5, 1.3) on the procedural anxiety subscale to -2.5 (95% CI: -7.6, 2.6) on the movement and balance subscale.Child-reporting of HRQOL is little influenced by the method of administration. Children's perception about HRQOL tended to be influenced by their trait anxiety, while parents' perception was influenced by their psychological distress, academic background, and their child's treatment status.

We report a case of pineal parenchymal tumor (PPT) in an 11-year-old girl. Brain magnetic resonance imaging (MRI) revealed a large tumor (48 mm) located in the pineal region with heterogeneous enhancement after gadolinium administration. The patient underwent tumor removal with craniotomy; only partial tumor resection could be performed because of massive intratumoral bleeding. Histopathological examination of the tumor showed lobular proliferation of round cells with moderate atypia. Cellularity varied by area, and focal Homer Wright rosettes were identified. Examination of tumor cells revealed a few mitoses (two mitotic figures per 10 high-powered fields), and immunohistochemical staining revealed positivity for synaptophysin, slight positivity for neurofilament protein (NFP) with antibody clone 2F11, and strong positivity for NFP with clone NF-M+H. The pathological diagnosis was pineal parenchymal tumor of intermediate differentiation grade II according to World Health Organization criteria despite a high (22%) MIB-1 labeling index (LI). The patient had a favorable clinical course after an intensified chemotherapy regimen designed for pineoblastoma and radiotherapy administered to the entire neuraxis, followed by stereotactic radiotherapy. In conclusion, MIB-1 LI could be a useful tool for deciding therapeutic strategies for PPT treatment when there is a discrepancy between clinical findings and pathological grading.

X-linked anhidrotic ectodermal dysplasia (XLHED) is characterized by hypoplasia or absence of hair, teeth and sweat glands. In this study, the authors investigated the ectodysplasin-A1 (EDA1) gene was investigated in a Japanese family in which male member, a child, fulfilled the diagnostic for XLHED. The only affected male fulfils the diagnostic criteria for this disorder. His parents were not consanguineous and both of them were healthy. With informed consent, genomic DNA was isolated from oral buccal epithelial cells from all members of the family. Polymerase chain reaction fragments containing nine exons of the EDA1 gene were amplified. Amplified fragments from both the patient and the parents were directly sequenced. The sequence from the patient revealed a missense mutation (G643A) in exon 5 of the EDA1 gene, which changes codon 215 from glycine to arginine. Heterozygosity was demonstrated in the mother. The present results indicate that amino acid substitution occurs, disrupting the transmembrane domain, and strongly suggest that this was the disease-causing mutation in this family.

Favorable responses to temozolomide chemotherapy have recently been reported in primary central nervous system lymphoma (PCNSL) patients who are refractory to high-dose methotrexate therapy. The gene encoding the DNA repair enzyme O (6)-methylguanine-DNA methyltransferase (MGMT) is transcriptionally silenced by promoter methylation in several human tumors, including gliomas and systemic lymphomas. MGMT promoter methylation is also a prognostic marker in glioblastoma patients treated with temozolomide. To validate temozolomide treatment in PCNSL, we applied methylation-sensitive high resolution melting (MS-HRM) analysis to quantitate MGMT methylation in PCNSL. MGMT promoter methylation was detected in tumors from 23 (51%) of 45 PCNSL patients, 11 of which were considered to have high (more than 70.0%) methylation status. Of the five recurrent PCNSLs treated with temozolomide, four cases responded, with three achieving complete response and one, a partial response. All four responsive PCNSLs had methylated MGMT promoters, whereas the non-responsive recurrent PCNSL did not. Thus, the use of quantitative MS-HRM analysis for the detection of MGMT promoter methylation has been suggested in PCNSL for the first time. The assay allows rapid and high-throughput evaluation of the MGMT methylation status, and seems to be promising in clinical settings. MGMT promoter methylation may become a useful marker for predicting the response of PCNSLs to temozolomide.

Amelogenesis imperfecta (AI) is associated with mutations in a number of genes, including AMELX and ENAM. However, the precise mechanism leading to enamel malformation in different AI types remains to be elucidated. In the present study, we investigated morphological change in tooth germ obtained from ENAM-mutant mice (Enam(Rgsc521) homozygotes) as a model for human AI using histological and immunohistochemical methodologies. The results showed that ameloblasts detached from developing dentin and lost cell polarity in mutant mice at post-natal day 3. Cyst-like structures, including amelogenin-immunopositive materials, were observed between these detached cells and the dentin. No enamel-like structure, however, was observed in the cusp of the crown. These results suggest that enamelin acts as an adhesion molecule and is involved in ameloblast cell differentiation during the early stages of tooth development.

