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  • Author or Editor: Mitsuhiro Hasegawa x
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Hironori Fujisawa, Mitsuhiro Hasegawa, Shinya Kida and Junkoh Yamashita

Object. It has been reported that due to premature synostosis of the lambdoid suture in the first 24 months of life, more than 70% of patients with Crouzon syndrome concurrently suffer from chronic tonsillar herniation (Chiari Type I malformation) and some (20%) associated syringomyelia. The goal of the present study was to examine mutations in the fibroblast growth factor receptor (FGFR) genes in Crouzon syndrome and its related conditions.

Methods. Five patients were studied: three with Crouzon syndrome (one sporadic and two familial), one with sporadic Chiari I with syringomyelia, and one with unilateral lambdoid synostosis. Deoxyribonucleic acid was screened for FGFR1–3 mutations by using single-strand conformational polymorphism and subsequent direct sequencing.

Two types of missense mutations were detected in the FGFR2 gene, Cys342Trp (1205, TGC → TGG) in a patient with sporadic Crouzon syndrome and Tyr281Cys (1021, TAC → TGC) in two siblings (brother and sister) with familial Crouzon syndrome, respectively. The former has been reported only in sporadic cases but the latter has not previously been identified. A polymorphism in the FGFR3 gene, Asn294Asn (882, AAT → AAC), was also detected in three patients. No mutation was found in the patient with sporadic Chiari I with syringomyelia.

Conclusions. The FGFR2 missense mutation was detected in Crouzon syndrome but not in sporadic Chiari I with syringomyelia or lambdoid synostosis. A novel FGFR2 mutation, Tyr281Cys, was found in familial Crouzon syndrome with Chiari I and syringomyelia. It may be informative to look for this in patients with Crouzon syndrome and associated syringomyelia.

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Katsuyoshi Miyashita, Yutaka Hayashi, Hironori Fujisawa, Mitsuhiro Hasegawa and Junkoh Yamashita

✓ Solitary fibrous tumor (SFT) is a benign and rare neoplasm. To date, only 37 patients with intracranial SFTs have been reported. Although a number of the tumors were recurrent and some later underwent malignant transformation, none of these lesions progressed to cerebrospinal fluid (CSF) dissemination. In this paper the authors report a case of SFT in which the lesion recurred several times and ultimately was disseminated by the CSF. The patient was a 63-year-old woman with multiple intracranial and spinal tumors. Fifteen years before this presentation, at the age of 48 she had been hospitalized for resection of a falcotentorial tumor. During the ensuing 15 years she underwent multiple surgeries and sessions of radiation therapy for recurrent lesions. The exclusive location of her tumors in the subarachnoid space at the end of this 15-year period indicate CSF dissemination of the tumor.

The tumor that was resected when the patient was 48 years old and the latest resected lesion were analyzed by performing immunohistological CD34, epithelial membrane antigen, vimentin, S100 protein, and reticulin staining, and determining the MIB-1 labeling index (LI). Most of the results were identical, and both tumors were diagnosed as SFT according to a staining pattern that showed a strong and diffuse positive reaction for CD34. Nevertheless, the authors noted that the MIB-1 LI increased from less than 1% in the original tumor to 13% in the latest tumor. The increased proliferation of MIB-1 indicates that the malignant transformation could have occurred during tumor recurrence with CSF dissemination.

