脉络丛肿瘤( choroid plexus tumors)是起源于脉络丛上皮细胞的罕见脑肿瘤,占所有脑肿瘤的0.3%-06%,儿童脑肿瘤的1%-4%。肿瘤好发部位依次为侧脑室、四脑室和三脑室,极少数可发生于在脑室系统外，如脑实质和桥小脑角区。根据2016WHO分级,脉络丛肿瘤分为良性的脉络丛乳头状瘤( choroid plexus papilloma,CPP)(WHOI级)、介于良恶性之间的非典型脉络丛乳头状瘤atypical choroid plexus papilloma, ACPP)( WHO I级)和恶性的脉络丛癌( choroid plexus carcinoma,CPC)(WHOⅢ级)
Choroid plexus tumors are rare brain tumors that originate from the epithelial cells of the choroid plexus, accounting for 0.3% to 06% of all brain tumors and 1% to 4% of brain tumors in children. The most common sites of tumor are lateral ventricle, fourth ventricle and third ventricle, and very few can occur outside the ventricular system, such as parenchyma and cerebellopontine Angle. According to the 2016 WHO classification, choroid plexus tumors can be divided into benign choroid plexus papilloma (choroid and breadth papilloma, CPP) grade (WHOI), between benign and malignant atypical choroid plexus papilloma atypical choroid and breadth papilloma, ACPP) (WHO grade I) and malignant choroid plexus carcinoma (choroid and breadth carcinoma, CPC) (WHO Ⅲ level)
目前,脉络丛肿瘤的确切病因及发病机制尚不清楚,其肿瘤发生涉及多个基因突变、染色体失衡和信号通路异常。某些遗传缺陷综合征如Li-fraumeni综合征和 Von Hippel- Lindau综合征与脉络丛肿瘤发生也有一定关系。
At present, the exact etiology and pathogenesis of choroid plexus neoplasms are not clear. Some genetic defect syndromes such as li-fraumeni syndrome and Von Hippel- Lindau syndrome are also associated with choroid plexus neoplasms.
脉络丛肿瘤好发于1岁以下婴儿,占该年龄段脑肿瘤的10%~20%。国外报道脉络丛乳头状瘤年发病率约为3/1000万,高于脉络丛癌,两者发病率比例为5:1,男女发病比例为1.2:1。脉络丛癌主要见于18岁以下儿童,性别与发病率无明显相关。非典型脉络丛乳头状瘤极其罕见,其确切发病率、性别比例和年龄分布特点有待明确。
Choroid plexus tumors tend to occur in infants under 1 year of age, accounting for 10% to 20% of brain tumors in this age group. The annual incidence of choroid plexus papilloma is about 3/10 million, higher than that of choroid plexus cancer. Choroid plexus carcinoma is most common in children under 18 years of age. Atypical choroid plexus papilloma is extremely rare, and its exact incidence, sex ratio and age distribution need to be clarified.
脉络丛肿瘤的临床表现差异很大,与病变性质、发生部位和损害严重程度密切相关。脑室内肿瘤导致的临床表现常较重,患者主要表现为脑脊液循环障碍相关的症状和体征,如头痛、呕吐、视物模糊和压力性脑脊液鼻漏等,严重者可出现巨颅征、癲痫发作和脑疝。经脑脊液向颅外播散转移是脉络丛肿瘤的另一重要特征。大多数脉络丛癌转移至脊髓,极少数者可转移至腹腔、肺或胫骨。患者可出现脊髓相应节段或脏器损害的症状体征。脉络丛肿瘤的病理表现与其类型有关。脉络丛乳头状瘤属于良性肿瘤,表现为附着于脑室壁,与脑实质分界清楚的菜花样肿块。镜下可见由单层或假复层柱状上皮细胞包绕纤维血管轴心形成的典型乳头状结构。细胞核异型性不明显,无或少见核分裂象。非典型脉络丛乳头状瘤属于交界性肿瘤,肿瘤细胞具有较强的有丝分裂活动,局部区域细胞密度增高,核分裂象、核异型性和小灶状坏死常见。脉络丛癌属于恶性肿瘤,呈浸润性生长,出血及坏死多见,低分化肿瘤常失去典型乳头状结构。镜下可见肿瘤细胞有丝分裂活跃, 细胞密度增高,核异型性明显,局部可见瘤巨细胞和乳头状结构坏死。
The clinical manifestations of choroid plexus tumors vary greatly, which is closely related to the nature, location and severity of lesion. The clinical manifestations caused by intraventricular tumors are often severe, and the patients are mainly manifested as symptoms and signs related to cerebrospinal fluid circulation disorders, such as headache, vomiting, blurred vision and pressure cerebrospinal fluid rhinorrhea, etc. In severe cases, giant cranial signs, seizures and cerebral herniation may occur. Transcranial dissemination and metastasis via cerebrospinal fluid is another important characteristic of choroid plexus tumors. Most choroid plexus cancers metastasize to the spinal cord, and a few may metastasize to the abdominal cavity, lung, or tibia. Patients may show signs and symptoms of damage to the corresponding segments of the spinal cord or organs. The pathologic manifestations of choroid plexus tumors are related to their types. Choroid plexus papilloma is a benign tumor, which is characterized by a cauliflower mass attached to the ventricular wall and clearly demarcated from the brain parenchyma. Microscopically, a typical papillary structure is seen with single or pseudostratified columnar epithelial cells surrounding the fibrous vascular axis. Nuclear atypia is not obvious, no or rare mitosis. Atypical choroid plexus papilloma is a borderline tumor with strong mitotic activity, increased cell density in local areas, and common mitosis, nuclear atypia and focal necrosis. Choroid plexus carcinoma is a malignant tumor with infiltrating growth, hemorrhage and necrosis. Microscopically, the tumor cells showed active mitosis, increased cell density, marked nuclear atypia, and local necrosis of giant tumor cells and papillary structures.
