Central neurocytoma with unusually intense FDG uptake: Case report

Central neurocytoma is a benign neuronal tumor with a favorable prognosis. This tumor is typically characterized by decreased uptake of 18F-fluorodeoxy glucose (FDG) and any increased uptake of FDG in patients suffering from this tumor would be highly unusual. A case of central neurocytoma with an intense FDG uptake, combined with atypical histopathological features and a high proliferation index is reported in this paper. A 45-year-old male had a two months' history of right hemiweakness. Magnetic resonance (MR) imaging showed a large tumor in the right lateral ventricle. Positron emission tomography (PET) with FDG revealed high glucose metabolism in the tumor. The histological diagnosis was central neurocytoma with atypical features characterized by microvascular proliferation. The MIB-1 labeling index, ordinarily smaller than 2.0%, was 7.0%. Conventional radiotherapy, with a total dose of 50 Gy, was administered after the surgical treatment. The patient returned to his normal daily activities after the cessation of radiation therapy.     

Subependymoma of the lateral ventricle: a case report

We report a case of subependymoma of the right lateral ventricle in a 59-year-old man. CT revealed a mass lesion in the right lateral ventricle. No calcification was seen in the tumor, and the right lateral ventricle was dilated dominantly by the tumor. The tumor showed intermediate intensity on T1-weighted MR images and high intensity on T2-weighted MR images. On contrast study, the tumor showed heterogeneous enhancement. We suspected this to be a case of central neurocytoma, and surgical resection was performed. The histological diagnosis was subependymoma, but we considered it difficult to differentiate from astrocytoma, central neurocytoma, and ependymoma.     

脑室内中枢神经细胞瘤的治疗（附20例报告）

目的：分析脑室内中枢神经细胞瘤的临床表现及鉴别诊断,探讨合理的治疗方法。方法：回顾分析2000-01～2009-10收治20例中枢神经细胞瘤的临床资料,并对神经显微外科手术和放射治疗的效果进行初步比较。结果：肿瘤直径2.5～6.0cm,大部分伴有梗阻性脑积水,MRI示T1、T2均为不均匀的等信号或略高信号,有钙化、囊变和肿瘤血管所致的散在低信号区,造影强化程度不一。20例病例中,全切除12例,次全部分切除8例,肿瘤复发1例。结论：神经显微外科手术是中枢神经细胞瘤的首选治疗方法,放射治疗可提高次全切除的疗效及减少复发病例。     

中枢神经细胞瘤的影像学诊断

目的：探讨中枢神经细胞瘤的影像学诊断价值。方法：回顾性分析11例经病理证实的中枢神经细胞瘤患者的CT和MRI表现。结果：11例中枢神经细胞瘤均位于侧脑室前2/3、孟氏孔区,多呈不规则形,可见分叶,向两侧不对称生长,边界清晰,无或见有轻度脑水肿。CT多呈等或稍高密度阴影,其中可见囊变及钙化。MRI表现为T1WI呈等、稍低或稍高信号,T2WI呈等或稍高信号,肿块可见囊变、钙化或出血,CT和MRI增强扫描见病灶实性部分轻中度强化,囊变和钙化区无强化。结论：中枢神经细胞瘤的CT和MRI表现具备一定的特征性,有望在术前作出正确诊断。     

Single photon emission CT images in a case of intraventricular neurocytoma

Although Tc-99m HMPAO uptakes in various brain tumors have been reported, SPECT images of neurocytoma have not been described. The authors report a patient with intraventricular neurocytoma (IN) who demonstrated significant uptake of Tc-99m HMPAO and Tl-201 Cl before brain biopsy. Residual tumor after biopsy showed significant uptake of I-123 IMP on early SPECT images, but this uptake was decreased on delayed images. The three radionuclides seem to have different uptake mechanisms.     

中枢神经细胞瘤的CT与MRI诊断

目的:研究中枢神经细胞瘤(CNC)的CT与MRI影像特点,以提高对该病的认识。方法:回顾性分析经手术病理证实的CNC 5例,分析其临床CT与MRI表现。结果:本组病例中肿瘤均位于侧脑室透明隔,靠近Monro孔处,在CT上呈等或稍高密度,在MRI T1WI呈等或稍低信号,T2WI上呈不均匀高信号,增强后可见不均匀明显强化。肿瘤均可见囊变,边缘清晰。结论:青年人位于透明隔的肿瘤,应考虑CNC的诊断,CT与MRI有助于诊断此病,确定手术方案。     

