[Autoimmune hepatitis developed after COVID-19 vaccination and ameliorated temporarily but relapsed or stopped improving, and finally resolved by steroid therapy:a report of three cases].

The severe acute respiratory syndrome coronavirus 2 vaccine has contributed to infection control and the prevention of complications due to coronavirus disease 2019 (COVID-19). Conversely, the COVID-19 vaccine has been associated with adverse effects due to liver injury caused by autoimmunity or drugs. To date, Japanese journals have only published five reports of autoimmune liver damage associated with the COVID-19 vaccination. Although the pathogenic mechanism has not yet been fully elucidated, corticosteroids or azathioprine have shown effectiveness in certain patients. However, there have been cases of liver injury resulting in deaths. Here, we encountered three patients who developed autoimmune hepatitis (AIH) within 10 days following vaccination. All three patients were treated with prednisolone (PSL) and achieved remission. However, the serum alanine aminotransferase levels in all cases were observed to either increase or cease to improve during the therapeutic course before PSL administration. It is therefore imperative to closely monitor liver injury after the COVID-19 vaccination. In cases where AIH is suspected and a recurrence of liver dysfunction occurs, PSL may be administered. Future considerations should not only encompass the underlying mechanism by which autoimmunity contributes to the development of liver injury following COVID-19 vaccination but also the optimal treatment period for PSL and the long-term prognosis of AIH after COVID-19 vaccination.

Waldenström Macroglobulinemia and Non-IgM-Type Lymphoplasmacytic Lymphoma Are Genetically Similar.

INTRODUCTION: Waldenström macroglobulinemia (WM) represents a subset of lymphoplasmacytic lymphoma (LPL) with the immunoglobulin (Ig)M paraprotein. MYD88 L265P and CXCR4 mutations are common mutations in WM patients, and mutations in ARID1A and KMT2D (MLL2) have also been reported. However, little information has been accumulated on genetic changes in LPL with other paraproteins like IgG. METHODS: We therefore aimed to evaluate genetic differences between WM and LPL with non-IgM paraprotein (non-IgM-type LPL) using targeted next-generation sequencing (NGS) in 20 Japanese patients (10 with WM, 10 with non-IgM-type LPL). RESULTS: Mutations were detected in ARID1A (10%), CXCR4 (20%), MYD88 (90%), and KMT2D (0%) for WM patients and in ARID1A (10%), CXCR4 (20%), MYD88 (70%), and KMT2D (10%) for non-IgM-type LPL patients. No significant differences were identified. No mutations were detected in NOTCH2, PRDM1, CD274 (PD-L1), PDCD1LG2 (PD-L2), RAG2, MYBBP1A, TP53, or CD79B. DISCUSSION: Mutant allele frequency in MYD88 L265P did not differ significantly between WM and non-IgM-type LPL. Most mutations detected by NGS were subclonal following MYD88 L265P, although one non-IgM-type LPL patient harbored only CXCR4 S338X mutation. Our NGS analyses reveal genetic characteristics in LPL patients and suggest genetic similarities between these two subsets of LPL, WM and non-IgM-type.

Prognostic Implication of DNA Methylation Signature in Atypical Choroid Plexus Papilloma With Intracranial Dissemination.

An underestimation of pathologic diagnosis could be expected if disseminated choroid plexus tumors (CPTs) are diagnosed as lower grade tumors. Thus, molecular diagnosis using genome-wide DNA methylation profiling may be useful for clarifying the malignant potential of the tumor entity. Herein, we report a 2.7-year-old girl of pathologically atypical choroid plexus papilloma with intracranial dissemination. She was treated without radiotherapy and has been well, without recurrence for 32 months following the diagnosis. Subsequently, after a year from the diagnosis, T-stochastic neighbor embedding analysis was performed on methylation data of the case and compared with those of reference data of CPTs, revealing that the case was separated from the cluster of "Plexus tumor subclass pediatric B," which includes a majority of choroid plexus carcinomas with the worst prognosis of these entities, and was categorized into the cluster of "Plexus tumor subclass pediatric A" consisting of choroid plexus papilloma and atypical choroid plexus papillomas diagnosed pathologically. Our case indicates the clinical significance of molecular confirmation for diagnosis among CPTs, particularly lower grade tumors with dissemination.

