室管膜下巨細(xì)胞型星形細(xì)胞瘤( subependymal giant cell astrocytoma,SEGA)是一種相對少見的與結(jié)節(jié)性硬化相關(guān)的良性腫瘤,。2003年發(fā)表的歐洲SEGA診斷與治療建議中,專家組首次明確其定義:室間孔鄰近區(qū)域腫瘤直徑>5mm并可記錄到腫瘤生長,影像學(xué)可見的強(qiáng)化灶,。這一定義特別強(qiáng)調(diào)SEGA需要腫瘤生長的影像學(xué)證據(jù),且診斷標(biāo)準(zhǔn)明確為腫瘤直徑>5mm,而不是過去采用的>1cm

Subependymal giant cell astrocytoma (SEGA) is a relatively rare benign tumor associated with tuberous sclerosis. In the European SEGA diagnostic and treatment recommendations published in 2003, the expert group defined for the first time that tumors in the vicinity of the interventricular foraminium had a diameter of 5mm and could be recorded as tumor growth with enhanced radiographic foci. This definition emphasizes in particular that SEGA requires imaging evidence of tumor growth, and the diagnostic criteria are defined as tumor diameter of 5mm, instead of >1cm

結(jié)節(jié)性硬化癥是由TSC1或TSC2基因突變所致一種常染色體顯性遺傳的神經(jīng)皮膚綜合征,多有外胚葉組織的器官發(fā)育異常,可出現(xiàn)腦、皮膚,、周圍神經(jīng),、腎等多器官受累。臨床三大特征是面部皮脂腺瘤,、癲癇發(fā)作和智能減退,。中樞神經(jīng)系統(tǒng)病變主要包括皮質(zhì)結(jié)節(jié)、腦白質(zhì)異常,、室管膜下結(jié)節(jié)及SEGA,有5%~14%的結(jié)節(jié)性硬化癥患者的中樞神經(jīng)系統(tǒng)病變伴發(fā)SEGA,。SEGA多數(shù)伴有結(jié)節(jié)性硬化,國內(nèi)外與結(jié)節(jié)性硬化無關(guān)的散發(fā)病例僅有少數(shù)報道,不伴結(jié)節(jié)性硬化癥的孤立性SEGA缺少分子遺傳學(xué)檢測項目,此類患者究竟是臨床表現(xiàn)隱匿的結(jié)節(jié)性硬化癥還是真正的孤立性SEGA尚存在爭議。

Tuberous sclerosis is caused by TSC1 or TSC2 gene mutation, an autosomal dominant neurocutaneous syndrome. Most of them have abnormal organ development of ectodermal tissue, and multiple organs such as brain, skin, peripheral nerve and kidney may be involved. The three major clinical features are facial sebaceous adenoma, seizure and intellectual decline. Central nervous system lesions mainly include cortical nodules, white matter abnormalities, subependymal nodules and SEGA. SEGA occurs in 5%~14% of patients with tuberous sclerosis. Most SEGA patients are accompanied by tuberous sclerosis. Only a few sporadic cases unrelated to tuberous sclerosis have been reported at home and abroad. Isolated SEGA without tuberous sclerosis lacks molecular genetic testing items.

室管膜下巨細(xì)胞性星形細(xì)胞瘤( Subependymal giant cell astrocytoma,，SGCA)也是一種WHO I級星形細(xì)胞  ,與室管膜下錯構(gòu)性結(jié)節(jié)密切相關(guān),。病理學(xué)上腫細(xì)胞變化多樣,很難與錯構(gòu)性結(jié)節(jié)區(qū)分,可見大錐體細(xì)胞,是梭形或上皮樣,胞質(zhì)豐富,胞核圓而大,染色質(zhì)偏位,但很少間變  GFAP染色(+)SCCA僅見于1/5以下的TS病人,但一旦出現(xiàn),約1/4出現(xiàn)神經(jīng)系統(tǒng)癥狀,。最常見的臨床表現(xiàn)為抽搐,其他包括惡心嘔吐,、意識障礙等本病進(jìn)展慢,一般不侵犯腦實(shí)質(zhì),因此預(yù)后良好。阻 塞室間孔及并發(fā)出血者可致腦積水與猝死。

Subependymal giant cell astrocytoma (SGCA) is also a WHO grade I astrocytoma, which is closely related to the Subependymal giant cell astrocytoma (SGCA). Histopathologically, the swollen cells are diverse and difficult to distinguish from the dysplasia nodules. Large pyramidal cells, fusiform or epithelioid, are abundant in cytoplasm, with large round nuclei and skewed chromatin. The most common clinical manifestation is convulsive, other include disgusting vomiting, consciousness obstacle wait for this disease progress is slow, do not invade brain essence commonly, because this prognosis is good. Obstruction of interventricular orifice and hemorrhage may lead to hydrocephalus and sudden death.

