Choroid plexus papilloma

Introduction to choroid plexus papilloma The choroid plexus is differentiated from the specific cerebral ventricle epithelium. Some authors believe that the ependymal cells of a certain ventricular wall are degenerated, and its main function is to secrete cerebrospinal fluid. Choroid plexus papilloma can occur in the choroid plexus epithelium or ventricular wall glial cells, which have the characteristics of secreting cerebrospinal fluid, generally slow growth, rarely malignant. It is a benign tumor that occurs in the choroid plexus epithelium. Found in the ventricular system and cerebral cerebral horns. The tumor is mostly substantial and has a clear boundary with the surrounding tissue. The tumor tissue is red, the surface is granular, there are fluff, and there may be calcification. Under the microscope, the choroid plexus papilloma resembles the normal structure of the choroid plexus. Due to the slow growth of the tumor, the course of disease is longer, and it can be cancerous over a long period of time. It can also be spread by the subarachnoid space, and it is located in the ventricle, and secrete more cerebrospinal fluid, which is easy to cause traffic hydrocephalus. basic knowledge The proportion of illness: 0.005% Susceptible people: no special people Mode of infection: non-infectious Complications: ataxia, subarachnoid hemorrhage

The cause of choroid plexus papilloma

Causes:

Virus factor (25%):

Animal studies have found that SV40 virus can induce choroid plexus papilloma, human papillomavirus E6, E7 oncogene is also related to tumorigenesis, but there is no evidence directly related to tumor incidence.

Pathogenesis:

The choroid plexus papillary tumor grows mostly along the ventricle, generally small in size, shaped like cauliflower, nodular growth, dark red, irregular papillary protrusion on the surface, clear boundary with the surrounding brain tissue, and small tumor surface It is also called mulberry-like shape. It is called mulberry-like shape. The cut surface is rough and the tissue is easy to fall off. The texture is brittle. The cystic change and hemorrhagic necrosis rarely occur, and fine calcified particles can also be seen.

Under light microscope, the tumor cells differentiate well, and the morphology is normal choroid plexus. It is a single layer of rectangular or columnar epithelial cells arranged neatly in the basal layer. It is often arranged in the pseudo-stratified arrangement in the axis of loose connective tissue. Around the heart, a small papillary structure is formed. The center of the mastoid is rich in blood vessels. The axis of the mastoid is often seen with spherical calcareous deposits, called calcified bodies. It is rare to see mitotic figures of tumor cells. The interstitial is composed of small blood vessels and connective tissue. This is the point of differentiation from papillary ependymoma. Some tumors have cilia and hairy bodies. Immunohistochemical staining revealed GFAP, S100, cytokeratin in choroid plexus papilloma. It is positive for transthyretin, and transthyretin is considered to be relatively specific to choroid plexus papilloma. In a few autopsy cases, choroid plexus papilloma can be found on the soft meninges, but such cases are often absent. Spread the symptoms.

Increased choroid plexus (20%):

The choroid plexus was proposed by Davis in 1924. It is mainly characterized by enlarged choroid plexus in the bilateral lateral ventricles, accompanied by congenital hydrocephalus, which is different from bilateral ventricular choroid plexus papilloma, although the choroid plexus excessively secretes cerebrospinal fluid. However, histology did not show tumor changes.

Electron microscopic observation showed that the tumor cells were monolayer-column, arranged in a mastoid shape, with obvious apical to basal directionality. The surface of the tumor cells was rich in vigorous microvilli, and the apical junction was used to connect the complexes - the occluded zonules and bridges. The granules, the lateral cell membranes are interdigitated, the basal surface is smooth, attached to the basement membrane, the cilia are mixed between the microvilli, the clustered matrix can be seen in the cytoplasm, occasionally the small roots of the transverse stripes, and the cytoplasmic electron density is different. Thus, there can be a mixture of light and dark cells, and a large number of mitochondria and abundant glycogen are visible. Glycogen and cilia are particularly prominent in infant choroid plexus papilloma, which is not characteristic in adult and old age, generally without cytoplasmic filaments, occasionally cytoplasmic filaments. Prominent, differentiated into ependymal cells, the glia filaments are prominent with the aging of the normal choroid plexus, which is also characteristic of senile choroid plexus papilloma, the nucleus is round or polygonal, located in the center of the cell, the center of the mastoid The vascular endothelial cells are fenestrated and have a filtering function, which is ultrastructural evidence of excessive tumor production of cerebrospinal fluid.

