胶质母细胞瘤( glioblastoma)又称多形性胶质母细胞瘤( glioblastoma multiforme,GBM),是星形细胞肿瘤中恶性程度最高的类型,属WHOⅣ级,占神经上皮组织肿瘤的23%。可发生于任何年龄阶段,以45-65岁高发,30岁以下者少见,男性明显高于女性。病变好发部位依次为额颞叶、顶叶和枕叶,小脑和基底节区较为少见,也可以同时累及多个脑叶。
Glioblastoma (glioblastoma) is also called polymorphism glioblastoma (glioblastoma multiforme, GBM), is the highest type of astrocytes in the tumor malignant degree, belong to the WHO Ⅳ level, accounting for 23% of the epithelial tissue nerve tumors. It can occur at any age, with the highest incidence between 45 and 65 years old, rarely seen in people under 30 years old, and significantly higher in men than women. The most common lesion sites are frontotemporal lobe, parietal lobe and occipital lobe, and cerebellar and basal ganglia areas are rare, which can also involve multiple cerebral lobes at the same time.
按照版WHO分类,根据肿瘤细胞IDH基因状态,胶质母细胞瘤被分为“胶质母细胞瘤,IDH野生型”“胶质母细胞瘤,IDH突变型”和“胶质母细胞瘤,非特指”。其中“胶质母细胞瘤,IDH野生型”又称为“原发性胶质母细胞瘤”,约占胶质母细胞瘤的90%以上,缺乏明确低级别胶质瘤的演变过程,发病年龄常较大(平均年龄62岁),常伴有TERT启动子、 EGFR基因改变和染色体10p、10q异常,预后较差。“胶质母细胞瘤,IDH突变型”常由低级别胶质瘤转化而来、又称为“继发性胶质母细胞瘤”,约占10%,患者发病年龄较轻(平均年龄44岁),由于仍保持低级别弥漫性胶质瘤的基因特征,预后较好。在临床实践中应明确区分这两种类型,只有对那些没有经过基因检测的病例才可以诊断为“胶质母细胞瘤,非特指”。如果患者年龄小于55岁,免疫组化检测IDH1 R132H阴性者必须行分子测序以明确是否存在IDH1或IDH2突变,分子测序阴性者才可以诊断为“胶质母细胞瘤,IDH野生型”,而对于55岁以上的患者,如果免疫组化IDH1 R132H阴性,则无需进一步分子检测即可诊断。大多数胶质母细胞瘤(>50%)临床病程短(通常<3个月),主要见于中老年人(平均年龄62岁)。在全部胶质母细胞瘤中,继发性胶质母细胞瘤发生率10%,是由星形细胞瘤恶性变缓慢发展而来,病程长,由不足1年至以上。典型表现见于年轻人(平均年龄44岁)。常见颅内压增高的症状和体征(如头痛、恶心>
According to WHO classification in edition, glioblastoma is classified into 'glioblastoma,IDH wild type', 'glioblastoma,IDH mutant type' and 'glioblastoma, non-specific' according to the IDH gene status of tumor cells. Among them, 'glioblastoma,IDH wild-type' is also known as 'primary glioblastoma', accounting for more than 90% of glioblastoma. The evolution process of low-grade glioblastoma is not clear, and the onset age is often older (average age is 62 years old), accompanied by TERT promoter, EGFR gene changes and chromosome 10p and 10q abnormalities, with poor prognosis. 'Glioblastoma,IDH mutant' is often transformed from low-grade glioma, also known as 'secondary glioblastoma', accounting for about 10%. The onset age of the patients is relatively young (the average age is 44 years old), and the prognosis is good because the genetic characteristics of low-grade diffuse glioma are still maintained. These two types should be clearly distinguished in clinical practice, and only those cases without genetic testing can be diagnosed as 'glioblastoma, non-specific'. If patients younger than 55 years of age, and immunohistochemical testing IDH1 R132H negatie line must be molecular sequence in order to make clear whether IDH1 or IDH2 mutations, molecular sequencing negatie can be diagnosed as 'wild type' glioblastoma, IDH, and for patients over the age of 55, if immunohistochemical IDH1 R132H negative, without further molecular detection diagnosis. Most glioblastomas (>50%) have a short clinical course (usually <3 months)="" and="" are="" predominantly="" seen="" in="" the="" elderly="" (mean="" age="" 62="" years).="" among="" all="" glioblastomas,="" secondary="" glioblastomas="" have="" an="" incidence="" rate="" of="" 10%,="" which="" is="" caused="" by="" the="" slow="" development="" of="" astrocytoma="" malignant="" transformation,="" with="" a="" long="" course="" of="" disease="" ranging="" from="" less="" than="" 1="" year="" to="" more="" than="" 10="" years.="" it="" is="" typically="" seen="" in="" young="" people="" (average="" age="" 44).="" common="" signs="" and="" symptoms="" of="" increased="" intracranial="" pressure="" (e.g.,="" headache,="" nausea/vomiting,="" and="" associated="" papilloma).="" a="" third="" of="" the="" patients="" had="" seizures.="" sometimes="" headaches,="" personality="" changes="" and="" other="" non-specific="" neurological="" symptoms="" can="" also="">