中枢神经细胞瘤的影像学误诊分析

目的:研究中枢神经细胞瘤的影像表现,分析误诊原因,以期提高认识和诊断水平。方法:搜集41例经手术病理证实的中枢神经细胞瘤,分析影像学误诊原因,探讨其诊断及鉴别诊断。结果:中枢神经细胞瘤是中枢神经系统少见的良性肿瘤,本组41例中误诊19例,以误诊为室管膜瘤最多(13例),其次为少枝胶质瘤或胶质瘤5例,尚有1例误诊为脉络膜乳头状瘤;只有定位诊断者17例,而正确诊断者仅5例。结论:中枢神经细胞瘤具有一定的影像学特征,仔细分析其影像学表现可以避免误诊。     

中枢神经细胞瘤的影像诊断(附3例报告并文献复习)

目的 探讨中枢神经细胞瘤(CNC)的CT和MRI诊断价值。资料与方法 回顾性分析经手术病理证实的3例CNC的CT和MRI表现。结果 2例位于侧脑室体部均来源于透明隔，分别向一侧或两侧侧脑室内生长，CT为混杂密度，其中1例可见钙化，MRI为混杂信号，不均匀较明显强化。1例位于左侧颞叶，CT可见钙化，MRI可见囊变及环形强化，占位效应不明显。结论 CNC是少见的颅内肿瘤，其发病年龄、部位及CT与MRI表现具有相对特征性表现。     

MRI对侧脑室肿瘤的鉴别诊断

目的 提高MRI对侧脑室不同肿瘤的鉴别诊断水平.方法 搜集侧脑室不同肿瘤22例,其中脑膜瘤6例,星形细胞瘤3例,室管膜瘤2例,中枢神经细胞瘤2例,脉络丛乳头状瘤、少突胶质细胞瘤、室管膜下巨细胞型星形细胞瘤、生殖细胞瘤及肠源性囊肿各1例,转移瘤4例,回顾性分析其MRI表现及其临床特点.结果 本组中所有脑膜瘤及脉络丛乳头状瘤均发生于侧脑室三角部,全部中枢神经细胞瘤(2例)、室管膜下巨细胞型星形细胞瘤(1例)均发生于室间孔区及侧脑室前部;6例脑膜瘤及4例转移瘤均发生于30岁以上,1例脉络丛乳头状瘤7岁,2例中枢神经细胞瘤年龄分别为23岁、24岁.6例脑膜瘤增强后呈明显均匀强化,2例中枢神经细胞瘤内可见多发囊变区,其中1例可见多发流空血管影,1例少突胶质细胞瘤内可见多发钙化灶,1例(1/3)星形细胞瘤可见瘤内出血.结论 侧脑室肿瘤的MRI表现特点为其鉴别诊断的重要依据,肿瘤部位、发病年龄特征对于鉴别诊断也有一定参考价值.     

中枢神经细胞瘤的MR影像特征分析

目的:探讨中枢神经细胞瘤的MRI征象。方法:回顾性分析9例经手术和病理证实的中枢神经细胞瘤的MRI征象。结果:9例肿瘤中6例位于侧脑室前部Monro孔附近,1例位于右侧侧脑室体后部,1例位于三脑室,1例位于右侧额叶。9例病变均为囊实性,T1WI病变实性部分呈等或略低信号,囊性部分呈低信号;T2WI实性部分呈等或高信号,囊性部分呈高信号。囊性部分表现为肿瘤边缘或内部多发的蜂窝状改变,5例实性部分DWI呈高信号;增强扫描病变实性部分呈明显或中度强化。结论:结合MR影像学及病理表现,有助于明确中枢神经细胞瘤的诊断。     

Gamma knife radiosurgery of recurrent atypical neurocytoma

Background and purpose

The goal of this work was to demonstrate the efficacy of stereotactic gamma knife radiosurgery (GKRS) for the treatment of neurocytoma by means of a case report and a comprehensive literature review.

Case report

A locally recurrent atypical neurocytoma in the area of the left third ventricle thalamic wall occurring 7?years after primary microsurgical resection in a 59-year old woman was treated by GKRS. A marginal dose of 17?Gy was delivered to the surrounding 50% isodose. At the last follow-up, 82?months after radiosurgery, the tumor was locally controlled. For the literature review, computerized bibliographic searches of Pubmed were supplemented with hand searches of reference lists and abstracts of ASCO/ASTRO/ESTRO meetings.