Malignant brain tumor in an infant showing histopathological features of yolk sac tumor but genetic and epigenetic features of AT/RT.

SMARCA4 pathogenic variants are rarely detected in pediatric brain tumors other than atypical teratoid rhabdoid tumors (AT/RTs) without INI1 deficiency or in some cases of medulloblastoma. Here, we report an atypical intracranial immature teratoma that recurred as a yolk sac tumor with metastatic spinal and lung lesions. Sequencing of the tumor revealed two SMARCA4 variants, including a splice-site variant and a non-synonymous variant of uncertain significance. Additionally, the methylation signature of the tumor was close to that of AT/RTs. Our case might be a yet-unrecognized subtype of pediatric tumors in which inactivation of SMARCA4 contributes to the pathogenesis.

Radiologic-pathologic association of tumor-like lesions with inflammation in cerebral white matter: Comparison of two cases with distinct clinical outcomes.

Here, we report two cases showing tumor-like white matter lesions; one case was diagnosed as having inflammatory disease, and the other was diagnosed as having astrocytoma. Their outcomes were completely distinct despite similar pathology. Prior to biopsy, perfusion computed tomography (CT) and magnetic resonance imaging (MRI) were conducted. The two mass-forming lesions were distinct in edema level and vascularity patterns on CT and MRI. However, pathological examination of brain biopsy specimens revealed commonalities, including (1) proliferation of glial cells, (2) perivascular lymphocytic infiltration, and (3) appearance of numerous macrophages. Although atypical astrocytes proliferated in both cases, nuclear atypia was more distinct in case 2 than in case 1. The immunohistochemical results were the same for both cases: isocitrate dehydrogenase 1 (IDH1) R132H mutation was negative, and alpha thalassaemia mental retardation X-linked (ATRX) was retained. Faint immunoreactivity for p53 was observed in a few glial cells, and Ki-67 immunoreactive cells were markedly reduced in numbers (< 1%). Inflammatory reactions were evident in both cases: T cells dominantly infiltrated over B cells in the perivascular area in case 1, whereas both T and B cells infiltrated in case 2. Molecular analysis revealed wild-type IDH1 and IDH2 in both cases. However, a telomerase reverse transcriptase (TERT) sequence mutation was detected in case 2 but not in case 1. Eventually, case 1 was diagnosed as having inflammatory lesions, whereas case 2 was diagnosed as having diffuse astrocytoma associated with inflammatory reactions. The prognosis was favorable for case 1, whereas case 2 died 10 months following biopsy. These data indicated the diagnostic value of molecular analysis, for example, a TERT mutation, in association with the radiological findings. Although in case 2, histopathological evidence did not suggest high-grade glioma, the case met the new diagnostic criteria: "diffuse astrocytic glioma, IDH wild-type, with molecular features of glioblastoma, World Health Organization (WHO) grade IV," according to cIMPACT-NOW, update 3. Thus, interdisciplinary approaches are essential for accurate diagnosis of newly categorized white matter diseases.

Mutation profiling of uterine cervical cancer patients treated with definitive radiotherapy.

