health

The causes of primary tumors of the brain were not completely understood
as of 2008; most researchers, however, think that defective genes are
responsible. Other theories include viruses, exposure to certain chemicals,
and disorders of the immune system.
Secondary brain tumors result from the spread of cancer that began
elsewhere in the body, with lung cancer the most common type. Brain
tumors can also develop from cancerous cells from the breast, kidneys,
colon, or skin. The cancerous cells break off from the primary tumor and
travel to the brain through the bloodstream.
The symptoms of a brain tumor may result from a primary tumor;
they may also be the earliest symptoms of a cancer that developed in
another organ. The most common warning signs include:

• Headaches, which may be most severe in the morning, new for the
  person, or grow worse over time
• Nausea and vomiting
• Problems with eyesight, such as seeing double or having blurred
  vision
• Loss of sensation in an arm or leg, or weakness or paralysis on one
  side of the body
• Difficulty thinking or speaking, having trouble finding words
• Memory loss, confusion, or disorientation
• Seizures or convulsions
• Personality changes
• Hearing loss
• Difficulty walking normally, losing one’s balance, frequent falls
• Weakness and fatigue
• Hydrocephalus

Symptoms of brain tumors in small children may include:

• Increased head size
• In infants, bulging of the soft spot at the top of the skull
• Breathing problems or problems swallowing