Discussion

The present case confirms the results of the literature analysis. From 1997–2011, a total of 14?series were published providing results of GKRS in 86?patients (89?lesions). The marginal doses, which have been applied, ranged from 9.6–20.0?Gy. With median follow-up intervals between 6 and 185?months, local control was 97.2% and local tumor progression of neurocytoma after GKRS was restricted to only 4?cases. In accordance with our own experience, GKRS was not associated with a relevant early or late toxicity.

Conclusion

GKRS can be assumed to be a safe and effective treatment modality of recurrent or residual neurocytoma.     

中枢神经细胞瘤的MRI表现

目的:探讨中枢神经细胞瘤的MRI表现及其诊断价值。材料和方法:对5例经手术和病理证实的中枢神经细胞瘤行常规MR成像(其中3例行增强扫描)。常规HE染色及免疫组织化学检查。结果:MRI显示肿瘤均位于侧脑室内,4例呈边界较清楚的不规则形团块,1例呈边界清楚的分叶状团块。肿瘤均以实性部分为主,伴有多发囊性变。实性部分呈长T1、长T2信号,囊性部分呈更长T1、更长T2信号,瘤体内(3例)及其边缘(2例)可见条状短T1高信号,3例肿瘤实性部分呈明显或中等增强。5例肿瘤均与透明隔及胼胝体有密切关系且表现为侧脑室扩大及梗阻性脑积水。免疫组织化学均显示神经元特异性烯醇化酶(NSE)及突触素(SYN)阳性。结论:中枢神经细胞瘤MRI表现具有一定的特征性,结合临床资料可提示诊断,确诊仍依靠病理学诊断。     

Alanine peak in central neurocytomas on proton MR spectroscopy

Introduction We present three consecutive patients with central neurocytoma in whom proton MRS demonstrated the presence of alanine. Materials and methods Three patients in the age range 24 to 30 years underwent MRI and proton MRS using a 1.5-T system. MRS was performed with the multivoxel PRESS sequence. All three patients underwent surgery and the diagnosis of central neurocytoma was established by histopathological examination and immunostaining. Results With an echo time of 135 ms glycine, high choline, small NAA and alanine were observed in all three patients. Conclusion Alanine may be observed in central neurocytomas as it is in meningiomas. Other spectral peaks such as those for glycine and NAA should help to identify this tumor correctly.     

Recently established entities of central nervous system tumors: review of radiological findings

Several new entities of central nervous system tumors have been established in the past decade. By reviewing our cases and previous reports, we describe 4 neuronal and mixed neuronal-glial tumors (papillary glioneuronal tumor, extraventricular neurocytoma, rosette-forming glioneuronal tumor of the fourth ventricle, and glioneuronal tumor with neuropil-like islands), angiocentric glioma and papillary tumor of the pineal region, with an attempt to explain the pathological basis of the imaging features.     

Central neurocytoma with craniospinal dissemination.

We report a case of central neurocytoma that manifested tumor recurrence with craniospinal dissemination. Imaging studies before surgery showed a markedly enhanced tumor with small cysts and calcification, which invaded the adjacent brain parenchyma, located in the posterior horn of the right lateral ventricle. Proton MR spectroscopy showed markedly elevated choline and lactate peaks with a strongly diminished N-acetylaspartate peak. Two years after neurosurgical intervention, the tumor showed multiple craniospinal dissemination in the middle cranial fossa and the intradural extramedullary space of the spine.     

颅内中枢神经细胞瘤高场MRI诊断

目的:分析颅内中枢神经细胞瘤的MRI影像学特征,为临床诊疗提供影像学依据.方法:回顾性分析12例中枢神经细胞瘤的MRI表现及临床诊疗过程,并结合文献分析其临床影像学特征.结果:12例中枢神经细胞瘤中,10例位于侧脑室内前2/3,1例位于右侧额叶,1例位于第四脑室内.在MRI T1WI上,中枢神经细胞瘤呈等信号或低信号,T2WI 上呈稍高信号,可见明显血管流空影.10例病例均行肿瘤全切术,2例行肿瘤次全切除术;9例病例术后均行放疗.随访1年,无复发.结论:中枢神经细胞瘤主要位于侧脑室内,也可位于脑实质或第四脑室内.侧脑室内前2/3肿瘤,尤其是透明隔的肿瘤,应考虑中枢神经细胞瘤的可能,MRI 有助于鉴别诊断.     