OBJECTIVE: To elucidate tumor mutation profiles associated with outcomes of uterine cervical cancer (UCC) patients treated with definitive radiotherapy. METHODS: Ninety-eight patients with newly diagnosed and pathologically confirmed UCC (82 squamous cell carcinomas, 12 adenocarcinomas, and four adenosquamous carcinomas) who were treated with definitive radiotherapy were analyzed. DNA was extracted from pre-treatment tumor biopsy specimens. The exons of 409 cancer-related genes were sequenced using a next-generation sequencer. Genetic mutations were identified and analyzed for correlations with clinical outcome. RESULTS: Recurrent mutations were observed in PIK3CA (35.7%), ARID1A (25.5%), NOTCH1 (19.4%), FGFR3 (16.3%), FBXW7 (19.4%), TP53 (13.3%), EP300 (12.2%), and FGFR4 (10.2%). The prevalence of mutations in FGFR family genes (i.e., FGFR1-4) was almost as high (24.5%) as that in PIK3CA and ARID1A, both of which are well-studied drivers of UCC. Fifty-five percent (21 of 38) of the identified FGFR mutations were located in the FGFR protein tyrosine kinase domain. Five-year progression-free survival (PFS) rates for FGFR mutation-positive patients (n = 24) were significantly worse than those for FGFR mutation-negative patients (n = 74) (43.9% vs. 68.5%, respectively; P = 0.010). Multivariate analysis identified FGFR mutations as significant predictors of worse 5 year PFS (P = 0.005), independent of clinicopathological variables. CONCLUSIONS: FGFR mutations are associated with worse PFS in UCC patients treated with definitive radiotherapy. These results warrant further validation in prospective studies.

Phase II study of reduced-dose craniospinal irradiation and combination chemotherapy for children with newly diagnosed medulloblastoma: A report from the Japanese Pediatric Brain Tumor Consortium.

BACKGROUND: Standard doses of craniospinal irradiation (CSI) are 23.4 Gy for patients with average-risk and 36 Gy for those with high-risk medulloblastoma (MB). We investigated whether intensified chemotherapy including intrathecal chemotherapy with simultaneous irradiation is able to reduce CSI dose to 18 Gy. METHODS: Newly diagnosed average-risk patients aged 3-11 years and high-risk patients aged 3-18 years were eligible. Patients with Stage M1-4 disease were classified as high-risk MB and the others, including M0 patients with >1.5 cm2 postoperative residual tumor, were classified as average-risk MB. Patients received chemotherapy consisting of cyclophosphamide, etoposide, cisplatin, and vincristine. Radiotherapy was started concomitantly with the second course of chemotherapy. Radiation doses were 50 Gy to the primary site and 18 Gy to the craniospinal axis. Average-risk patients received five courses of chemotherapy. High-risk patients received high-dose chemotherapy consisting of thiotepa and melphalan following four courses of chemotherapy. All patients received intrathecal methotrexate. RESULTS: From 2006 to 2014, 48 patients (35 average and 13 high risk) who met the eligibility/exclusion criteria were enrolled. The 3-year progression-free survival (PFS) and 3-year overall survival (OS) were 90.5% (standard error 5.2%) and 93.9% (4.2%), respectively, for average-risk patients, and 100% and 100%, respectively, for high-risk patients. There was no leukoencephalopathy or treatment-related deaths. Two patients experienced secondary cancer. CONCLUSIONS: These results suggest that CSI 18 Gy is adequate at least in a proportion of patients with MB treated with intensified chemotherapy including intrathecal methotrexate and simultaneous irradiation, though the results in high-risk patients were only exploratory.

Oligodendroglioma showing pleomorphic xanthoastrocytoma-like perivascular microlesion: With IDH1, TERT promoter mutation and 1p/19q codeletion detected in both components.

We report a histological and genetic study of concurrent oligodendroglioma and a microscopic pleomorphic xanthoastrocytoma (PXA)-like lesion in a 48-year-old male. He presented with generalized seizure, and magnetic resonance imaging revealed a nonenhanced left frontal lobe mass suggesting low-grade glioma. The patient underwent craniotomy and tumor resection. Histopathological examination of the surgical specimen showed an oligodendroglioma with a PXA-like element; the latter measured 0.9 mm and occupied a Virchow-Robin space of the superficial cortex. The whole tumor had no elevated mitotic activity, microvascular proliferation or necrosis. Each component was immunohistochemically isocitrate dehydrogenase (IDH1)-R132H positive, p53 negative and ATRX positive. Genetic analyses clarified identical IDH1 G395A mutation, promoter C228T mutation and 1p/19q codeletion in both elements. Careful integration of histology and telomerase reverse transcriptase (TERT) molecular parameters revealed that this case was an oligodendroglioma showing PXA-like features, rather than a collision tumor. This case provides further insights into the gliomagenesis.