SEGA主要由梭形細(xì)胞和大細(xì)胞兩種成分組成,二者混合存在:梭形細(xì)胞突起長并松散聚集成束狀,形成纖細(xì)的組織學(xué)背景;大細(xì)胞呈簇狀分布,形態(tài)似胖細(xì)胞,體積介于胖細(xì)胞和節(jié)細(xì)胞之間,灶性區(qū)域可見圍繞血管的假“菊形團(tuán)”樣結(jié)構(gòu),腫瘤細(xì)胞胞質(zhì)豐富呈毛玻璃樣,空泡狀胞核偏位于一側(cè),、核仁清晰;還可見散在分布,、體積更大的節(jié)細(xì)胞樣巨細(xì)胞和多核瘤巨細(xì)胞。SEGA增殖指數(shù)較低,鮮見核分裂象,、血管內(nèi)皮增生和壞死區(qū)。電鏡觀察,部分SEGA內(nèi)可見分泌顆粒和微管結(jié)構(gòu),。

SEGA is mainly composed of two components, spindle cells and large cells. The two components are mixed: spindle cells have long protrusions and gather loosely into bundles, forming a fine histological background. The large cells were clustered and distributed like fat cells, with a volume between fat cells and ganglion cells. The focal areas showed pseudo' pyretic '-like structures around the blood vessels. The tumor cells had abundant cytoplasm, which was like ground glass, with vacuolar nuclei on one side and clear nucleoli. There are also scattered and larger ganglion - like giant cells and multinucleated giant cells. The SEGA proliferation index was low, and mitosis, vascular endothelial hyperplasia and necrotic areas were rare. Under electron microscope, secretory granules and microtubules were observed in part of SEGA.

免疫組織化學(xué)檢查:腫瘤細(xì)胞彌漫表達(dá)S-100和 Vimentin,不同程度地表達(dá)GFAP,尤以梭形細(xì)胞成分為主;部分細(xì)胞可表達(dá)神經(jīng)元標(biāo)志物Syn,、NSE、NFP和β3-微管蛋白,。

Immunohistochemical examination showed that tumor cells diffusely expressed s-100 and Vimentin, and expressed GFAP to varying degrees, especially spindle cells. Some cells expressed neuronal markers Syn, NSE, NFP and beta 3- tubulin.

CT:SEGA常為邊界清楚的類圓形或分葉狀腫塊,呈等密度,密度不均勻,多合并低密度小囊變區(qū),病灶邊緣和內(nèi)部常見斑片樣或結(jié)節(jié)狀鈣化,。SEGA瘤體相對較大,增強(qiáng)后可見明顯強(qiáng)化。結(jié)節(jié)性硬化患者多合并室管膜下結(jié)節(jié)及皮層和(或)皮層下結(jié)節(jié),。室管膜下結(jié)節(jié)在CT上表現(xiàn)為側(cè)腦室壁室管膜下散在凸向側(cè)腦室的結(jié)節(jié)影,呈等或稍低密度,可見鈣化或僅表現(xiàn)為鈣化,。皮質(zhì)及皮層下結(jié)節(jié)CT上較難發(fā)現(xiàn)。

SEGA is usually a well-defined circular or lobulated mass with uniform density and uneven density, mostly with low-density cystic degeneration, and patchy or nodular calcification is common at the edge and inside of the lesion. The SEGA tumor was relatively large, and the enhancement was obvious after enhancement. Patients with tuberous sclerosis were more likely to have subependymal nodules and cortical and/or subcortical nodules. Subependymal nodules on CT showed scattered nodules in the lateral ventricles, with equal or slightly lower density, calcification or calcification. Cortical and subcortical nodules are difficult to detect on CT.