神经元和混合性神经元-神经胶质肿瘤的MRI表现

目的：提高对神经元和混合性神经元-神经胶质肿瘤的影像特征的认识。方法：回顾性分析11例经手术病理证实的神经元和混合性神经元-神经胶质肿瘤病例的影像学资料及临床资料。结果：3例中枢神经细胞瘤均发生于侧脑室内,瘤体呈囊实性,1例伴不规则钙化,增强扫描示肿瘤实质明显强化。2例脑室外神经细胞瘤,1例位于基底节区,瘤体呈实性伴部分钙化,增强后呈不均匀强化;1例发生于颈髓,肿瘤内有液化坏死,增强后轻度强化。3例节细胞胶质瘤,病变均呈囊实性混杂信号,瘤体实质部分明显不均匀强化。3例节细胞瘤,病变均为实性,信号均匀或混杂,增强扫描示肿瘤呈轻度～明显强化。结论：神经元和混合性神经元-神经胶质肿瘤的影像学表现有一定的特征性,结合临床病史综合分析能提高术前诊断准确性。     

Hyperacute changes in glucose metabolism of brain tumors after stereotactic radiosurgery: a PET study.

Cultured tumor cells show a marked increase in deoxyglucose uptake as early as 3 h after single high-dose irradiation, reflecting hyperacute response of the cells to noxious intervention. To evaluate the hyperacute effect of high-dose irradiation on tumor glucose metabolism in vivo, we measured 2-[18F]fluoro-2-deoxy-D-glucose (FDG) tumor uptake before and immediately after stereotactic radiosurgery. METHODS: A total of 19 brain tumors (17 metastatic and 2 primary, a meningioma and a central neurocytoma) in eight patients were treated with stereotactic radiosurgery. The received dose was between 24 and 32 Gy delivered to the central target point in the tumor. FDG PET was performed within 1 wk before radiosurgery and again 4 h after treatment. The net influx constant (Ki) was calculated on a pixel-by-pixel basis using graphical analysis, and the Ki ratio of tumor to ipsilateral cerebellum was used as an index of FDG uptake of the tumor. RESULTS: Eighteen of 19 irradiated tumors, all metastatic tumors and the meningioma, showed a 29.7% +/- 14.0% increase in the Ki ratio, which was significantly higher than that of nonirradiated tumors (4.1% +/- 3.6%, n = 8, P < 0.0001, analysis of variance). In metastatic tumors, an increase in the Ki ratio was significantly correlated with a decrease in the size of the irradiated tumors, as revealed by follow-up with CT or MRI (r = 0.61, P = 0.012, simple regression). The meningioma did not show a significant decrease in size, probably due to the short follow-up period. The central neurocytoma did not show any change in the Ki ratio or in tumor size. CONCLUSION: Serial FDG PET could be a potential tool for predicting the outcome of radiosurgery for brain tumors by detecting hyperacute changes in tumor glucose metabolism.     

中枢神经细胞瘤二例的磁共振成像诊断并文献复习简

目的：探讨中枢神经细胞瘤（CNC）的磁共振MRI特征,提高对本病的认识。方法回顾性分析2例经手术、病理证实的CNC的MRI特点。结果2例肿瘤均位于侧脑室及透明隔区域,邻近透明隔近室间孔（Monro孔）,分别向一侧或两侧侧脑室内生长。2例病变在T1WI和T2WI序列上呈混杂信号伴多发小囊变区,并夹杂少许小斑点状长T1短T2信号（钙化）;其中1例病变周边可见血管流空影;增强扫描呈轻-中度不均匀强化。结论中青年患者Monro孔区域富血供占位性病变伴多发小囊变、钙化、周边流空影,应高度怀疑中枢神经细胞瘤。     

侧脑室中枢神经细胞瘤的MRI诊断

目的探讨中枢神经细胞瘤(central neurocytoma,CNC)的MRI特点,以提高诊断准确性。资料与方法回顾性分析5例经手术病理证实的侧脑室CNC的MRI表现,4例行MRI平扫与增强,1例仅行MRI平扫。其中男2例,女3例。年龄18～39岁,平均29.2岁。结果5例CNC多呈类圆形或不规则形肿块,边界较清。T1WI表现为等低信号,T2WI呈等高混杂信号;3例可见流空血管信号。增强扫描肿瘤呈轻度或中度不均匀强化。5例肿瘤中4例位于侧脑室透明隔和室间孔,其中1例突入第三脑室;1例位于侧脑室体部及后角。结论侧脑室CNC具有一定的MRI特点,结合其好发部位、发病年龄等可以提高其诊断的准确性。