Pediatric intracranial tumor
Introduction
Introduction to intracranial tumors in children Intracranial tumors are one of the more common tumors in children. Because children with intracranial tumors are more malignant and benign tumors are difficult to remove and difficult to remove, they often endanger children's lives. The incidence rate is the second highest among children under 15 years old. The age of intracranial tumors is mainly in two age groups. The first peak is within 10 years old, and the incidence rate is 2.2/100,000 to 2.5/100,000 per year. Slightly more than female (1.1:1). The second peak starts from 30 to 40 years old and reaches the peak at the age of 60. This stage is the best period for tumors. Children with intracranial tumors are different from adults, 40% to 60% occur under the curtain, and tumors mainly occur in embryonic residual tissues. There are relatively few gliomas. Adults often occur on the screen, with gliomas as the Lord. basic knowledge The proportion of sickness: 0.01% Susceptible people: children Mode of infection: non-infectious Complications: nystagmus brain stem tumor epilepsy cerebral palsy precocious puberty
Cause
Pediatric intracranial tumor etiology
(1) Causes of the disease
The exact cause has not been found.
(two) pathogenesis
Pathogenesis
At present, according to the characteristics of certain tumors, pathology and some basic experimental research, several theories are proposed.
(1) Genetics: In the field of neurosurgery, some tumors have obvious family tendencies, such as retinoblastoma, vascular reticuloma, multiple neurofibromas, etc., which are generally considered to be autosomal dominant. Hereditary tumors have a high penetrance rate.
(2) Virology: Experimental studies have shown that some viruses, including DNA viruses and RNA viruses, can induce brain tumors if inoculated into the brain of animals.
(3) physics and chemistry said: the physical factors identified in the tumor is likely to be radiation, there have been many reports of intracranial tumors caused by cranial radiotherapy, in chemical factors, polycyclic aromatic hydrocarbons and nitric acid compounds, such as Methylcholine, benzopyrene, methylnitrosourea, nitrosopiperidine, can induce brain tumors in some animal experiments.
(4) Immunosuppression theory: the application of organ transplant immunosuppressive drugs will increase the risk of intracranial or peripheral tumors.
(5) Embryonic residual theory: craniopharyngioma, epithelioid and dermoid cysts, teratoma, chordoma obviously occur in the embryonic tissue remaining in the brain, these residual tissues have the potential of proliferation and differentiation, under certain conditions Developed into a tumor.
2. Classification
There are many methods for classification of central nervous system intracranial tumors. The most representative ones are the following. See Table 1. The classification of Bailey and Cushing can reflect the source and malignancy of tumor tissue. It has long been used in neurosurgery in most parts of the world. The pathology department used, based on this, some new classification methods were derived, such as Kernohan's I-IV classification, Russell's glioma classification, and more influential is that Kernohan proposed to include gliomas, including astrocytes. Tumors, oligodendrogliomas, ependymoma, and neurogenic tumors are classified into grades I-IV according to their degree of differentiation. According to this classification, it seems that the development of tumors and the prognosis of patients can be easily judged, so they are clinicians. Welcome, used in domestic and international for many years, but this classification is also flawed, such as the same tumor in different parts, cell differentiation can be different, some mixed tumors can not be graded, and some tumors are not meaningful, on this basis, the World Health Organization A new taxonomy has been developed, which is characterized by a detailed classification, including various types of tumors that occur in the brain, and absorbs various classifications Features and advantages, both to reflect the tumor morphology, but also indicate the source of the tumor, and the use of change between this concept can be considered as the best classification.
Prevention
Pediatric intracranial tumor prevention
This disease has not been clearly defined as the cause of the disease, refer to the general method of prevention of cancer.
Understanding the risk factors of tumors, developing appropriate prevention strategies can reduce the risk of tumors, and there are two basic clues to prevent tumors. Even if tumors have begun to form in the body, they can help the body to improve resistance. These strategies are as follows:
1. Avoid harmful substances (promoting factors)
It is able to help us avoid or minimize exposure to harmful substances.
Some related factors of tumorigenesis are prevented before the onset, and many cancers can be prevented before they are formed. A report in the United States in 1988 compared the international malignant tumors in detail and proposed many external factors of known malignant tumors. In principle, it can be prevented, that is, about 80% of malignant tumors can be prevented by simple lifestyle changes, and traced back. In 1969, Dr. Higginson's research concluded that 90% of malignant tumors are caused by environmental factors," "Environmental factors", "lifestyle" refers to the air we breathe, the water we drink, the food we choose to make, the habits of activities, and social relationships.