A rare case of BRAF V600E-mutated epithelioid glioblastoma with a sarcomatous component.

Epithelioid glioblastoma is a rare subtype of glioblastoma, but the coexistence of a sarcomatous component is even rarer. An 80-year-old woman was admitted to our hospital with somnolence. Magnetic resonance imaging revealed a cystic lesion with a solid component in the left temporal-parietal lobe. Histopathological examination of the resected tumor revealed three components; namely, typical glioblastoma, sarcomatous and epithelioid components at a ratio of about 5:3:2. All components were immunohistochemically positive for vimentin and mutated BRAF (V600E) and showed focal expression of glial fibrillary acidic protein and cytokeratin AE1/AE3, but they were negative for isocitrate dehydrogenase 1. Genetic analysis revealed that both the sarcomatous and epithelioid components harbored BRAF T1799A (V600E) mutation and homozygous deletion of cyclin-dependent kinase inhibitor 2A/B. We diagnosed this tumor as epithelial glioblastoma with a sarcomatous component. Our results indicate that even when the epithelial component is not dominant, immunohistochemical and genetic investigation of BRAF mutations is useful for the diagnosis of glioblastoma subtypes. In particular, although the prognosis of epithelial glioblastoma is poor, potentially effective targeted therapies for BRAF V600E-mutated tumors are available.

Recurrent lumbar-origin osteoblastoma treated with multiple surgery and carbon ion radiotherapy: a case report.

BACKGROUND: Although osteoblastoma is an uncommon benign bone tumor, it sometimes behaves in a locally aggressive fashion. We herein report a case of recurrent lumbar spine osteoblastoma that was treated by repeated surgery and carbon ion radiotherapy. CASE PRESENTATION: A 13-year-old Japanese girl presented with left side lumbar pain. Computed tomography and magnetic resonance imaging of the lumbar spine demonstrated a tumorous lesion in the left side pedicle of L4. Although gross total resection of the mass, including the nidus, was performed in the initial surgery, recurrence was observed repeatedly in the short term and the pathological diagnosis of all of the resected tumors was conventional osteoblastoma. We finally performed carbon ion radiotherapy after the patient's 3rd palliative operation, and achieved a good outcome. No further recurrence has been observed in 10 years of follow-up. CONCLUSION: We performed carbon ion radiotherapy for a case of recurrent spinal osteoblastoma and achieved a good outcome without recurrence at 10 years after carbon ion radiotherapy treatment. To the best of our knowledge, this is the first case of osteoblastoma that was treated with carbon ion radiotherapy after multiple surgeries.

Genome-wide DNA methylation profiling shows molecular heterogeneity of anaplastic pleomorphic xanthoastrocytoma.

In the revised World Health Organization classification 2016, anaplastic pleomorphic xanthoastrocytoma (PXA) has been newly defined as a variant of the PXA entity. Furthermore, some anaplastic PXA were reported to have extremely poor prognosis which showed a type of pediatric glioblastoma (GBM) molecular profile. Recent integrated molecular classification for primary central nervous system tumors proposed some differences between histological and molecular features. Herein, in a genome-wide molecular analysis, we show an extreme aggressive anaplastic PXA that resulted in a pediatric GBM molecular profile. A full implementation of the molecular approach is the key to predict prognosis and decide the treatment strategy for anaplastic PXA.

Prognostic impact of trisomy 21 in follicular lymphoma.