脉络丛肿瘤的发病机制尚不清楚,其生物学过程与多个基因突变和信号通路有关。抑癌基因TP-53种系突变、转录因子TWIST-1过表达、信号通路(TRAIL、PDGFR和Notch-3)调控异常和染色体失衡共同促进了脉络丛肿瘤发生、肿瘤微环境形成和播散转移。
The pathogenesis of choroid plexus neoplasms is unknown, and its biological process is related to multiple gene mutations and signaling pathways. Mutations of tumor suppressor gene tp-53, overexpression of transcription factor twist-1, abnormal regulation of signaling pathways (TRAIL, PDGFR and Notch 3) and chromosomal imbalance jointly promoted the occurrence of choroid plexus tumors, formation of tumor microenvironment, and spread and metastasis.
脉络丛乳头状瘤
CT:肿瘤表现为分叶状或菜花状的等密度或稍高密度影,坏死、囊变及出血少见。肿瘤与周围组织分界清楚。瘤内钙化是脉络丛乳头状瘤较为特征的表现,多呈点状、斑片状或沙砾状高密度影。增强检查肿瘤表现为中度至明显均匀强化,有时可见扩张的脉络丛动脉穿入肿瘤实质。脑室系统呈不同程度扩张。
The tumor showed lobulated or cauliflower shaped shadows of equal or slightly higher density. Necrosis, cystic degeneration and hemorrhage were rare. The tumor is clearly demarcated from the surrounding tissue. Intratumoral calcification is the characteristic manifestation of choroid plexus papilloma. On enhanced examination, the tumor showed moderate to significant uniform enhancement, sometimes with dilated choroid plexus arteries penetrating the tumor parenchyma. The ventricular system expanded in different degrees.
MRI:显示钙化灶的敏感性不如CT,但可以更好明确肿瘤与周围组织的关系。脉络丛乳头状瘤多呈等长T1和等长T2均匀信号,T2WI序列上脑脊液与瘤体的信号对比可清晰勾画出瘤体轮廓,显示脑室受压程度和范围。肿瘤占位征象轻,瘤周水肿少见,部分较大者可因压迫周围脑室壁和脑实质在T2-FLAIR上出现高信号水肿带。肿瘤强化明显,细小颗粒状或桑葚样强化是脉络丛乳头状瘤的典型表现.
Calcification is less sensitive than CT, but it can better define the relationship between the tumor and the surrounding tissue. Choroid plexus papilloma mostly presents uniform signals of equal length T1 and equal length T2. The contrast of signals between cerebrospinal fluid and tumor on T2WI sequence can clearly outline the outline of tumor, indicating the degree and range of ventricular compression. The signs of tumor mass were mild and peritubercular edema was rare. In some larger cases, hypersignal edema zone on t2-flair could occur due to compression on the surrounding ventricular wall and brain parenchyma. Tumor enhancement was obvious, and fine granular or mulberrylike enhancement was the typical manifestation of choroid plexus papilloma.
非典型脉络丛乳头状瘤
CT:非典型脉络丛乳头状瘤常较脉络丛乳头状瘤大,表现为菜花状或不规则状的稍高密度肿块。肿瘤边界不清,可侵犯周围脑实质,瘤内可见混杂密度的囊变坏死区及点片状钙化灶。非典型脉络丛乳头状瘤的囊性成分常位于肿瘤一侧,对于本病的鉴别诊断有一定价值。肿瘤呈明显不均匀强化。病变梗阻部位以上脑室因脑积水呈不同程度扩大。
Atypical choroid plexus papillomas are often larger than choroid plexus papillomas, presenting as cauliflower or irregular mass with a slightly higher density. The boundary of the tumor is not clear, which may invade the surrounding brain parenchyma. The cystic component of atypical choroid plexus papilloma is usually located on one side of the tumor. The tumor showed obvious uneven enhancement. The ventricles above the site of lesion obstruction were enlarged due to hydrocephalus.