2. Improve the body's immunity against tumors
Can help to strengthen and strengthen the body's immune system and cancer.
The focus of our current cancer prevention efforts should first focus on and improve those factors that are closely related to our lives, such as quitting smoking, eating properly, exercising regularly, and losing weight. Anyone who follows these simple and reasonable lifestyles can Reduce the chance of cancer.
The most important thing to improve the function of the immune system is: diet, exercise and control troubles. Healthy lifestyle choices can help us stay away from cancer. Maintaining good emotional state and proper physical exercise can keep the body's immune system at its best. Tumors and prevention of other diseases are equally beneficial. Other studies have shown that appropriate activities not only enhance the body's immune system, but also reduce the incidence of colon cancer by increasing the peristalsis of the human intestinal system. Here we mainly understand the diet in preventing tumorigenesis. Some questions.
Human epidemiology and animal studies have shown that vitamin A plays an important role in reducing the risk of cancer. Vitamin A supports normal mucosa and vision. It directly or indirectly participates in most of the body's tissue functions. Vitamin A is present in animal tissues. In the liver, whole eggs and whole milk, the plant is in the form of -carotene and carotenoids, which can be converted into vitamin A in the human body. Excessive intake of vitamin A can cause adverse reactions in the body and -carrot This is not the case with carotenoids, and the low vitamin A content in the blood increases the risk of malignant tumors. Studies have shown that those with low levels of vitamin A intake in the blood increase the likelihood of lung cancer, while those with low blood levels in smokers Levels of vitamin A ingestors have the potential to double lung cancer. Vitamin A and its mixture can help remove free radicals in the body (free radicals can cause damage to genetic material), and secondly stimulate the immune system and help differentiate cells in the body. Ordered tissue (while the tumor is characterized by disorder), some theories suggest that vitamin A can help early carcinogens Invasion mutated cells become reversed the occurrence of the normal growth of cells.
In addition, some studies suggest that supplementation with -carotene alone does not reduce the risk of cancer, but rather increases the incidence of lung cancer. However, when -carotene binds to vitamin C, E and other antitoxin substances, its protective effect. It is shown, because it can increase free radicals in the body when it is consumed by itself. In addition, there are interactions between different vitamins. Both human and mouse studies have shown that the use of -carotene can reduce 40% of vitamins in the body. At E-level, a safer strategy is to eat different foods to maintain a balanced vitamin to protect against cancer, as some protective factors have not been discovered so far.
Vitamin C, E is another anti-tumor substance that prevents the harm of carcinogens such as nitrosamines in food. Vitamin C protects sperm from genetic damage and reduces the risk of leukemia, kidney cancer and brain tumors in their offspring. Vitamin E can reduce the risk of skin cancer. Vitamin E has the same anti-tumor effect as vitamin C. It is a scavenger that protects against toxins and scavenges free radicals. The combination of vitamins A, C and E protects the body against toxins. Better than applying it alone.
At present, research on phytochemistry has attracted widespread attention. Phytochemistry is a chemical found in plants, including vitamins and other substances found in plants. Thousands of plant chemicals have been found, many of which have anticancer properties. The protective mechanism of these chemicals not only reduces the activity of carcinogens but also enhances the body's immunity against carcinogens. Most plants provide antioxidant activity that exceeds the protective effects of vitamins A, C, and E, such as a cup of cabbage. Contains 50mg of vitamin C and 13U of vitamin E, but its antioxidant activity is equivalent to the antioxidant activity of 800mg of vitamin C and 1100u of vitamin E. It can be inferred that the antioxidant effect in fruits and vegetables is far better than what we know. The effect of vitamins is strong, and no doubt natural plant products will help prevent cancer in the future.