The chromosomal abnormalities associated with follicular lymphoma (FL) prognosis are not fully elucidated. Here, we evaluated the pattern of chromosomal abnormalities in FL, and clarified the correlations between the cytogenetic features and clinical outcome. Cytogenetic analysis was performed using standard methods of Giemsa-banding at diagnosis for 201 FL patients admitted to our hospitals between 2001 and 2013. The identified chromosomal abnormalities were: t(14;18)(q32;q21) (59·2%), +X (17·9%), del(6)(q)/-6 (16·9%), +7 (14·4%), abnormality of 1q12-21/1q (12·9%), del(13)(q)/-13 (11·9%), abnormality of 3q27 (10·4%), abnormality of 10q22-24 (10·0%), +12/dup(12)(q) (10·0%), abnormality of 1p21-22/1p (9·0%), +18 (9·0%), del(17)(p)/-17 (5·0%), and a complex karyotype (54·7%). Patients with trisomy 21 had a significantly shorter progression-free survival (P = 0·00171) and overall survival (OS) (P < 0·001) than those without trisomy 21; additionally, patients with trisomy 21 in the rituximab-treated cohort also had a significantly shorter OS (P = 0·000428). Multivariate analysis identified trisomy 21 as an independent risk factor in our cohorts with or without t(14;18) (P = 0·015). In conclusion, the presence of trisomy 21 was an independent risk factor for in FL. Chromosomal analysis of FL patients at diagnosis can provide useful information about their expected survival.

Presacral malignant teratoid neoplasm in association with pathogenic DICER1 variation.

We report two malignant sacrococcygeal tumors in infants that were associated with pathogenic DICER1 variation. These tumors were composed of primitive neuroepithelium, embryonal rhabdomyosarcoma, and cartilage and initially diagnosed as immature teratomas. One child developed intracranial metastasis and died. The second child underwent surgery and chemotherapy and achieved complete remission. This child subsequently developed five additional DICER1-associated neoplasms by age nine. Genetic analysis revealed that both tumors harbored biallelic pathogenic DICER1 variation. We believe these cases represent another novel subtype of DICER1-associated tumor. This new entity, which we propose to call DICER1-associated presacral malignant teratoid neoplasm, may be difficult initially to distinguish from immature teratoma, but recognizing it as an entity can prompt appropriate classification as an aggressive malignancy and facilitate appropriate genetic counseling, DICER1 germline variant testing, screening, and education.

Multiplex ligation-dependent probe amplification analysis is useful for detecting a copy number gain of the FGFR1 tyrosine kinase domain in dysembryoplastic neuroepithelial tumors.

PURPOSE: Dysembryoplastic neuroepithelial tumors (DNTs) are slow-growing glioneuronal tumors, and their genetic backgrounds are getting unveiled. Recently, fibroblast growth factor receptor 1 internal tandem duplication (FGFR1-ITD) of the tyrosine kinase domain (TKD) has been demonstrated by whole-genome sequencing. METHODS AND RESULTS: Here, we analyzed 22 DNTs using multiplex ligation-dependent probe amplification (MLPA) with formalin-fixed paraffin-embedded specimens and found a copy number gain in TKD of FGFR1 (13 cases, 59%), which suggested the presence of FGFR1-ITD. Another 5 DNTs harbored FGFR1 hot spot mutations including a double mutant case, and FGFR1 alterations were detected in 18 DNTs (82%). The BRAF V600E mutation, another important mutation in DNTs, was not observed. CONCLUSIONS: With recent findings of less frequent or absent FGFR1-ITD in pilocytic astrocytomas or rosette-forming glioneuronal tumors, the analysis of FGFR1 aberrations, especially FGFR1-ITD, was suggested to be helpful to discriminate DNTs from their histological mimics.

A novel CYCS mutation in the α-helix of the CYCS C-terminal domain causes non-syndromic thrombocytopenia.

