Brain Tumor: Signs, Types, and How It Is Detected

A brain tumor is a growth of cells in brain tissue that divide abnormally and uncontrollably. Below is what is known about the types of such neoplasms, their signs, and methods of detection, with notes on where the data are confirmed and where they remain uncertain.

What a brain tumor and brain cancer are

Primary tumors develop from brain tissue, its membranes, or cranial nerves — for example, gliomas and glioblastomas. Secondary, metastatic, tumors enter the brain from another organ. In the UK, more than 12,000 primary brain tumors are detected annually, about half of them malignant; many more people are diagnosed with a secondary tumor.

The cause of most brain tumors is unknown. Risk factors include age (more often 85–89 years), ionizing radiation (a very small proportion of cases: radiotherapy and, rarely, CT or X-ray of the head), and hereditary syndromes: tuberous sclerosis, neurofibromatosis type 1 and type 2, Turner syndrome. People of any age are affected, including children, but more often older adults.

Benign and malignant brain tumor

Tumors are assessed by grade: grades 1–2 are low, grades 3–4 are high. A benign tumor grows slowly and recurs less often; most grade 1–2 tumors are not cancerous. Malignant tumors are usually classified as grade 3–4, and they recur more often. Gliomas can be both low grade (grade 2) and high grade (grades 3–4).

The widespread belief that any tumor in the head is cancer is not supported by the data: about half of primary brain tumors are malignant, and most grade 1–2 neoplasms are noncancerous. Treatment of benign tumors is often successful, and full recovery is possible, although a small risk of recurrence remains — in that case, regular follow-up examinations are needed.

Signs of a brain tumor

Symptoms depend on which part of the brain is affected. The most common are:

• headache, often in the morning;
• seizures;
• persistent nausea, vomiting, and drowsiness;
• mental changes: memory problems, personality changes;
• progressive weakness or paralysis on one side of the body, visual and speech disturbances.

In the early stages there may be no symptoms, and they can appear very slowly. In addition to focal impairments — of sensation, memory, coordination, hormonal levels — general cerebral symptoms increase over time due to impaired hemodynamics and increased intracranial pressure.

What stage 4 brain cancer means

For brain tumors, a malignancy grade from 1 to 4 is usually used rather than a stage. Grades are assessed by growth rate and the likelihood of recurrence after treatment; grades 3–4 are high, and such tumors more often recur after treatment. The prognosis depends on age, tumor type and location, treatment effectiveness, and general condition. On average, about 17 out of 100 people with a malignant brain tumor live 5 years or longer after diagnosis; exact figures for specific types are difficult to predict — tumors are rare and diverse.

Spinal cord tumor: how it differs from a tumor in the head

Tumors of the central nervous system are classified together: the WHO histological classification describes more than 100 subtypes grouped into 12 categories. The picture depends on localization: when the spinal cord is affected, peripheral paralyses with reduced muscle tone develop, while damage to motor pathways in the brain produces central paralyses with increased tone.

How a brain tumor is detected and when to see a doctor

Diagnosis includes a neurological examination, MRI, CT, and biopsy. If a more likely cause of the symptoms cannot be found, the person is referred to a neurologist for further evaluation and examinations, including brain imaging. The reason for consultation is the listed symptoms — especially a headache that is unlike the usual one or that worsens over time.

A headache alone is not a reason to call an ambulance; 103 or 112 are needed for sudden weakness or paralysis on one side of the body, sudden speech or vision impairment.

This material is for reference: it describes signs and principles of diagnosis but does not replace a doctor's consultation — the decision on examination is made by a specialist.

This content is for reference and does not replace a doctor's consultation. Medical disclaimer