Malignant choroid plexus papilloma accounts for 10% to 20% of the total, invasive growth, localized necrosis, histologically visible tumor cell atypicality, tumor cells appear a large number of mitotic figures, although the tumor is malignant Histological manifestations, but most still maintain its papillary structure, electron microscopy in addition to retain some characteristics of benign choroid plexus papilloma, there may be a series of anaplastic changes, tumor cells are arranged in a sheet, Loss of papillary and directional alignment, intercellular connection dysplasia, few organelles, but a large number of polyribosomes, microvilli dysplasia, cilia is extremely rare, the proportion of nucleoplasm is increased, nuclear chromatin is evenly distributed in fine particles. The mitotic division is common, and about 10% of choroid plexus papilloma has malignant transformation, which can be called choroid plexus papillary carcinoma.

Choroid plexus papilloma prevention

Refer to the general tumor prevention methods, understand the risk factors of tumors, and develop appropriate prevention strategies to reduce the risk of cancer.

1. Avoid harmful substances (promoting factors) that can help us avoid or minimize exposure to harmful substances.

2. Improve the body's immunity against tumors can help improve and strengthen the body's immune system and cancer.

Choroid plexus papilloma complications Complications, ataxia, subarachnoid hemorrhage

Visual impairment, ataxia, forced head position, spontaneous subarachnoid hemorrhage, etc. may occur.

Symptoms of choroid plexus papilloma Common symptoms Edema, sleepiness, nausea and vomiting, irritability, hydrocephalus, nystagmus, tremor, apathy, coma, focal symptoms, increased intracranial pressure

Choroid plexus papilloma is mainly characterized by hydrocephalus caused by hydrocephalus. This is mainly due to excessive secretion of cerebrospinal fluid by the tumor, obstruction of cerebrospinal fluid circulation, or adhesion of subarachnoid space due to tumor hemorrhage. On average, about 1.5 years, the disease duration of children under 2 years old is about 2 months, and the age of 2 years and older can reach 6 months. There are two types of symptoms: increased intracranial pressure and localized nerve damage, except headache, nausea, vomiting and other symptoms. In addition, patients may have seizures (18%) in the early stage, and later may be irritability (33%), mental discomfort (33%) and blurred vision (18%), but focal symptoms are often not obvious, 25 % of patients may have apathy, or even change in consciousness, and there is an increase in acute intracranial pressure.

1. Increased hydrocephalus and intracranial pressure: Most patients have hydrocephalus, including the location of brain tumors directly obstructing cerebrospinal fluid circulation caused by obstructive hydrocephalus and cerebrospinal fluid production and absorption disorders caused by traffic In both cases of hydrocephalus, the clinically common increase in intracranial pressure in patients with choroid plexus has a direct relationship with the occurrence of hydrocephalus. Of course, the tumor occupying effect is also an important cause of increased intracranial pressure. Increased intracranial pressure in infants and young children is characterized by increased head and increased anterior tendon tension, mental apathy, lethargy or irritability. In older children and adults, it can manifest as headache, vomiting, and optic disc edema, and may even appear. Paroxysmal coma, severe hydrocephalus can reduce seizure function or direct tumor effects can lead to seizures.

2. Localized neurological damage: The manifestations of localized nervous system damage vary depending on the location of the tumor. Half of the tumors in the lateral ventricle have contralateral mild pyramidal tract signs; those located in the posterior third ventricle are both eyes. Difficulty in upper eye; in the posterior cranial fossa, it is characterized by unstable walking, nystagmus and dyskinesia. Individuals located in the lateral ventricle may present as head mass. Clinically, there may be spontaneous subarachnoid hemorrhage. The medical history, the tumor is mostly located in the ventricle, and some can be moved. Therefore, some patients show sudden increase or relief of headache, and a few have forced head position, which may be caused by sudden obstruction of the cerebrospinal fluid circulation pathway after the tumor moves.