We report a patient with thrombocytopenia from a Japanese family with hemophilia A spanning four generations. Various etiologies of thrombocytopenia, including genetic, immunological, and hematopoietic abnormalities, determine the prognosis for this disease. In this study, we identified a novel heterozygous mutation in a gene encoding cytochrome c, somatic (CYCS, MIM123970) using whole exome sequencing. This variant (c.301_303del:p.Lys101del) is located in the α-helix of the cytochrome c (CYCS) C-terminal domain. In silico structural analysis suggested that this mutation results in protein folding instability. CYCS is one of the key factors regulating the intrinsic apoptotic pathway and the mitochondrial respiratory chain. Using the yeast model system, we clearly demonstrated that this one amino acid deletion (in-frame) resulted in significantly reduced cytochrome c protein expression and functional defects in the mitochondrial respiratory chain, indicating that the loss of function of cytochrome c underlies thrombocytopenia. The clinical features of known CYCS variants have been reported to be confined to mild or asymptomatic thrombocytopenia, as was observed for the patient in our study. This study clearly demonstrates that thrombocytopenia can result from CYCS loss-of-function variants.

Scedosporium apiospermum infectious scleritis following posterior subtenon triamcinolone acetonide injection: a case report and literature review.

BACKGROUND: Ubiquitous fungi of the Scedosporium apiospermum species complex (SASC) cause various opportunistic infections. Posterior subtenon triamcinolone acetonide (STTA) injection is a standard therapy for intraocular inflammation and macular edema. We report a case of Scedosporium apiospermum infectious scleritis after a posterior STTA injection. CASE PRESENTATION: A 75-year-old man received a posterior STTA injection to treat macular edema in his left eye. After 3 months, he complained of ocular pain and hyperemia in his left eye. Examination showed a subtenon abscess in the site corresponding with the STTA injection. After incising the abscess, the smear revealed numerous conidia-like structures. Although we suspected fungal infection and started topical voriconazole (VRCZ) and levofloxacin, the inflammation of the eye worsened. Fungal culture revealed filamentous fungus growth. Subsequently, we added systemic VRCZ and performed surgical debridement of the infected sclera and Tenon's capsule. Pathology of the sclera showed fungal hyphae. The antifungal susceptibility test revealed low minimum inhibitory concentrations for micafungin, VRCZ and miconazole (0.06, 0.25 and 0.5 µg/mL, respectively). After 2 months, the ciliary injection subsided and VRCZ therapy was stopped. However, subtenon abscess recurred 1 month after discontinuation of topical VRCZ. Surgical debridement and topical VRCZ were resumed, with the eye finally improving after 5 months of management. The fungal species was identified as Scedosporium apiospermum sensu stricto morphologically and by DNA sequencing. CONCLUSIONS: This case was successfully treated by topical and systemic VRCZ and repeated surgical debridement. Infectious scleritis caused by SASC rarely develops after posterior STTA. SASC can produce conidia in the enclosed subtenon space. Late-onset infectious scleritis after a posterior STTA injection suggests the presence of a fungal infection, including SASC, thereby requiring extensive and prolonged medical and surgical treatment.

Cerebellar high-grade astrocytoma with IDH mutations in the elderly: A report of two cases.

Cerebellar high-grade gliomas are rare, and likely to affect younger patients compared with those of cerebral origin. Recent genetic analyses have revealed that isocitrate dehydrogenase (IDH) 1/2 mutations are rare in infratentorial gliomas. In this paper, we report two elderly cases of IDH-mutated cerebellar high-grade glioma with unusual histological features and uncommon patient ages. One case was an 83-year-old man, whose tumor was predominantly composed of densely packed round-to-polygonal epithelioid cells. The other was a 75-year-old woman's high-grade astrocytoma characterized by cord-like structures and the perivascular papillary arrangements with varying amounts of myxoid matrix. The former harbored IDH1 R132H mutation, whereas the latter had IDH2 R172K mutation. According to our literature review, eight cases of IDH-mutated infratentorial gliomas including the present cases have been reported, and four had mutations other than IDH1 R132H. Moreover, we herein report the first elderly case of IDH2-mutation. Although the number is limited, IDH-mutant infratentorial diffuse gliomas may have clinical, histological and genetic features different from supratentorial cases.