胶质母细胞瘤的环形强化具有不同程度的厚壁,内壁(肿瘤活性部分与坏死部分的交界处)很粗糙,环形肿瘤实质部分在CT平扫时常表现为稍高密度,MR质子图和T2加权图呈相对的低信号,这种改变的精确机制尚不清楚,但可能的原因包括胶质细胞组织密度、血液、结缔组织增高或增多,以及多形性胶质母细胞瘤的血管增生特点。Dean强调,胶质母细胞瘤与恶性星形细胞瘤区别的MR特点之一是含铁血黄素或以前有出血的其他证据。必须强调的是,常规MR检查,即使有MR增强扫描,也仅仅能够勾画肿瘤的大体边界,恶性胶质细胞的肿瘤性浸润常常超出任何MR所发现的异常的范围。星形细胞肿瘤的信号强度变化无特异性而部位和形态常能够提示正确的诊断。穿过胼胝体强烈提示胶质瘤母细胞瘤可能性大,尽管这种情况也可见于原发性淋巴瘤。总之,CT和MR的典型表现是环性强化伴中央坏死。粗糙不规则的壁环绕中央一个或多个空腔,这些空腔可能是出血的证据。病变周围常可见到血管性水肿,有时在肿瘤占位效应中起重要作用。
Glioblastoma circular reinforced with different degree of thick wall and inner wall of active parts with necrosis (tumor border) is very rough, substantial part circular tumor in CT scan are often characterized by a high density, MR proton figure and T2 weighted graph was relatively low signal, the precise mechanisms of this change is not yet clear, but the possible reasons include increased density of glial cells, blood, connective tissue or increased, and vascular proliferation characteristics of pleomorphic glioblastoma. Dean emphasized that one of the MR characteristics that distinguishes glioblastomas from malignant astrocytomas is hemosiderin or other evidence of prior bleeding. It must be emphasized that routine MR examinations, even with enhanced MR scans, can only outline the general boundaries of the tumor, and the neoplastic infiltration of malignant glial cells often exceeds the scope of any abnormalities found by MR. The signal strength of astrocytoma is not specific, but the location and morphology can often suggest correct diagnosis. Crossing the corpus callosum strongly suggests glioma blastoma, although this condition is also seen in primary lymphoma. In summary, the CT and MR findings are typically cyclic enhancement with central necrosis. Rough, irregular walls surround one or more central cavities that may be evidence of bleeding. Vascular edema is often seen around the lesion and sometimes plays an important role in the tumor mass effect.
CT平扫肿瘤内多呈高、等、低混杂密度,高密度与出血相关,等密度区为肿瘤实质,中央低密度区常为坏死所致,钙化罕见,瘤周水肿较明显。增强呈显著不规则“花环样”强化。
In plain CT scan, the tumor showed high, equal and low confounding density, and high density was correlated with hemorrhage. The equal density area was the tumor parenchyma, while the central low density area was often caused by necrosis, calcification was rare, and peritumor edema was obvious. The enhancement showed a significantly irregular 'garlands like' enhancement.
MRI肿瘤通常较大,呈不规则形,信号不均匀,肿瘤实质呈等T稍长T2信号,中心坏死区呈长T1长T2信号,肿瘤内血管丰富,出血常见,可呈短T1、长T2信号,周围水肿区呈长T长T2信号,增强扫描呈显著的“花环样”强化,多数胶质母细胞瘤可沿白质束向周围扩散, 形成卫星病灶,可与中心病灶相连,也可不相连。肿瘤通过胼胝体、前联合及后联合扩展至对侧大脑半球,呈蝴蝶样形状为其典型表现。沿内囊和外囊扩展也很常见,也可沿蛛网膜下腔脑脊液播散种植。
MRI tumor is usually large, irregular shape, the signal is not uniform, tumor essence is a bit long T2 signals, such as T center necrosis area has long T1 long T2 signal, rich blood vessels within the tumor, hemorrhage in common, but a short T1 and long T2 signals, peripheral edema area has a long T2 signal, enhancement of the scan 'wreath' strengthening, most glioblastoma can spread along the beam into the surrounding white matter, form, satellite lesions can be connected to the center of lesions, also is not connected. Neoplasms spread to the contralateral cerebral hemispheres through the use of hydrazine callose, anterior and posterior combinations, and typically appear in the shape of butterflies. Expansion along the inner and outer sacs is also common and can be disseminated along the subarachnoid CSF.
