The thalamus is a mass at the top of the brain stem that works with the cerebrum to control muscle coordination. It also acts as a relay station for the cerebrum's sensory center. Malignant tumors within this area of the brain are often considered inoperable.
Thalamic tumors are diagnosed through a CT scan. Tumors of the thalamus account for up to 5 percent of all brain tumors.
A tumor in the thalamus presents with a decreased or impaired sense of touch, often on one side of the body, and is accompanied by headaches due to increased intracranial pressure. Symptoms also include abnormal involuntary eye movement (nystagmus), swollen optic nerves and speech difficulties.
Tumors of the thalamus affect muscle movements. A person might experience difficulty walking, speaking and performing day-to-day functions. Tumors can be benign (noncancerous) or malignant (cancerous).
Tumor size varies. The larger the tumor is, the more intracranial pressure presents within the brain. A patient experiences more symptoms as pressure increases.
Treatment depends on the size, scope and location of the tumor. Noncancerous tumors can be surgically removed to relieve symptoms. Cancerous thalamic tumors generally are not removed surgically; instead, they are treated with chemotherapy and radiation.