MRI:腫瘤在T1WI上呈等或稍低信號,T2WI上呈等或稍高信號,多合并小囊變,DWI呈等信號,增強(qiáng)掃描病灶呈不均勻明顯強(qiáng)化,。室管膜下結(jié)節(jié)在T1W1上呈等或高信號,在T2W1上呈等或低信號,DWI呈等信號,增強(qiáng)掃描病灶無明顯強(qiáng)化,。皮層和皮層下結(jié)節(jié)及類錯構(gòu)瘤樣腦白質(zhì)異常在MRI上呈T1WI等或稍低信號、T2WI等或稍高信號,增強(qiáng)掃描多無明顯強(qiáng)化,。SWI序列對鈣化灶敏感,、檢出率高,可彌補(bǔ)常規(guī)序列的不足。

The tumor showed equal or slightly lower signal on T1WI, equal or slightly higher signal on T2WI, more complicated with cystic degeneration, equal signal on DWI, and uneven and obvious enhancement on enhanced scan lesions. Subependymal nodules showed equal or high signal on T1W1, equal or low signal on T2W1, and equal signal on DWI, with no obvious enhancement on enhanced scan. Cortical and subcortical nodules and hamartoma-like white matter abnormalities showed T1WI equal or slightly lower signal and T2WI equal or slightly higher signal on MRI, with no obvious enhancement on enhanced scan. SWI sequence is sensitive to calcification and has high detection rate, which can make up for the deficiency of conventional sequence.

SEGA主要與好發(fā)于腦室系統(tǒng)的腫瘤相鑒別,如中樞神經(jīng)細(xì)胞瘤,、脈絡(luò)叢乳頭狀瘤,、室管膜下瘤、室管膜瘤等,。

SEGA is mainly differentiated from the tumors that tend to occur in the ventricular system, such as central nervous cell tumor, choroid plexus papilloma, supraependymoma, ependymoma, etc.

中樞神經(jīng)細(xì)胞瘤多見于20~40歲,多位于側(cè)腦室前2/3,、孟氏孔區(qū),常以寬基底附著于透明隔,體積較大,并沿透明隔向一側(cè)或雙側(cè)腦室內(nèi)生長,可見“蜂窩狀”或“絲瓜瓤狀”囊變區(qū)及具有特征性的瘤體內(nèi)血管流空現(xiàn)象,增強(qiáng)掃描強(qiáng)化不明顯或輕中度強(qiáng)化。

Central nervous cell tumor found in 20 ~ 40 years old, more than two-thirds, monro area is located in the lateral ventricle ago, often with wide base attached to the septum pellucidum, volume is larger, and the transparent across the brain to grow, to one side or both sides visible 'honeycomb' or 'vegetable sponge shape' are the areas of sac and has the characteristic of the blood flow within the tumors had empty phenomenon, strengthen the scan is not obvious or mild-to-moderate reinforcement.

脈絡(luò)叢乳頭狀瘤常見于10歲以下兒童,  常見部位為側(cè)腦室三角區(qū),少數(shù)成人可發(fā)生在第四腦室,呈分葉狀或菜花狀,增強(qiáng)掃描呈均勻明顯強(qiáng)化,少數(shù)不均勻強(qiáng)化,常因分泌過多的腦脊液,引起交通性腦積水,。 

Choroid plexus papilloma is common in children below 10 years old, common place is lateral ventricle trigonomery area, a few adult can happen in the fourth ventricle, show cent leaf shape or cauliflower shape, strengthen scan to show even and apparent aggrandizement, a few are not even aggrandizement, often because secreting excessive cerebrospinal fluid, cause traffic sex hydrocephalus.

少突膠質(zhì)細(xì)胞瘤也可發(fā)生于孟氏孔,多見于10~30歲,瘤體較大,可見帶狀或較大不規(guī)則狀鈣化,。

Oligodendroglioma can also occur in montesquires foramen, more often in 10 to 30 years of age, the tumor is large, visible zonal or large irregular calcification.

室管膜瘤40%發(fā)生于幕上,以側(cè)腦室三角區(qū)多見,好發(fā)年齡為30~50歲之間,囊變常見,沿腦室塑形生長,常浸潤?quán)徑X實(shí)質(zhì),增強(qiáng)掃描明顯不均勻強(qiáng)化。

Ependymoma occurs in the supratentorium in 40% of patients, and is more common in the trigonal area of the lateral ventricle. It is prone to occur between 30 and 50 years old. Cystic degeneration is common and grows along the ventricle, often infiltrating into the adjacent brain parenchyma.