Primitive Neuroectodermal Tumor

A primitive neuroectodermal tumor is a tumor in the tissue of the nerves. The disease is one of the embryonic tumors and is referred to by the abbreviation PNET. The majority of cases of primitive neuroectodermal tumors occur in children and adolescents. In principle, a distinction is made between tumors of the central nervous system and peripheral forms.

Primitive Neuroectodermal Tumor

What is a primitive neuroectodermal tumor?

In principle, there are two different forms of the primitive neuroectodermal tumor. The primitive neuroectodermal tumor of the central nervous system was first described in 1973. On the histological level, there are some similarities between the primitive neuroectodermal tumor and so-called pinealoblastomas and medulloblastomas. See healthknowing for What is the Definition of Hypovolemic Shock.

This category of tumors is collectively referred to by some medical professionals as embryonic tumors of the central nervous system. However, there is controversy among researchers about this. About two to six percent of brain tumors that occur in children and adolescents are primitive neuroectodermal tumors.

The second form is represented by the peripheral primitive neuroectodermal tumors. These usually form from tissues that fulfill an ectodermal function. This primarily includes the autonomic nervous system, consisting of the parasympathetic and the sympathetic nervous system. The peripheral variant of the tumor occurs particularly frequently on the chest wall.

The exact name for tumors with this location is Askin tumors. In addition, the tumors are also found on the uterus and ovaries, testicles and bladder as well as lungs and kidneys. Sometimes they also affect the salivary glands of the abdomen and ears as well as the skin. When making a diagnosis, it is often difficult to differentiate between so-called Ewing sarcomas.


The exact causes for the growth and development of primitive neuroectodermal tumors are not yet sufficiently known in view of the current research situation. There is probably an interplay between various factors in the genesis of the disease, with genetic influences also being possible.

Symptoms, Ailments & Signs

The specific symptoms of the primitive neuroectodermal tumor depend primarily on the localization of the tumor. Primitive neuroectodermal tumors in the area of ​​the central nervous system become noticeable, for example, through vomiting and nausea. These signs are most evident in the morning when people are on an empty stomach.

Other serious symptoms are also possible. Some patients lose certain abilities and develop paresis or visual impairment. Sometimes there are even changes in the personality of the affected patient. The symptoms of the primitive neuroectodermal tumor in the central nervous system arise from neurological lesions and deficits when nerve functions are lost.

If the primitive neuroectodermal tumors are located inside the body, other symptoms usually appear. In the case of a disease of the lungs, the patients suffer, for example, from coughing up blood and shortness of breath. Primitive neuroectodermal tumors of the uterus or pancreas initially cause abdominal pain.

Diagnosis & course of disease

The diagnosis of the primitive neuroectodermal tumor is in many cases a lengthy process. Basically, the primitive neuroectodermal tumor is often diagnosed relatively late, since the symptoms are rather unspecific. If people show symptoms, they first consult their family doctor. This will usually refer the patient to a specialist who will carry out further examinations.

At the beginning of the diagnosis, the doctor finds out about the patient’s symptoms, the beginning of the complaints and information about possibly decisive circumstances. It is also important to take a family history, since similar cases in the family increase the suspicion of a particular disease.

During the clinical examination, the treating specialist uses various methods to diagnose the primitive neuroectodermal tumor. With the help of imaging techniques, the doctor examines the tumor and the surrounding areas. He usually uses ultrasound techniques as well as CT or MRT procedures. In this way, indications of the size and extent of the tumor can be obtained.

However, no reliable diagnosis can be made by imaging alone. A biopsy usually provides particularly important information. The doctor removes tissue from the relevant area and orders a histological analysis of the sample. In some cases, such a biopsy is only possible after the tumor has been removed. In the case of primitive neuroectodermal tumors in the central nervous system, on the other hand, a histological examination is often not feasible.


Since this disease is a tumor, the further course and complications of this disease depend very much on the time of its diagnosis. Early diagnosis in particular has a positive effect on the life expectancy of those affected. The patients themselves suffer from this cancer from permanent nausea and vomiting. These symptoms can occur more frequently in the mornings in particular and significantly reduce the quality of life of those affected.