Complication
Pediatric intracranial tumor complications Complications nystagmus brain stem tumor epilepsy cerebral palsy
Local symptoms vary depending on the location and size of the tumor. Cerebral hemisphere tumors near the central anterior and posterior gyrus may have weak or partial hemiplegia, affecting the language center may have motor or sensory aphasia, and the saddle area tumor may have optic nerve origin. Sexual atrophy and vision, visual field changes, tumors affect the pituitary - hypothalamus may have growth and development disorders, obesity or weight loss, polydipsia and body temperature regulation disorders, under-the-spot tumors have gait instability, nystagmus, muscle tone and paralysis Reflex decline, brain stem tumors have cranial nerve damage and contralateral pyramidal signs, pineal tumors have eyeball difficulty and precocious puberty, often with epilepsy, cerebral palsy and so on.
Symptom
Pediatric intracranial tumor symptoms common symptoms Tuen Mun beating recurrent headaches expression indifferent expression of increased intracranial pressure, irritability, lethargy, cranial suture, premature closure, disturbance of consciousness, compulsive head pulsation
Pediatric intracranial tumors occur in the midline and posterior fossa, so it is easy to block the cerebrospinal fluid circulation pathway early, and there are important structures such as increased intracranial pressure and pressure brainstem. The course of disease is often shorter than that of adults. At the same time, due to incomplete development of children's skull, generations The ability to pay is stronger than that of adults, so the symptoms of localized nervous system damage are relatively less than that of adults, mainly due to increased intracranial pressure. Common symptoms are as follows:
General symptoms
Increased intracranial pressure in children can be expressed as irritability and irritability, while some are indifferent or lethargic. If there is a disturbance of consciousness, slow pulse, slow breathing, high blood pressure indicates that it has entered the early stage of cerebral palsy, need to do emergency reduction of intracranial pressure, children The intracranial pressure compensatory ability is higher than that of adults, and the increase of intracranial pressure occurs later. Once decompensation, the condition deteriorates sharply, so early diagnosis is very important.
Vomiting
About 70% to 85% of children have vomiting, which is caused by increased intracranial pressure or posterior fossa tumor directly stimulating the medullary vomiting center. In some children (about 10% to 20%) vomiting is the only early symptom. Among them, infants and young children are more common, vomiting can be accompanied by headache or dizziness, vomiting is not all jetting, more common in the morning or after breakfast, often can eat immediately after vomiting, and then quickly vomiting, a small number of children can accompany Have abdominal pain, early misdiagnosis as a gastrointestinal disorder.
3. headache
70% to 75% of children have headaches, the on-screen tumor headache is mostly in the forehead, and the under-the-slice tumor is mostly in the occipital region, mainly due to increased intracranial pressure or brain tissue displacement, causing meningeal, vascular or cranial nerve tension traction. As a result, the headache may be intermittent or persistent, and gradually increase with the prolongation of the course of the disease, but when the visual loss is more obvious, the infant can not complain of headache, and can express both hands, scratching his head or bursting into tears. It should be taken seriously for children's headaches because there are few functional headaches in this age group.
4. Visual impairment
Vision loss can cause primary optic nerve atrophy due to direct compression of the visual pathway in the sellar region. It is more due to secondary optic atrophy caused by optic disc edema due to increased intracranial pressure. Optic disc edema depends on the location, nature and duration of the tumor. The posterior fossa tumor is larger and heavier in the hemisphere. The higher the malignant degree or the longer the course of the tumor, the more obvious the optic disc edema. Children's vision loss is easily ignored by the parents. Therefore, there are less than 40% of the chief complaints. In 10% of the children, the eyes were nearly blind or blind. In this group, 2,000 patients with optic disc edema accounted for 75%, the optic nerve atrophy was 8.4%, the visual field changed less, and the larger tumor in the sellar region. There may be bilateral sacral hemianopia; in the late stage of optic disc edema, there may be a reduction in visual field centripetality, but pediatric visual field examination often fails to cooperate.
5. Head enlargement
Head enlargement and broken pot sound (McCewen sign) positive, more common in infants and younger children, due to incomplete cranial suture healing or fibrous healing, increased intracranial pressure can cause cranial suture separation head circumference increased, percussion can be Smell and broken pot sound, this group of head enlargement accounted for 48.9%, infants within 1 year old can also see anterior sacral bulging and scalp venous engorgement, but not as serious as congenital hydrocephalus, the tumor is located in the cerebral hemisphere convex is still visible The skull is locally raised and the appearance is asymmetrical.
