Pilocytic Astrocytoma

A pilocytic astrocytoma is a mostly benign brain tumor in children and adolescents. Among other things, the cerebrum, diencephalon, spinal cord or optic nerve can be affected. After a full operation there are no more recurrences.

Pilocytic Astrocytoma

What is pilocytic astrocytoma?

Pilocytic astrocytoma is a benign brain tumor characterized by slow proliferation of supporting cells in the central nervous system called glial cells. It therefore also belongs to the gliomas. The tumors of the nervous system are classified according to the degree of their danger according to the WHO classification. See dictionaryforall for Cavernoma in Dictionary.

As a benign tumor, grade I was assigned to the pilocytic astrocytoma. This tumor mainly affects children and adolescents. In this age group, it is the most common brain tumor, accounting for around 30 percent. A distinction is made between optic nerve and brainstem gliomas.

Optic gliomas affect the nerves of the visual pathway and are often associated with hereditary neurofibromatosis type 1. The pilocytic astrocytoma is characterized by the appearance of firm and nodular tumors, which often also have cystic parts. It is an astrocytic tumor with a very low rate of mitosis.

The starting cells form fine fibrillar extensions reminiscent of hair. They are therefore also referred to as hair cells (pilocytes) and give this tumor its name. The tumor is sharply demarcated from the adjacent brain tissue. This is not infiltrated by the tumor, but only displaced.

Causes

Pilocytic astrocytoma is just one form of an astrocytoma. The exact causes of astrocytomas are not yet fully understood. A genetic connection is suspected in benign pilocytic astrocytoma. It is striking that optic gliomas occur particularly frequently in connection with type 1 neufibromatosis.

Neurofibromatosis is a group of genetic disorders that are inherited in an autosomal dominant manner. Type 1 neurofibromatosis, for example, is a genetic defect in the NF1 gene, which is located on chromosome 17. This gene is responsible for encoding neurofibromin.

Neurofibromin regulates the signal transduction protein RAS. In the event of a defect or lack of neurofibromin, RAS is constantly active and thus promotes the formation of neoplasia. In the case of an astrocytoma, the p53 tumor suppressor gene is also defective in more than 50 percent.

Symptoms, Ailments & Signs

The symptoms of a pilocytic astrocytoma also depend on where the tumor is located. The health problems are mainly caused by the displacement of the neighboring brain tissue. When the cerebellum is affected, gait insecurity is particularly important.

If the tumor is localized in the diencephalon, the main symptoms are those associated with the hypothalamus. The hypothalamus regulates, among other things, body temperature, blood pressure, food and water intake, biorhythms and the control of sexual behavior. Tumors in the area of ​​the visual pathway can cause visual disturbances and, in extreme cases, even blindness.

Diagnosis & course of disease

Overall, astrocytomas can be visualized very well using imaging methods such as MRI or CT. With the help of computed tomography (CT), calcifications (calcifications) are also excellently detectable. The behavior of the contrast medium provides a further indication of a pilocytic astrocytoma.

This is uniformly enriched in the center of the tumor while there is a cystic appearance at the edge. The suspected diagnosis can be backed up by a biopsy. Sometimes, however, the diseased tissue can only be examined after the tumor has been surgically removed, and only then can the exact type of tumor be determined. However, the correct suspected diagnosis is often made on the basis of the typical localization of the tumor and the age of the patient.

Complications

Pilocytic astrocytoma is a benign brain tumor that can be easily removed surgically. Complications with regard to possible malignant degeneration hardly ever occur. However, if the tumor is in an unfavorable location, it may not be possible to remove it completely. Then recurrences can be expected.

More serious, however, is the gradual mass of the tumor in the brain. The displacement of neighboring brain structures can sometimes lead to considerable complications, which in extreme cases can even be fatal. The pressure on certain blood vessels in the brain can even lead to the development of a stroke. The impact of a stroke depends on the severity of the cerebral hemorrhage that caused it.

In addition to mild symptoms, which disappear again after the causes of the stroke have been eliminated (removal of the brain tumor), permanent damage can of course also remain or even death can occur as a result of certain areas of the brain dying off. A further complication of a pilocytic astrocytoma is the development of a water head (hydrocephalus). This can occur in the child if the masses of the brain tumor block the liquor drainage within the brain.

In infants or fetuses, the head then expands like a balloon because the skull bones are still soft and malleable. If it occurs later, the intracranial pressure can increase so much that severe headaches, vomiting and seizures occur. If left untreated, a life-threatening herniated brain often develops.

When should you go to the doctor?

Like any brain tumor, the pilocytic astrocytoma should be treated by a doctor who can also confirm the diagnosis. Therefore, going to the doctor is necessary if the patient feels symptoms that could indicate an astrocytoma. The doctor’s visit serves to either initiate early treatment or to calm the patient down, since the symptoms may be due to a comparatively much more harmless illness. The first point of contact is always the family doctor, who can refer you to a radiologist or neurologist if necessary.

