The primary symptoms of intracranial tumors can vary to a great extent depending on localization, type and rate of growth. The time from the appearance of the first symptom until the patient is diagnosed can often say something about the rate of growth and thereby the degree of malignancy. Sometimes, bleeding is seen in the tumor. The symptoms can then develop just as quickly as for a stroke.
Increased intracranial pressure
Increased intracranial pressure is due to the mass effect of the tumor, the edema around the tumor, and/or secondary hydrocephalus development.
The cardinal symptom is headache, which often arises gradually and is most pronounced in the morning. It will frequently be accompanied by nausea and vomiting in the morning and, in advanced stages, impaired consciousness.
In the event of increased pressure, there is a risk of herniation through the tentorium, which is characterized by:
- extension spasms
- oculomotor nerve dysfunction
- respiratory failure
Two-thirds of the patients with slow-growing and 1/3 of those with fast-growing tumors have had one or more epileptic seizures. Patients who have experienced epileptic seizures should therefore always be scanned with regard to an intracranial tumor.
Focal neurological impairment
Symptoms such as paresis, contraction of field of vision and apraxia are common and often indicate the localization of the tumor. Often there is an unspecific or generalized impairment of cerebral function with symptoms such as, increased fatigue, irritability, psychiatric symptoms or reduced intellectual-functioning levels.
Hormonal disturbances are especially related to pituitary gland tumors and other tumors in the same region, e.g. craniopharyngiomas.
- Hyperprolactinemia with pituitary adenoma is caused either by a prolactinoma or constriction of the pituitary stalk. Hyperprolactinemia in women causes menstrual disturbances. Other symptoms are infertility, galactorrhea, reduced libido and impotency.
- Hypersecretion of growth hormone produces acromegaly in adults.
- Hypersecretion of ACTH produces Cushing's syndrome.
Symptoms and signs of pathological hormone production are sometimes neglected by the patient or overlooked by the doctor. The tumors are then first diagnosed when they have become so large that they impair the vision. This not unusual for prolactin-producing tumors in men, who often ignore impotency and reduced libido. For non-hormone producing macroadenomas, the most common presenting symptoms are the loss of normal pituitary gland function and contraction of field of vision/reduced vision.
Bleeding in pituitary tumors occurs with rapidly occurring headaches, cranial nerve palsies and possibly fever. This is called pituitary apoplexy.