Examination of choroid plexus papilloma

Cerebrospinal fluid examination: increased intracranial pressure with lumbar puncture combined with obstructive hydrocephalus, increased cerebrospinal fluid protein content is one of the characteristics of this disease, and some even appear yellow.

X-ray film

In some patients, the X-ray plain film showed an increase in intracranial pressure, a widening of the cranial suture, an abnormality of the craniofacial area, and a "silver line" sign in the skull. The indentation of the adult finger was increased, and the child was separated by the cranial suture, 15%. 20% can be seen pathological calcification, and the calcification of lateral ventricle tumor is more unilateral than that of normal choroid plexus.

2. Cerebral angiography

Cerebral angiography showed deeper tumor staining and showed thickening of the tumor supplying artery from the normal choroid plexus. The lateral ventricle tumor in the triangular region was often the lateral posterior choroidal artery, and the fourth intraventricular tumor was often the posterior cerebellum. The branch of the artery, while the third ventricle choroid plexus papilloma is the medial posterior choroidal artery.

3. CT examination

The tumor was significantly enlarged in the cerebral ventricle during CT scan, with high density shadow inside, enhanced scan showed uniform enhancement, clear and irregular margins, pathological calcification, and sometimes subarachnoid hemorrhage. The tumor was mostly unilateral, rarely For the bilateral side, the lateral ventricle is mostly in the triangle area, and the posterior cranial fossa is often accompanied by supratentorial hydrocephalus. Except for the choroid plexus mastoid tumor, the tumor is mostly confined to the ventricle, and there is no obvious midline structure shift. .

4. MRI examination

The MRI findings of the tumor were low in the T1-weighted image, lower than the brain parenchymal signal but higher than the cerebrospinal fluid signal; high signal in the T2-weighted image, clear boundary with the cerebrospinal fluid and irregular tumor contour, some visible focal hemorrhage, calcification With vascular emptying, the tumor has a significant contrast enhancement and hydrocephalus.

Diagnosis and diagnosis of choroid plexus papilloma

According to the clinical manifestations and auxiliary examination data, a clear diagnosis can generally be made. However, choroid plexus papilloma and choroidal carcinoma cannot be reliably distinguished by imaging examination alone.

Many tumors need to be differentiated from choroid plexus tumors. The villus hypertrophy is diffusely enlarged in the choroid plexus of the two lateral ventricles, and the histological morphology is normal. Patients often have high secretory hydrocephalus. The identification of choroid plexus and metastatic cancer is very important. Choroid plexus tumors co-express vimentin, keratin and s-100 eggs, which help to differentiate from other metastatic cancers. In addition, IEAl25 and Bm'EP4 are also helpful because they mark 95% of brain metastases, while choroid plexus papilloma and choroid plexus cancer are only 10% positive. Thyroid carrier protein is involved in the conversion of thyroxine and vitamin A and is a marker of normal and neoplastic choroid plexus epithelium. However, about 20% of choroid plexus papilloma is negative, while other brain tumors and metastatic cancers can be positive. It has recently been reported that normal choroid plexus, choroid plexus papilloma, and choroid plexus cancer are strongly positive for synaptophysin, but this finding has not been confirmed by others. One study showed that insulin-like growth factor II (IGFII) can be expressed in choroid plexus papilloma, but other brain tumors are negative. Since previous studies have shown that IGF11 can be expressed in astrocytomas, meningioma, and cancer, whether IGF lJ has a differential diagnosis remains to be confirmed. Carcinoembryonic antigen (CEA) positive indicates metastatic cancer, although occasionally choroid plexus cancer is also positive. Non-epithelial leafy tumors can also originate from the choroid plexus, including meningiomas.

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