The study investigated the remineralization effect of calcified seaweed with large amounts of calcium (Ca), magnesium (Mg), sodium (Na), fluorine (F) and phosphorus (P). Human third molars were used in the experiment with the approval of the Ethics Committee of Tokyo Dental College. Cementum was removed from the cervical area around the teeth exposing the dentin. Small dentin blocks were prepared and immersed in acetic acid-sodium acetate buffer for 24 hours. Samples were immersed in remineralized liquid or saliva solution with or without calcified seaweed for 2 weeks. Structural changes in remineralization, depth of demineralization and loss in mineral volume were evaluated by contact microradiogram (CMR). Qualitative analysis was carried out with electron probe microanalyzer (EPMA). Morphology of crystal was observed using high-resolution transmission electron microscopy (HR-TEM). CMR image analysis revealed that part of the samples immersed in the solutions underwent remineralization. However, there was no significant difference in the degree of remineralization. EPMA observation of dentin partly detected Ca and P but not Mg or F. HR-TEM analysis revealed changes in crystal structure caused by Mg and F, which influenced remineralization in a small amount.

The incidence of root caries and hyperesthesia in elderly people tend to increase with increasing age. This can be prevented by enhancing the root surfaces against aciduric bacteria. In order to prevent root caries, a chewing gum containing calcified seaweed rich in Ca, Mg, Na, F and P was created. A dentin block was made from the cervical part of the third molar after removing the cementum. The dentin blocks were immersed in remineralizing solution with extract of the gum with or without calcified seaweed for 2 weeks. The dentin blocks were immersed in demineralizing solution for 6 hours and acid resistance was evaluated after. Demineralization was evaluated by CMR image, demineralization depth (Ld) and mineral loss quantity (ΔZ) by image analysis, qualitative analysis by EPMA and the surface structure with the SEM. CMR image analysis revealed that the region immersed in aciduric solution had less quantity of demineralization than the region which was not immersed. A significant difference in Ld and Δ Z of the demineralization area after the aciduric treatment between the solution with calcified seaweed and the solution without aciduric treatment (p

BACKGROUND: Central nervous system germ cell tumors (CNS-GCT) are a heterogeneous group of diseases. The management of CNS-GCT remains controversial. Objective: To clarify the relapse pattern and outcome of patients with recurrent CNS-GCT in order to find problems with current initial management. METHODS: Chart review of patients with recurrent CNS-GCTs treated in two institutions from 2007 to 2017. RESULTS: There were 19 germinomas and six non-germinomatous germ cell tumors (NGGCT), referred to us for the first (n=19), second (n=4), third (n=1) and fourth (n=1) relapse. The time from the diagnosis to the first relapse was within three years for 15 patients (range 6- 24 months) and over three years (range 36 -144 months) for 10 patients. The site of recurrence was outside the irradiation field for 13 germinoma cases, and inside for six germinoma and six NGGCT patients. Thirteen patients with first recurrent germinoma survived with chemotherapy and re-irradiation, and one failed with high-dose chemotherapy only. Two patients with second relapse of germinoma were successfully treated with high-dose chemotherapy only. One patient with second relapse of germinoma refractory to chemotherapy and re-irradiation is alive with oral metronomic etoposide for nine years. Only one of six NGGCT patients survived in spite of intensive treatments. CONCLUSIONS: Germinoma patients treated with reduced radiotherapy and chemotherapy can relapse both within and outside irradiation fields, very early and very late in longer follow-up. These results can teach us not only the optimal management of recurrent disease, but also suggest possible novel management of initial disease.

Objectives: The aim of this study was to describe the ultrastructure of the dentogingival border at replanted teeth and implants. Material and methods: Wistar rats (8 weeks old) were divided into groups for replantation and implantation experiments. In the former, the upper right first molars were extracted and then immediately replanted. In the latter, pure titanium implants were used. All tissues were fixed, demineralized and embedded in epoxy resin for ultrastructural observations. Results: One week after replantation, the junctional epithelium was lost, and the oral sulcular epithelium covered the enamel surface. The amount of the epithelium increased in 2 weeks, and resembled the junctional epithelium, and the internal basal lamina and hemidesmosomes were formed in 4 weeks. One week after implantation, peri-implant epithelium was formed, and in 2 and 4 weeks, this epithelium with aggregated connective tissue cells were observed. In 8 weeks, the peri-implant epithelium receded, and aligned special cells with surrounding elongated fibroblasts and bundles of collagen fibers appeared to seal the implant interface. Conclusion: In replantation of the tooth, the internal basal lamina remained at the surface of the enamel of the replanted tooth, which is likely to be related to regeneration of the junctional epithelium and the attachment apparatus at the epithelium–tooth interface. Following implantation, a layer of cells with characteristics of connective tissue cells, but no junctional epithelium and attachment apparatus, was formed to seal the site of the implant.

Tooth enameloid of medaka as a representative of human tooth enamel was analyzed by high-resolution transmission electron microscope (HR-TEM), electron probe microanalyzer (EPMA) and micro-X-ray diffraction to deepen the knowledge on the crystal formation of tooth enamel. HR-TEM observation showed that enameloid crystals, with incomplete slender hexagonal shape, sometimes became fused with each other when the density of crystals increased. EPMA analysis showed clear image maps of calcium, phosphate and iron. The element analysis indicated high concentration of calcium and phosphate. Micro-X-ray diffraction showed that enameloid crystals are composed of relatively well-crystallized hydroxyapatite. Each (211), (112), (210) and (002) reflection peaks was clearly detected. It is suggested that the medaka is useful for research of developing tooth because it is polyphyodont and has a short lifespan.