There is also a loss of various motor skills. As the disease progresses, those affected sometimes suffer from paralysis and visual problems. A change in personality can also occur with this tumor and lead to severe depression or other psychological problems. Furthermore, the patients suffer from coughing and shortness of breath.

This usually leads to tiredness and exhaustion in the patient. This tumor is treated with surgery and chemotherapy. Although there are no complications, the tumor may have spread to other parts of the body. The patient’s life expectancy may be reduced.

When should you go to the doctor?

If symptoms such as nausea and vomiting, paralysis or neurological deficits occur repeatedly, a primitive neuroectodermal tumor may be the underlying cause. A doctor’s visit is indicated if the symptoms persist over a period of several days or rapidly increase in severity. If symptoms such as swelling, shortness of breath or coughing up blood appear, you must see a doctor on the same day. It is best for people who have already had a brain tumor to consult the responsible neurologist.

The physician can identify the primitive neuroectodermal tumor using a histological examination. Treatment can then be initiated, which offers good chances of recovery if detected early. If you experience any unusual symptoms that may be related to a brain tumor, your family doctor should be contacted first. If there is a concrete suspicion, the neurologist is the right contact person. Depending on the symptoms, internists, ENT doctors and physiotherapists can be involved in the treatment. In addition, nutritional medicine and alternative medicine can be part of the therapy of a primitive neuroectodermal tumor.

Treatment & Therapy

If possible, the primitive neuroectodermal tumor is removed and then subjected to detailed histological examinations. Primitive neuroectodermal tumors of a peripheral nature are far more easily resected than those of the central nervous system. After the removal of tissue or following a surgical procedure, the affected children and adolescents receive what is known as polychemotherapy.

Various cytostatics are administered. In addition, the patients usually undergo radiotherapy. The prognosis of the primitive neuroectodermal tumor depends on the location, the age of the affected person and the possibility of surgical removal. On average, about 53 percent of patients survive the five-year period.


A targeted prevention of the primitive neuroectodermal tumor is not yet possible because the causes are not sufficiently known. Early diagnosis is therefore particularly important for the patient.


Intensive follow-up care is required after treatment of a primitive neuroectodermal tumor. The actual treatment, such as surgery, chemotherapy or radiation therapy, means there is an increased risk of side effects. These can manifest themselves both physically and psychologically. They often only show up after the treatment is completed.

Another important part of aftercare is the early detection of a possible recurrence in which the tumor shows up again. Therefore, the patient must undergo regular check-ups after the end of therapy. In this way, a possible relapse can be recognized in good time and treated accordingly.

Aftercare takes a lot of patience and extends from childhood and adolescence to adulthood. This applies even if no visible residual tumor can be seen. The first physical examination takes place around six weeks after the end of the tumor therapy. For the first two years, it is usually every six to eight weeks. Later, the examination intervals increase.

Imaging methods such as magnetic resonance imaging (MRI) of the brain and spinal cord are primarily used. Further imaging tests are carried out every three to four months for the first two years. In order to recognize possible late effects, ophthalmological and audiological examinations are also carried out. Electroencephalography (EEG) can also be useful to check brain functions.

You can do that yourself

The tumor develops primarily in children and adolescents. Since they are naturally not yet able to carry out sufficient research into the illness they have suffered, doctors and relatives should inform the offspring extensively and inform them about further developments. Questions and ambiguities should be answered honestly so that no complications or misunderstandings arise.

If the relatives feel overwhelmed in the situation, they should seek help themselves. In addition, it must be checked whether the patient also needs psychotherapeutic support. This can help to better cope with the challenges in everyday life.

One of the possible symptoms of the disease is shortness of breath. This can lead to anxiety or panic reactions. The person concerned must be informed about how best to behave in the event of a reduced oxygen supply. The information can be life-saving in acute situations. Therefore, they should be sufficiently practiced and trained in advance.

In order to strengthen mental strength, zest for life and well-being must be promoted. The leisure activities are to be individually tailored to the wishes of the child and the needs of the organism. A stable environment is important in managing the disease. In severe cases, stress and other disruptive factors can trigger further psychological problems.