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Yutaka Hayashi, Masayuki Iwato, Mitsuhiro Hasegawa, Osamu Tachibana, Andreas von Deimling and Junkoh Yamashita

✓ A gangliocytoma/ganglioglioma with no atypical or malignant features was subtotally resected from the right temporal lobe of a 16-year-old woman. A second resection was performed 8 years later to treat a locally recurrent lesion with increased cellularity that was diagnosed as a World Health Organization Grade II ganglioglioma on the basis of neuropathological examination. Molecular analysis of the recurrent tumor revealed a TP53 gene mutation, but no amplification of the epidermal growth factor receptor (EGFR) gene. Radiotherapy (60 Gy) was administered after the second resection. The patient returned 1 year later with a second focal recurrence. The specimen obtained during the third resection of tumor exhibited exclusively astrocytic differentiation, cellular pleomorphism with multinucleated cells, high mitotic activity, and endothelial proliferation. Therefore, the tumor was diagnosed to be a glioblastoma multiforme (GBM). Molecular analysis of tumor DNA from the second recurrent tumor demonstrated the presence of the TP53 mutation, which previously had been observed in the first recurrent tumor, but again no evidence of EGFR amplification. Findings demonstrate that the presence of TP53 mutation in progressed gangliogliomas should be interpreted as a progression-associated mutation rather than a consequence of treatment. This is the first report to indicate that the molecular pathways of gangliocytomas/gangliogliomas progressing to become GBMs may parallel those of diffuse astrocytomas progressing to become GBMs.

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Mitsuhiro Hasegawa, Junkoh Yamashita, Tetsumori Yamashima, Kiyonobu Ikeda, Yoshie Fujishima and Masahide Yamazaki

✓ Antiphospholipid antibodies have been reported to occur in ischemic stroke patients, but there have been no previous reports linking these antibodies to spinal cord infarction. A case of spinal cord infarction associated with primary antiphospholipid syndrome in a 6-year-old boy is reported. Magnetic resonance imaging clearly demonstrated marked swelling of the thoracolumbar spinal cord with gadolinium-diethylenetriamine pentaacetic acid enhancement at an acute stage, followed later by cord atrophy. Serological study disclosed positive lupus anticoagulant and immunoglobulin G anticardiolipin antibody. It is suggested that the role of antiphospholipid antibodies as an etiological factor for spinal cord ischemia should be recognized among causes that might have been categorized as either spontaneous spinal cord infarction or myelitis.

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Yayoi Kamakura, Mitsuhiro Hasegawa, Toshinari Minamoto, Junkoh Yamashita and Hironori Fujisawa

Object

Of the intracranial germ cell tumors (IGCTs), 10% of germinomas and most nongerminomatous tumors remain refractory to multimodality therapy. The authors investigated the mutation of c-kit and the expression of its product KIT in IGCTs to identify tumors susceptible to imatinib mesylate, a synthetic agent targeting KIT.

Methods

The authors investigated 26 IGCTs, including 13 germinomas, five mixed germ cell tumors (MGCTs), four immature teratomas (ITs), and two each of yolk sac tumors and choriocarcinomas. These tumors were examined for the expression of KIT and CD34 by immunohistochemical analysis, and for mutations in exons 2, 8 to 11, 13, and 17 of c-kit. Strong KIT expression was found in the cell membrane of germinomas (100%) and germinomatous cells of MGCTs (80%), as well as in the cytoplasm of epithelial and smooth-muscle cells of ITs. The membranous expression of CD34 was found in the nongerminomatous tumor cells and the chondrocytes of MGCTs (60%), ITs (100%), and a choriocarcinoma (50%), but not in germinomas and germinomatous cells. A total of five missense mutations distributed in exons 2, 11, 13, and 17 of c-kit were detected in three (23%) of the 13 germinomas. The novel mutations E73K, T96M (both in exon 2), and A636V (in exon 13) were detected in a single tumor. The presence or type of c-kit mutation was not correlated with patient prognosis.

Conclusions

Immunohistochemical analysis of KIT expression is useful for the diagnosis of germinoma. This study may help in clarifying the pathogenesis of IGCTs and in identifying tumors susceptible to drugs targeting KIT.