Anaplastic ganglioglioma with epithelioid cell components.

A 40-year-old man was admitted to our hospital because of disorientation and mild left-sided weakness. Radiological examination revealed a solid and cystic tumor in the right temporal lobe, and total resection was performed. Histologically, the tumor was composed mainly of low-grade gangiloglioma and had some high-grade glial components with focal necrosis and microvascular proliferations. In the high-grade component, there were epithelioid cells with round cytoplasm and eccentric nuclei. The high-grade area with epithelioid cells was intermingled within the low-grade area, which suggests that epithelioid cells were an anaplastic transformation of ganglioglioma. The epithelioid cells were histologically similar to neoplastic cells of epithelioid glioblastoma (E-GBM), a rare aggressive variant of isocitric dehydrogenase wild-type glioblastoma. A BRAF V600E mutation, frequently observed in E-GBM, was detected in both the ganglioglioma and epithelioid cell components. The epithelioid cells were mitotically active, which suggests that if the surgery was delayed, the histological appearance might have eventually evolved into E-GBM. Indeed, a case of pleomorphic xanthoastrocytoma which transformed into E-GBM after a long latency was reported elsewhere. This is the first report to describe focal epithelioid cells in anaplastic ganglioglioma.

Combined morphological, immunohistochemical and genetic analyses of medulloepithelioma in the posterior cranial fossa.

Medulloepithelioma is a rare and highly malignant primitive neuroectodermal tumor that usually occurs in childhood. The diagnosis of this entity required only morphological analysis until the World Health Organization classification of central nervous system (CNS) tumors was revised, and now genetic analysis is necessary. We report a case of medulloepithelioma in the posterior cranial fossa that was diagnosed by both morphological and genetic analyses based on this classification. A 10-month-old girl was admitted to our hospital with consciousness disturbance and vomiting. Neuroimaging revealed a partially calcified mass and cyst formation in the posterior cranial fossa. Partial resection of the tumor was performed and histological findings revealed multilayered rosettes with LIN28A staining, but genetic analysis showed no amplification of the C19MC microRNA cluster at 19q14.32. Therefore, we diagnosed the tumor as medulloepithelioma belonging to other CNS embryonal tumors. The patient was immediately treated with systemic high-dose chemotherapy. Follow-up neuroimaging 10 months later showed no signs of recurrence. Medulloepitheliomas are difficult to diagnose by routine HE staining and require combined morphological, immunohistochemical and genetic analyses to provide an accurate diagnosis.

Prospective observational study of carbon-ion radiotherapy for non-squamous cell carcinoma of the head and neck.

To evaluate the efficacy and safety of carbon-ion radiotherapy for non-squamous cell carcinoma of the head and neck, 35 patients were enrolled in this prospective study. The primary end-point was the 3-year local control rate, and the secondary end-points included the 3-year overall survival rate and adverse events. Acute and late adverse events were evaluated according to the Common Terminology Criteria for Adverse Events, version 4.0. The median follow-up time for all patients was 39 months. Thirty-two and three patients received 64.0 Gy (relative biological effectiveness) and 57.6 Gy (relative biological effectiveness) in 16 fractions, respectively. Adenoid cystic carcinoma was dominant (60%). Four patients had local recurrence and five patients died. The 3-year local control and overall survival rates were 93% and 88%, respectively. Acute grade 2-3 radiation mucositis (65%) and dermatitis (31%) was common, which improved immediately with conservative therapy. Late mucositis of grade 2, grade 3, and grade 4 were observed in 11, one, and no patients, respectively. There were no adverse events of grade 5. Carbon-ion radiotherapy achieved excellent local control and overall survival rates for non-squamous cell carcinoma. However, the late mucosal adverse events were not rare, and meticulous treatment planning is required. Trial registration no. UMIN000007886.