著者

Takaharu KAWAJIRI Hayato TAKEUCHI Yoshinobu TAKAHASHI Yuji SHIMURA Junya KURODA Naoya HASHIMOTO

出版者

The Japan Neurosurgical Society

雑誌

NMC Case Report Journal (ISSN:21884226)

巻号頁・発行日

vol.10, pp.131-137, 2023-12-31 (Released:2023-05-17)

参考文献数

22

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Eating disorders caused by brain tumors are infrequently seen. Recent studies revealed that a neurocircuit from the nucleus tractus solitarius of the medulla oblongata to the hypothalamus participates in the control of appetite. Among brain tumors, those located in the brain stem, especially a solitary one in the medulla oblongata, are rare. Tumors in the brainstem are generally considered gliomas, and with the difficulty in reaching the lesion, treatment without histological confirmation is often performed. However, there are a few reported cases of medulla oblongata tumors other than gliomas. We describe a case of a 56-year-old man who presented with persistent anorexia. Magnetic resonance images revealed a solitary tumor in the medulla oblongata. After several examinations, craniotomy for the biopsy of the tumor using the cerebellomedullary fissure approach was carried out and primary central nervous system lymphoma (PCNSL) was histologically proven. The patient was treated with effective adjuvant therapy and was discharged home after he recovered from the symptoms. No tumor recurrence was recognized 24 months after surgery. A PCNSL arising only from the medulla oblongata is very rare, and anorexia can be an initial symptom of a tumor in the medulla oblongata. Surgical intervention is safely achieved and is a key to a better clinical outcome.

著者

Masaharu Oshima Daisuke Mori Aki Takigawa Akihiko Otsuki Naoka Nagamura Shun Konno Yoshinobu Takahashi Masato Kotsugi Hiroshi Nohira

出版者

The Japan Society of Vacuum and Surface Science

雑誌

e-Journal of Surface Science and Nanotechnology (ISSN:13480391)

巻号頁・発行日

vol.16, pp.257-261, 2018-06-09 (Released:2018-06-09)

参考文献数

21

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SiC trench structures having a width of 0.6 μm and a depth of 2.0 μm are fabricated by reactive ion etching (RIE) using a gas mixture of SF6, Ar, and O2. Further, SiC trench structures are cleaved to expose the sidewall for the channel region of a trench MOSFET. These structures were analyzed by pin-point photoelectron spectroscopy using a 100 nm soft-X-ray beam. It is observed that around 2 nm-thick homogeneous carbon-rich layer containing 1—2% F forms on the SiC sidewalls. This may be caused due to the re-deposition of RIE reaction products, CF4 and SiF4, under appropriate conditions to fabricate the trench walls that are approximately vertical using RIE. Further, a carbon-rich layer having a thickness of about 2.4 nm is also formed on the bottom of the SiC trench, suggesting the possibility of selective etching of Si from the SiC substrates. The position of the dominant peak that is associated with the SiC component remains constant regardless of the trench depth, suggesting homogeneous band bending due to the RIE defects, which may explain the reason for no variation being observed in the gate oxide/SiC interface trap density values. Further, the band bending of 1.50 eV that is observed on the sidewall can be attributed to a positively charged carbon vacancy (VC+). [DOI: 10.1380/ejssnt.2018.257]

著者

Hayato TAKEUCHI Yoshinobu TAKAHASHI Seisuke TANIGAWA Takanari OKAMOTO Yoshinori KODAMA Yukiko SHISHIDO-HARA Ema YOSHIOKA Tomoko SHOFUDA Yonehiro KANEMURA Eiichi KONISHI Naoya HASHIMOTO

出版者

The Japan Neurosurgical Society

雑誌

NMC Case Report Journal (ISSN:21884226)

巻号頁・発行日

vol.9, pp.199-208, 2022-12-31 (Released:2022-07-08)

参考文献数

26

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Despite recent signs of progress in diagnostic radiology, it is quite rare that a glioblastoma (GBM) is detected asymptomatically. We describe two patients with asymptomatic nonenhancing GBMs that were not diagnosed with neoplasia at first. The patients had brain scans as medical checkups, and incidentally lesions were detected. In both cases, surgical specimens histopathologically showed no evidence of neoplasia, whereas molecular genetic findings were isocitrate dehydrogenase (IDH) -wildtype, O6-methylguanine-DNA methyltransferase promoter (pMGMT) unmethylated, and telomerase reverse transcriptase (TERT) promoter mutated, which matched to GBM. One patient was observed without adjuvant therapy and the tumor recurred 7 months later. Reoperation was performed, and histopathologically GBM was confirmed with the same molecular diagnosis as the first surgical specimen. Another patient was carefully observed, and chemoradiotherapy was begun 6 months after the operation following the extension of the lesion. Eventually, because of disease progression, both patients deceased. We postulate that in each case, the tumor was not lower-grade glioma but corresponded to the early growth phase of GBM cells. Thus far, cases of malignant transformation from lower-grade glioma or asymptomatic GBM with typical histologic features are reported. Nevertheless, to the best of our knowledge, no such case of nonenhancing, nonhistologically confirmed GBM was reported. We conjecture these cases shed light on the yet unknown natural history of GBM. GBM can take the form of radiological nonenhancing and histological nonneoplastic fashion before typical morphology. Molecular genetic analysis can diagnose atypical preceding GBM, and we recommend early surgical removal and adjuvant treatment.

著者

Hayato TAKEUCHI Tohru INABA Yukiko SHISHIDO-HARA Taku TSUKAMOTO Shinsuke MIZUTANI Takanari OKAMOTO Seisuke TANIGAWA Takumi YAMANAKA Yoshinobu TAKAHASHI Eiichi KONISHI Junya KURODA Naoya HASHIMOTO

出版者

The Japan Neurosurgical Society

雑誌

Neurologia medico-chirurgica (ISSN:04708105)

巻号頁・発行日

pp.2023-0029, (Released:2023-10-18)

参考文献数

24

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Primary central nervous system lymphoma (PCNSL), a relatively rare brain tumor, bears a dire prognosis. On occasion, the rapid progression of the tumor makes immediate diagnosis and initiation of therapy imperative. To achieve swift diagnosis, we adopt flow cytometry (FCM) in addition to conventional histopathology. This study aimed to reveal the utility of FCM diagnosis for PCNSL and the cause of false-negative results of FCM diagnosis. We investigated 33 patients with suspected PCNSL on neuroradiological findings and received both FCM and histological diagnosis. The patients' electronic medical records were investigated, and histological findings, results of FCM, and other clinical data were evaluated. Overall, 27 patients (14 males and 13 females) were diagnosed with PCNSL by histological confirmation. The median age at diagnosis was 68 years. FCM analysis showed lymphoma pattern in 24 cases; however, FCM results did not show lymphoma pattern (sensitivity: 88.9%, specificity: 100%) in the other three lymphoma cases (FCM discordant: FCM-D) and six nonlymphomatous tumor cases. Analysis of FCM-D cases showed the infiltration of T lymphocytes or astrocytes into the tumor tissue, indicating tumor microenvironmental reaction; it is assumed that these reactions deceived FCM diagnosis. The survival of FCM-D patients was superior to FCM concordant counterpart, although the difference was not significant (p = 0.459). The diagnosis of PCNSL by FCM is rapid and highly reliable. Some FCM-D cases are PCNSLs with strong tumor microenvironmental reactions.