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Sotaro Higashi, Kazuya Futami, Hiroshi Matsuda, Junkoh Yamashita, Masaaki Hashimoto, Mitsuhiro Hasegawa, Kazuhiko Tokuda, Mahmood Hassan and Kinichi Hisada

✓ The present study was performed to investigate the effects of head elevation on intracranial hemodynamics in patients with ventriculoperitoneal (VP) shunts. The series included 35 hydrocephalic patients and five individuals without hydrocephalus who were used as controls. The hydrocephalic patients were divided into three groups: 15 patients who received VP shunts with a differential-pressure valve (DP group); 11 who received VP shunts with a variable-resistance valve (VR group), and 13 hydrocephalic patients (Hyd group) who had not received shunts (four underwent VP shunts later).

The cerebral blood flow (CBF) of patients in the supine and upright positions was measured by technetium-99m hexamethylpropylenamine oxide (HMPAO) single-photon emission computerized tomography in each patient, using the subtraction technique. Cerebral perfusion pressure (CPP) was taken as the difference between the mean arterial blood pressure and ventricular fluid pressure, both referenced to the level of the foramen of Monro. The patients' heads were elevated stepwise from supine to upright. Percent changes of the mean CBF in the upright position (%ΔmCBFupr) were 24.9% ± 4.3% (mean ± standard error of the mean) in the DP group, 6.2% ± 2.7% in the VR group, 3.5% ± 2.6% in the Hyd group, and 4.5% ± 2.2% in the control group. Patients in the DP group showed a pathological increase in CPP with head elevation, whereas those in the Hyd and VR groups showed a physiological decrease in CPP. Three patients with differential-pressure valves, whose %ΔmCBFupr was markedly high, developed low-intracranial pressure syndrome. In conclusion, shunted patients with a DP valve showed pathological intracranial hemodynamics in the upright position. This pathological hemodynamic stress in patients with long-standing differential-pressure valve implantation may induce pathological changes in the brain such as subependymal gliosis.

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Hironori Fujisawa, Kohei Marukawa, Mitsuhiro Hasegawa, Yasuo Tohma, Yutaka Hayashi, Naoyuki Uchiyama, Osamu Tachibana and Junkoh Yamashita

Object. Because of their histological similarities, it is occasionally difficult to differentiate neurocytoma and dysembryoplastic neuroepithelial tumor (DNT) from oligodendroglial tumors. This study was conducted to investigate genetic differences among these tumor types in terms of loss of heterozygosity on chromosomes 1p and 19q, and p53 gene mutation.

Methods. A total of 24 tumors were analyzed, consisting of eight central neurocytomas, three DNTs, seven oligodendrogliomas, four oligoastrocytomas, and two undetermined extraventricular tumors with neurocytoma features (ETNFs). Allelic loss was determined using microsatellite markers that cover the common deletions on chromosomes 1p and 19q in oligodendrogliomas. A p53 gene mutation was identified using polymerase chain reaction—single-strand conformation polymorphism analysis and subsequent direct sequencing. Immunohistochemical studies with synaptophysin and electron microscopy investigations were also conducted. Allelic loss on 1p and 19q was detected in six oligodendrogliomas (86%) and in three oligoastrocytomas (75%), but in none of the central neurocytomas or DNTs. A p53 missense mutation was detected at codon 161 (GCC→ACC, Ala→Thr) in only one oligoastrocytoma without allelic loss. Synaptophysin was expressed in all central neurocytomas and DNTs, in three oligodendrogliomas (43%), and in three oligoastrocytomas (75%). Of the ETNFs, one demonstrated synaptophysin expression and neural ultrastructures but lacked genetic alterations, whereas the other showed allelic loss on 1p and 19q but was negative immunohistochemically and ultrastructurally. The former was diagnosed as a potential intraparenchymal neurocytoma and the latter as an oligodendroglioma.

Conclusions. Despite histological similarities, central neurocytomas and DNTs are genetically distinct from oligodendroglial tumors. Examination for allelic loss on 1p and 19q and for p53 mutation can be useful for making this distinction.

