Pediatric-type high-grade gliomas with PDGFRA amplification in adult patients with Li-Fraumeni syndrome: clinical and molecular characterization of three cases.

Li-Fraumeni syndrome (LFS) is an autosomal dominant tumor predisposition syndrome caused by heterozygous germline mutations or deletions in the TP53 tumor suppressor gene. Central nervous system tumors, such as choroid plexus tumors, medulloblastomas, and diffuse gliomas, are frequently found in patients with LFS. Although molecular profiles of diffuse gliomas that develop in pediatric patients with LFS have been elucidated, those in adults are limited. Recently, diffuse gliomas have been divided into pediatric- and adult-type gliomas, based on their distinct molecular profiles. In the present study, we investigated the molecular profiles of high-grade gliomas in three adults with LFS. These tumors revealed characteristic histopathological findings of high-grade glioma or glioblastoma and harbored wild-type IDH1/2 according to whole exome sequencing (WES). However, these tumors did not exhibit the key molecular alterations of glioblastoma, IDH-wildtype such as TERT promoter mutation, EGFR amplification, or chromosome 7 gain and 10 loss. Although WES revealed no other characteristic gene mutations or copy number alterations in high-grade gliomas, such as those in histone H3 genes, PDGFRA amplification was found in all three cases together with uniparental disomy of chromosome 17p, where the TP53 gene is located. DNA methylation analyses revealed that all tumors exhibited DNA methylation profiles similar to those of pediatric-type high-grade glioma H3-wildtype and IDH-wildtype (pHGG H3-/IDH-wt), RTK1 subtype. These data suggest that high-grade gliomas developed in adult patients with LFS may be involved in pHGG H3-/IDH-wt. PDGFRA and homozygous alterations in TP53 may play pivotal roles in the development of this type of glioma in adult patients with LFS.

CD79B Y196 mutation is a potent predictive marker for favorable response to R-MPV in primary central nervous system lymphoma.

BACKGROUND: Rituximab, high-dose methotrexate (HD-MTX), procarbazine and vincristine (R-MPV), has significantly prolonged the survival of patients with primary central nervous system lymphoma (PCNSL), but predictive factors for response to R-MPV have not yet been investigated. Herein, we investigated the correlation of MYD88 L265P and CD79B Y196 mutations, which are the most frequently found molecular alterations in PCNSL, with prognosis of patients with PCNSL treated with R-MPV. METHODS: We investigated the long-term clinical course and status of MYD88 and CD79B genes in 85 patients with PCNSL treated with R-MPV or HD-MTX treatment, and the correlation of these genetic mutations with prognosis. RESULTS: R-MPV achieved an excellent tumor control rate (61.6% and 69.9% of 5-year progression-free and overall survival rates, respectively). While MYD88 L265P mutation had no significant effect on survival, patients with CD79B Y196 mutations exhibited prolonged survival (p < 0.05). However, the association of CD79B Y196 mutation with a better prognosis was not observed in the HD-MTX cohort, which indicated that CD79B Y196 mutation was a predictive marker for a favorable response to R-MPV. Furthermore, we established an all-in-one rapid genotyping system for these genetic mutations. CONCLUSIONS: In conclusion, CD79B Y196 mutation is a potent predictive marker for favorable response to R-MPV in PCNSL. The rapid identification of MYD88 L265P and CD79B Y196 mutations can be helpful not only for the accurate molecular diagnosis of PCNSL but also for the prediction of response to R-MPV.

Brain metastasis from extramammary Paget's disease.

Herein, we present a case of extramammary Paget's disease with brain metastasis that was diagnosed pathologically for the first time in Japan. Moreover, invasive extramammary Paget's disease (with distant metastasis) highly resistant to treatment. Only for brain metastasis, we may control the tumor by surgical resection and stereotactic radiosurgery (SRT) for the treatment of intracranial metastases was assessed. An 76-year-old man was diagnosed with extramammary Paget's disease of the vulva at nearby hospital. Surgical resection and sentinel lymph node dissection were then performed, and the patient received chemotherapy because multiple lymph node metastases were suspected. The patient's response to chemotherapy was poor, and he was in the state of Progressive Disease. He complained of dyslexia and was referred to another hospital when he was 81 years old. Plain magnetic resonance imaging (MRI) was conducted, and two brain tumors in the vicinity of the left cerebellar tent were suspected. In our hospital, gadolinium contrast-enhanced MRI was performed and showed a tumor in the cerebellum (left posterior temporal lobe) and another tumor under the tent (left cerebellar hemisphere). Significant edema was also noted. Based on these findings, the intracranial lesion was diagnosed as metastatic brain tumor. The pathological diagnosis was brain metastasis from extramammary Paget's disease. Postoperative intracranial residual disease was treated with stereotactic radiosurgery. MRI showed that the size of the cerebellar lesions decreased, and no recurrence of cerebral lesions was observed. SRT for extracranial lymph node metastases was performed. Mass reduction and SRT may be the best way to treat brain metastasis from extramammary Paget's disease.

Cerebrospinal fluid taurine after traumatic brain injury.

In the experimental setting, taurine is known to be released from swollen cells to reestablish their normal volume. However, its clinical relevance has not been fully understood. This study was undertaken to reveal changes in cerebrospinal fluid (CSF) amino acids concentration in patients with severe traumatic brain injury (TBI). The study included eight patients, in whom a ventricular catheter was inserted to measure intracranial pressure and obtain CSF samples for 5 days. CSF obtained from patients with normal pressure hydrocephalus served as a control. CSF taurine concentration increased 1.8 times control (P < 0.05) after TBI and returned to control value approximately 67 h after injury. Taurine decreased further and remained lower than control thereafter. Phosphoethanolamine showed similar increase, whereas glutamine decreased transiently and arginine remained close to control value. The present data support the period of astrocytic swelling observed after TBI in other morphological studies. The mechanism and consequences of CSF taurine decrease in the subacute stage of TBI need to be elucidated.