MRI:非典型脉络丛乳头状瘤表现为以长T1长T2为主的囊实性肿块。瘤内坏死、囊变及钙化较脉络丛乳头状瘤多见。肿瘤边界不清,侵犯压迫周围脑实质,T2-FLAIR可见高信号水肿带。部分肿瘤与周围脑组织间可见囊性长T1长T2信号,即“囊泡征”,可能是肿瘤阻碍脑脊液回流使脑脊液瘀滞于肿瘤与脑组织之间所致。增强检查病变呈明显不均匀强化.
Atypical choroid plexus papilloma presents as a solid cystic mass with long T1 and long T2. Intratumoral necrosis, cystic degeneration and calcification are more common than choroid plexus papilloma. The tumor was poorly circumscribed and intruded into the surrounding cerebral parenchyma with t2-flair hypersignal edema. Cystic long T1 and long T2 signals can be seen between some tumors and the surrounding brain tissue, which is known as 'vesicle syndrome'. It may be caused by the tumor obstructing cerebrospinal fluid reflux and causing cerebrospinal fluid stasis between the tumor and brain tissue. The enhancement examination showed obvious uneven enhancement.
脉络丛癌
CT:脉络丛癌体积较大,表现为分叶或不规则状混杂密度肿块。肿瘤强化及占位效应明显,边界模糊,周围脑室壁和脑实质受侵。
Choroid plexus carcinoma is large, presenting as lobulated or irregular mass with mixed density. Tumor enhancement and occupying effect were obvious, the boundary was blurred, the peripheral ventricle wall and brain parenchyma were invaded.
MRI:常规序列表现为长T1和稍长T2混杂信号影,肿瘤边界模糊,累及周围脑室壁并向脑实质浸润。T2-FLAIR上可见瘤周片状高信号水肿带。增强检查肿瘤呈明显不均匀强化。
Conventional sequences showed mixed signal shadows of long T1 and slightly longer T2, blurred tumor boundaries, involvement of the surrounding ventricular wall and infiltration into the brain parenchyma. Perituberous high signal edema bands are seen on t2-flair. Enhancement examination showed uneven enhancement of the tumor.
脑室内脉络丛肿瘤应与其他脑室内肿瘤鉴别;脉络丛肿瘤伴瘤内钙化应与少突胶质细胞瘤鉴别;脑室外如桥小脑角区脉络丛肿瘤应与听神经瘤、脑膜瘤和三叉神经瘤等鉴别,桥小脑角池改变是脉络丛肿瘤和其他桥小脑角区肿瘤鉴别的重要征象,脉络丛肿瘤位于脑内,桥小脑角池大多正常,而脑外肿瘤常伴局部扩张。
Intraventricular choroid plexus tumor should be distinguished from other intraventricular tumors. Choroid plexus tumor with intratumoral calcification should be distinguished from oligodendroglioma. Choroid plexus tumors in the cerebellopontine Angle region should be differentiated from acoustic neuromas, meningiomas and trigeminal neuromas, etc. Changes in the cerebellopontine Angle cifice are an important sign of choroid plexus tumors and other tumors in the cerebellopontine Angle region.
脑室内脑膜瘤为实性肿瘤,好发人群以中年女性多见,脑积水症状轻。而脉络丛肿瘤多见于儿童,脑室常因肿瘤梗阻致不同程度扩大;室管膜瘤呈实质性生长,囊变较多,常伴室管膜下浸润。而脉络丛肿瘤多局限于脑室内,少数肿瘤可经脑脊液播散形成远处病灶。
Ventricle meningioma is solid sex tumour, good hair crowd sees with middleaged female more, hydrocephalus symptom is light. Choroid plexus tumors are more common in children, and ventricles are often enlarged due to tumor obstruction. Ependymomas show substantial growth, more cystic changes, often accompanied by subependymal infiltration. However, choroid plexus tumors are mostly confined to the ventricle, and a few tumors can spread through CSF and form distant lesions.
少突胶质细胞瘤好发于成人,钙化较脉络丛肿瘤明显,其钙化特征呈局限点片状、条带状或不规则团块状,而脉络丛肿瘤多为点状或沙砾状钙化。
Oligodendrogliomas tend to occur in adults, and calcification is more obvious than choroid plexus tumors. The calcification features of oligodendrogliomas are localized patchy, banded, or irregular lumps, while choroid plexus tumors are mostly point or gravel calcification.
听神经瘤多有囊变,伴同侧听神经增粗和一定程度内听道扩大,而脉络丛肿瘤一般无内听道扩大表现。
Most acoustic neuromas have cystic changes, accompanied by ipsilateral auditory nerve enlargement and enlargement of the internal auditory canal to a certain extent, while choroid plexus tumors generally have no enlargement of the internal auditory canal.
桥小脑角区脑膜瘤与岩骨间夹角常为钝角,且以宽基底相连,可见典型“脑膜尾征”。
The Angle between the cerebellopontine Angle meningioma and the petrosal bone is usually obtuse and connected with a broad base.
三叉神经瘤常位于内听道前方颞骨岩部，呈跨后颅窝和中颅窝生长。
Trigeminal neuromas are usually located in the anterior temporal bone rock of the internal auditory canal.
