Kraniopharyngeom

Craniopharyngioma: description

The craniopharyngioma is a benign tumor in the head. It develops from cell debris from embryonic development. Since the craniopharyngioma grows very slowly, the first symptoms usually appear in children between five and ten years old. But even adults can get this tumor. He occurs most often between their 50th and 75th year. Overall, the craniopharyngioma is rather rare. In children it accounts for five to ten percent, in adults only three to five percent of all tumors in the skull.

Physicians distinguish two forms of craniopharyngioma:

• The adamantinomatous craniopharyngioma mainly affects children and adolescents. It is riddled with many small, often fluid-filled inclusions. In addition, horny cells and lime occur, which can often be seen well in imaging procedures.
• The papillary craniopharyngioma occurs mainly in adults. It only rarely hardens or calcifies.

Despite their differences, both tumor types are treated equally.

Craniopharyngioma: symptoms

Although it is basically a benign tumor, the craniopharyngioma may sometimes trigger dangerous symptoms depending on its location and size. For example, if it presses on the optic nerves, vision problems can arise. Most of the time, the outer visual fields are initially absent. Large tumors can even blind them.

Early signs of a craniopharyngioma often involve changes in personality, concentration, and memory, often months before diagnosis. In children, the tumor may be the first to become noticeable by a growth disturbance or the absence of puberty. The reasons for this are disorders in the hormone balance:

Hormonal disorders caused by a craniopharyngioma

The craniopharyngioma may disturb the function of the pituitary gland (pituitary gland) and that of its superordinate center (hypothalamus). Both produce hormones, which in turn regulate the hormone production of other glands in the body (such as the thyroid gland). Thus, the craniopharyngeoma can ultimately influence the formation of various hormones in the body and subsequently cause a wide variety of ailments. The most common ones include dwarfism, obesity, diabetes insipidus and eating disorders.

Growth disorders such as small or large growth can occur when the craniopharyngioma affects the production of growth hormone in the pituitary gland. In adults, this can lead to disorders of fat metabolism and acromegaly (enlargement of toes, fingers, chin and nose, hypertension, increased sweating, etc.).

Overweight and underweight, osteoporosis and increased or decreased hairiness are possible consequences if the craniopharyngioma disturbs the production of the stress hormone cortisol in the adrenal glands by impairing the pituitary gland.

The craniopharyngioma can also interfere with the fluid balance of the body: it is regulated by the antidiuretic hormone (ADH), which is produced in the hypothalamus, stored in the pituitary gland and then released into the blood as needed. It ensures that urine does not excrete too much water. In this way, ADH also affects blood salt concentration and blood pressure. If the tumor triggers an ADH deficiency, diabetes develops insipidus: In this hormone deficiency disease excreted many liters of water-clear urine (polyuria) and must, in order not to dry out, drink a lot (polydipsia).

Also, the secretion of female (estrogen) and male (testosterone) sex hormones, which is controlled by the pituitary gland, can affect a craniopharyngioma. Possible consequences include that puberty is delayed or absent, or the menstrual period is disturbed or fails.

By influencing the pituitary gland, a craniopharyngeoma can also impair the function and hormone secretion of the thyroid gland. For example, excess thyroid hormone can cause palpitations, diarrhea, and excessive sweating. If, on the other hand, too few thyroid hormones are produced, many metabolic processes freeze. Those affected are cold, constipated, tired and without power.

General symptoms of a brain tumor

As with other brain tumors, craniopharyngioma may cause symptoms such as headache, nausea, vomiting, muscle paralysis and hydrocephalus. However, such symptoms usually only appear in large tumors.

Craniopharyngioma: causes and risk factors

The craniopharyngioma is the result of cells that have formed a passage between the brain and the throat (the craniopharyngeal duct) during embryonic development. By sudden, uncontrolled proliferation, a residual craniopharyngioma may result from the remainder of these cells in children and adults. It grows in the so-called Turkish Saddle (Sella turcica). This is a bony hollow of the anterior skull base, in which the pituitary gland lies. In the immediate vicinity, the two optic nerves intersect. Most of the symptoms of this tumor are due to crowding out of neighboring structures.

Why degenerate the cell remains and form a Kraniopharyngeom is not yet known.

Craniopharyngioma: examinations and diagnosis

If there is a suspicion of a craniopharyngioma, it is especially important to visit an endocrinologist, a specialist in hormone disorders. He will be described in detail the patient’s complaints in order to gain any indication of a disorder of certain hormones. Also informative is the measurement of various hormone concentrations in the blood, saliva or urine.

The most important imaging technique in a craniopharyngioma is magnetic resonance imaging (MRI). The exact location and size of the tumor can be determined. If an MRI is not possible for certain reasons (for example, because the patient suffers from claustrophobia or has a pacemaker), computer tomography (CT) can alternatively be performed. Again, a craniopharyngioma, including its typical calcifications, can be accurately represented.

An examination at the ophthalmologist serves the clarification of visual disturbances. A visit to the neurologist (neurologist) is required if the patient has an increased intracranial pressure or cranial nerve failures.

Craniopharyngioma: treatment

Therapeutic options for a craniopharyngioma include drug treatment, surgery and radiotherapy. The exact treatment plan is individually adapted to the patients.

Drug treatment in a craniopharyngioma is not aimed at eliminating the tumor (this is not possible with medication). Rather, it compensates for a tumor-related lack of hormones (hormone replacement therapy). For example, ADH, thyroid, growth, sex and stress hormones can be replaced by drugs. The exact dosage is not quite easy, because the individual hormones formed during the day and in different amounts depending on the particular phase of life. When dosing this should be considered as optimal as possible. This requires regular monitoring of the treatment.

During surgery, an attempt is made to remove the craniopharyngioma as completely as possible. Access is preferably via the nose (transnasal surgery).

Sometimes a complete removal of the tumor is not possible, because the risk of complications would be too great (development of personality disorders, permanent diabetes insipidus, etc.). So you only remove part of the tumor and treat the residual tumor with radiotherapy. Irradiation may also be useful in the case of a recurrent craniopharyngioma (recurrence) and for emptying the fluid-filled cavities (cysts) in the tumor.

Examination and treatment

Further information on examination and treatment Read in the article Brain Tumor.

Craniopharyngioma: disease course and prognosis

The prognosis of a craniopharyngioma depends largely on whether it is detected early and can be completely surgically removed. In the long term, it is very good for small, compact and easily removable tumors. However, 80 to 90 percent of patients have to compensate for existing hormone losses for life using hormone replacement products.

If a craniopharyngioma is treated by surgery and subsequent radiation, the cure rate is 70 to 83 percent after ten years. However, a long-term consequence of the radiation can also be hormone failures, which have to be treated with medication throughout their lifetime.

Disorders of vision, memory and memory, which have already existed before the surgery, can usually not be repaired by the procedure.

About 30 percent of patients with a craniopharyngioma are severely obese. The risk of complications such as diabetes (diabetes mellitus) and heart disease is therefore high.

As a general rule, patients with a craniopharyngioma need lifelong aftercare – not only because of the hormone replacement therapy that is required in many patients and the risk of subsequent obesity. Not to be underestimated is the high recidivism rate at one Kraniopharyngeom.