MR灌注成像rCBV最大值升高;MRS上Cho峰明显升高,NAA峰明显降低,肿瘤周围水肿区Cho峰升高,说明肿瘤周围水肿区有肿瘤细胞浸润;SWI肿瘤内磁敏感信号强度( intratumoral susceptibility signal intensity)增加。
The maximum value of rCBV in MR perfusion imaging increased. Cho peak on MRS was significantly increased,NAA peak was significantly decreased, and Cho peak was increased in the peri-tumor edema area, indicating tumor cell infiltration in the peri-tumor edema area. SWI tumour magnetic sensitive signal intensity (intratumoral susceptibility signal intensity).
鉴别诊断
转移瘤绝大部分具有原发病灶,好发于灰白质交界处,病灶周围水肿比胶质母细胞瘤明显,增强扫描呈均匀结节样或环状强化。单发转移瘤有时与胶质母细胞瘤较难鉴别,需要借助MRS等其他功能序列进行鉴别。
Most metastatic tumors have primary lesions, which tend to occur at the junction of gray and white matter. Edema around the lesions is more obvious than that of glioblastoma, and the enhanced scan shows uniform nodular or annular enhancement. The single metastatic tumor is sometimes difficult to distinguish from glioblastoma, so it needs to be identified by MRS and other functional sequences.
颅内原发淋巴瘤属小圆细胞类肿瘤,好发于免疫力低下的中老年男性,常累及 深部灰质核团或脑表面,影像学表现为边界清楚的占位性病变,周边水肿范围常较胶质母细胞瘤小,出血、囊变少见,增强后明显均匀强化,可见“尖角征”或“握拳征”,而胶质母细胞瘤多有不同程度坏死,增强扫描不均匀强化、环状强化,瘤周水肿程度轻至重度不等
Intracranial primary lymphoma is a small round cell tumor, occurs in older men with low immunity, often involving deep gray matter nuclei or brain surface, the imaging findings of boundary clear space-occupying lesions, peripheral edema often much broader than those of glioblastoma is small, hemorrhage, capsule, rare, obvious homogeneous enhancement, visible 'Angle' or 'fist', while glioblastoma necrosis to different extent, uneven enhancement scanning strengthening, annular strengthening, tumor weeks edema degree of light to heavy
发生于大脑表面或大脑镰旁的胶质母细胞瘤还需要与脑膜瘤鉴别。脑膜瘤起源于蛛网膜颗粒细胞,密度或信号均匀,增强扫描明显强化,相邻颅骨可有受压改变,在压迫静脉回流时有水肿形成。若胶质母细胞瘤局部与硬脑膜或大脑镰关系密切、且表现缺乏特异性时,易与脑膜瘤相混淆,此时肿瘤脑内外的定位有很重要的鉴别诊断意义。
Glioblastoma, which occurs on the surface of the brain or near the falx, needs to be identified from meningiomas. Meningioma originated from arachnoid granulosa cells, with uniform density or signal, and obvious enhancement on enhanced scan. There may be compression changes in adjacent skulls, and edema is formed when pressing venous refluxes. If glioblastoma is closely related to the dura or falx of the brain locally, and its manifestations lack specificity, it is easy to be confused with meningioma. At this time, the localization of tumor inside and outside the brain has very important significance in differential diagnosis.
发生于脑实质的室管膜瘤也需要与胶质母细胞瘤鉴别,常表现为T1WI稍低信号,T2WI呈高信号,坏死囊变常见,有时可有钙化,当出现钙化时,强烈提示室管膜瘤可能性大。
Ependymoma occurring in the brain parenchyma also need to be differentiated from glioblastoma, often presenting as low signal on T1WI, high signal on T2WI, common necrotic cystic degeneration, and sometimes calcification, which strongly suggests the possibility of ependymoma when calcification occurs.
尽管可以对肿瘤进行手术切除、放射治疗和应用化学药物治疗,但是胶质母细胞瘤患者的生存率仍然很低。瑞士和加拿大的一项回顾性研究显示,生存期超过1年者不到20%,患者存活超过3年不足3%。
Survival rates for glioblastoma patients remain low, despite surgical excision, radiation therapy and chemotherapy. A retrospective study in Switzerland and Canada showed that less than 20% of patients survived more than one year, and less than 3% survived more than three years.