6. Neck resistance or forced head position
Pediatric intracranial tumors are more common in this manifestation. The third ventricle tumor can be in the knee chest position, and the posterior fossa tumor is skewed to the affected side to keep the cerebrospinal fluid circulating smoothly. It is a kind of protective reflection of the body. Resistance is more common in posterior fossa tumors, due to chronic cerebellar tonsillar sacral or tumor growth and compression of the upper cervical nerve root. For such patients to prevent the occurrence of occipital foramen magnum, early ventricular puncture drainage or Dehydration drugs reduce intracranial pressure.
7. Seizures
The incidence of epilepsy in children with brain tumors is lower than that of adults. The reasons are: there are more tumors under the eyes of children; and more common malignant tumors, more symptoms of brain tissue damage than irritation, this group of epilepsy authors accounted for 10%.
8. fever
The history of fever in the course of the disease is a characteristic manifestation of pediatric brain tumors. The incidence rate of this group is 4.1%, which is related to the more malignant brain tumors in children and the instability of body temperature regulation.
9. Double vision and strabismus in the eye
Mostly caused by increased intracranial pressure caused by nerve palsy, can occur at the same time, mostly bilateral.
Examine
Examination of intracranial tumors in children
Lumbar puncture examination should be classified as contraindication for children with optic disc edema, which can induce cerebral palsy. When the child is crying, the pressure measurement is often inaccurate. The "white blood cells" of cerebrospinal fluid in children with brain tumors can be increased, but it should be differentiated from the shed tumor cells. The protein is increased and the sugar and chloride are normal, which is different from the inflammatory response.
1. Skull X-ray film to understand whether there is increased intracranial pressure (cranial suture separation and finger pressure increase), and whether there are abnormal calcifications (more common in craniopharyngioma and oligodendroglioma).
2. Cerebral angiography tumors can be seen when there is a space-occupying effect; abnormal blood staining can be seen in tumors rich in blood supply.
3. Computerized tomography (CT) can not only accurately locate, but also understand tumor size, cystic solidity, calcification, blood supply and peritumoral edema.
4. Magnetic resonance imaging (MRI) has a sharper contrast and a better anatomical background, especially for the midline and posterior fossa tumors, but not as good as calcification and bone.
Diagnosis
Diagnosis and diagnosis of intracranial tumors in children
diagnosis
When children have recurrent episodes of headache and vomiting without obvious causes, the possibility of intracranial tumors should be considered. Do not relax the symptoms due to symptom relief. Careful neurological examination should be performed for children with suspected intracranial tumors. Discretionary brain X-ray, brain CT, MRI and other auxiliary examinations should be performed as appropriate.
Differential diagnosis
Children with poor expression ability and poor development of the nervous system or uncooperative physical examination, symptoms and signs can not be obvious, and many symptoms similar to other children's diseases, or after other diseases, it is easy to misdiagnosis, should be highly valued, Pediatric brain tumors are most easily misdiagnosed as the following diseases:
1. Meningitis or encephalitis due to fever in children with brain tumors accounted for 4.1%; cerebrospinal fluid can be inflammatory-like changes and combined with cerebellar tonsillar chin under the neck resistance, clinically misdiagnosed as tuberculous or suppurative meningitis.
2. Gastrointestinal disorders When the intracranial pressure is increased, the child has vomiting after repeated eating, and is easily misdiagnosed as gastroenteritis or pyloric obstruction and intestinal ascariasis.
3. Congenital hydrocephalus The brain enlargement of infantile brain tumors, high anterior tendon tension and scalp vein anger and hydrocephalus are similar, but the following characteristics are helpful for identification. The onset of hydrocephalus is earlier than intracranial tumors. More often, the head gradually increases after birth; obvious eyeballs fall; the optic disc is more edema; less vomiting symptoms.
4. Neurological headache Children with headache are mostly organic lesions, and should be further examined.
5. Diabetes insipidus is mostly a symptom of a tumor in the sellar region rather than a disease.
6. Ophthalmological diseases Brain tumor caused by optic disc edema and secondary optic atrophy can affect vision vision, easy to be misdiagnosed as optic discitis or optic neuritis, medical history and auxiliary examination can help identify.
7. There are about 10% of epileptic seizures in children with epilepsy. Only the exclusion of tumors and vascular lesions can make a diagnosis of primary epilepsy.
8. Cerebellar ataxia is a degenerative lesion of the cerebellum. Slow progression and no increase in intracranial pressure can be distinguished from posterior fossa tumors.