Even after the treatment has been completed, a doctor’s visit is mandatory for a pilocytic astrocytoma. They primarily serve to detect a recurrence at an early stage and to treat it promptly. The consequences of therapies can also make a doctor’s visit necessary. Radiation and chemotherapy can cause fatigue or an immune system disorder. For some patients, the diagnosis of pilocytic astrocytoma is so distressing that they need psychological support. Here psychologists, psychotherapists and psycho-oncologists are the appropriate contact persons.

A brain tumor can cause motor and language deficits that can persist even after it has been removed. The doctor is also the right address here. He will identify the link between failures and underlying disease and refer to healthcare professionals. Speech therapists, physiotherapists and ergotherapists are the right address for the patient in this context.

Treatment & Therapy

The treatment of a pilocytic astrocytoma depends on its location and the symptoms that occur. If the location is favorable, the tumor should definitely be removed. There is also a great chance of its complete extirpation here. If this succeeds, the disease will heal completely. However, sometimes the tumor is in such an unfavorable position that an operation is not possible. This often affects brainstem gliomas. Radiation is the method of choice here. In any case, inoperable tumors should be monitored by constant MRI examination. The same also applies to tumors that do not cause any symptoms.

With some tumors it is sufficient for a long time to puncture the fluid-filled cysts. The extensive cysts often take up the most space and have a disruptive effect on the neighboring tissue. Although the tumor is benign, it should be removed in the long term if possible because it can cause irreparable damage to neighboring tissue if it expands further.

The prognosis of pilocytic astrocytoma depends on several factors. These factors include location, rate of growth, general condition of the patient, and the possibility of complete extirpation. Once the tumor has been completely removed, recurrence is ruled out. Malignant degeneration is only extremely rarely to be expected with this type of tumor.

However, if the tumor cannot be completely removed, the residual tumor will grow again. But this also grows very slowly, so that even in these cases the long-term survival rate is very high. Only in the case of inoperable brainstem gliomas is the prognosis poor with a five-year survival rate of a maximum of 30 percent.

Outlook & Forecast

Pilocytic astrocytoma is a brain tumor that always requires close monitoring, whether it has been removed or just being observed. It is a benign, slow-growing tumor that usually has a much better prognosis than malignant brain tumors.

Still, there are complications that can make the prospect more negative. This involves growth over decades, which can lead to the mass gradually becoming too large. Therefore, removal of the often well-defined tumor is often the best option in terms of prospects, if the location of the brain tumor allows it.

The prognosis for pilocytic astrocytoma depends crucially on the location. If the tumor can be removed without affecting important structures, the prognosis is often very good. Conversely, the prospects are somewhat less favourable. The prognosis also depends on whether there is a recurrence after surgery.

Complications must also be included in the prognosis. If the tumor has led to deficits, these are not always completely reversible after the operation. The operation can also lead to limitations, for example in motor skills and speech. Good therapeutic care, for example from a physiotherapist or speech therapist, is also helpful for the patient in terms of future prospects.

Prevention

According to current knowledge, it is not possible to prevent a pilocytic astrocytoma. The disease is hereditary. If the disease has already occurred in the family or relatives, the risk of inheritance to the offspring can be clarified in the context of human genetic counseling.

Aftercare

Follow-up care and rehabilitation are essential components of treatment for pilocytic astrocytoma. One of the primary tasks of tumor aftercare is to detect or prevent a recurrence of the brain tumor at an early stage. In addition, conceivable consequences or side effects should be identified and treated accordingly.

After all, follow-up treatment not only offers support for physical complaints, but also for psychological or social problems that arise from the disease or its treatment. Check-ups play an important role in aftercare.

Magnetic resonance imaging (MRI) is performed no later than three months after the end of therapy. Further check-ups take place at intervals of six to twelve months. After three years, a further follow-up examination is carried out every two years. If necessary, endocrinological, clinical-neurological or ophthalmological examinations can also be carried out.

In the event that the pilocytic astrocytoma could not be completely removed during the operation, the remaining benign tumor grows again, but this happens very slowly. Because of this, the long-term survival rate is relatively high. However, if the astrocytoma can be completely surgically removed, there is usually no recurrence.

Many patients benefit from regular visits to a self-help group during follow-up care. There they have the opportunity to exchange information with other affected people, which is often a great help. It is possible to contact a self-help group during the treatment period.

You can do that yourself

Pilocytic astrocytoma, a benign brain tumor, is removed by surgery as the first choice when the location is favorable. Nevertheless, the patient can also contribute to his well-being through self-help in everyday life. On the one hand, this applies to aftercare, in which stabilization in the physical area is aimed at, but the psychological situation can also be improved through measures. Both will be explained in the following by way of example.

In the physical area after an operation, follow-up care of the wound conditions in cooperation with the treating physicians is important. If the pilocytic astrocytoma was in an area that was damaged by tumor growth or the operation, there are measures for the best possible regeneration that the patient can actively participate in on a daily basis. If the motor skills are restricted, exercises guided by a physiotherapist can also be carried out at home, for example. The same applies to language exercises that the speech therapist recommended for speech disorders.

In general, a healthy lifestyle with enough sleep, sufficient drinking and dosed physical activity is advisable to improve general well-being. If the patient needs psychological support, for example because the diagnosis of a brain tumor is difficult to process, going to a self-help group is often useful. Psychological counseling or talking to friends and family can also help.