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Koichi Misaki, Kohei Marukawa, Yutaka Hayashi, Toshio Fukusato, Toshinari Minamoto, Mitsuhiro Hasegawa, Junkoh Yamashita and Hironori Fujisawa

Object. Medulloblastoma is a malignant cerebellar tumor of childhood and is difficult to cure due to frequent cerebrospinal fluid dissemination. Amplification of the c-myc gene (4%) and messenger (mRNA) overexpression (50%) are known to be adverse prognostic indicators. Because mRNA overexpression cannot be explained by gene amplification alone, mechanisms other than gene amplification are postulated. Molecules on the Wnt signal pathway in primary tumors were examined.

Methods. Immunohistochemical and cytogenetic examinations of β- and γ-catenin, c-myc, N-myc, and cyclin D1 in 24 primary medulloblastomas were conducted, and their clinical relevance was evaluated. Cytoplasmic/membranous staining of β- and γ-catenin was detected in 19 (79%) and nine (37%) cases, respectively, and nuclear expression of cyclin D1 and c-myc was detected in six (25%) and 21 (83%) cases, respectively. The expression levels of γ-catenin in Western blot analysis and immunohistochemistry were similar. By differential polymerase chain reaction, c-myc and N-myc were amplified separately in two large cell/anaplastic medulloblastomas. No cyclin D1 amplification, or β- or γ-catenin mutations were found. Kaplan—Meier analysis revealed no dissemination at diagnosis (Chang Grade M0) and γ-catenin expression was correlated with good prognosis (p = 0.0002 and 0.003, respectively). Expression of γ-catenin was also significant in the M0 group (p = 0.022). Expression of cyclin D1 showed a trend toward adverse outcome (p = 0.057) and all patients in whom cyclin D1 expression was found died of disease.

Conclusions. Expression of γ-catenin is of great prognostic value and its immunohistochemistry may be useful for further stratification of treatment. Cyclin D1 expression may have the potential to be an adverse prognostic indicator.

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Koichi Misaki, Kohei Marukawa, Yutaka Hayashi, Toshio Fukusato, Toshinari Minamoto, Mitsuhiro Hasegawa, Junkoh Yamashita and Hironori Fujisawa

Object

Medulloblastoma is a malignant cerebellar tumor of childhood and is difficult to cure due to frequent cerebrospinal fluid dissemination. Amplification of the c-myc gene (4%) and messenger (mRNA) overexpression (50%) are known to be adverse prognostic indicators. Because mRNA overexpression cannot be explained by gene amplification alone, mechanisms other than gene amplification are postulated. Molecules on the Wnt signal pathway in primary tumors were examined.

Methods

Immunohistochemical and cytogenetic examinations of β- and γ-catenin, c-myc, N-myc, and cyclin D1 in 24 primary medulloblastomas were conducted, and their clinical relevance was evaluated. Cytoplasmic/membranous staining of β- and γ-catenin was detected in 19 (79%) and nine (37%) cases, respectively, and nuclear expression of cyclin D1 and c-myc was detected in six (25%) and 21 (83%) cases, respectively. The expression levels of γ-catenin in Western blot analysis and immunohistochemistry were similar. By differential polymerase chain reaction, c-myc and N-myc were amplified separately in two large cell/anaplastic medulloblastomas. No cyclin D1 amplification, or β- or γ-catenin mutations were found. Kaplan—Meier analysis revealed no dissemination at diagnosis (Chang Grade M0) and γ-catenin expression was correlated with good prognosis (p = 0.0002 and 0.003, respectively). Expression of γ-catenin was also significant in the M0 group (p = 0.022). Expression of cyclin D1 showed a trend toward adverse outcome (p = 0.057) and all patients in whom cyclin D1 expression was found died of disease.

Conclusions

Expression of γ-catenin is of great prognostic value and its immunohistochemistry may be useful for further stratification of treatment. Cyclin D1 expression may have the potential to be an adverse prognostic indicator.