Brain Tumors Causes

Primary brain tumors—which originate in the brain—form when the DNA in brain cells mutates, and these cells reproduce unchecked. Abnormal cells begin to accumulate, and form a tumor within brain tissue. The specific causes of primary brain tumors are unknown, but certain environmental and hereditary factors may increase the risk. Secondary brain tumors, on the other hand, are caused by the spread of cancer cells to the brain from somewhere else in the body.

Primary Brain Tumor Causes

Researchers have determined that both environmental and genetic factors can contribute to primary brain tumor development. In particular, exposure to certain types of radiation and chemicals are associated with an increased risk of developing a brain tumor. These include:

  • Formaldehyde
  • Ionizing radiation
  • Vinyl chloride.

You are also more likely to develop a brain tumor if you have a family history of the disease, though doctors are unsure exactly which genes contribute to brain tumor risk.

Chemical Causes of Tumors

Research suggests that pathologists and embalmers who extensively work with formaldehyde, a toxic, cancer-causing compound, have an increased risk of brain cancer. Current practices involve the use of formalin, which is diluted formaldehyde, and is a safer tissue fixative.

Vinyl chloride, another toxic carcinogen, is a chemical used to manufacture plastics. Manufacturing plants may leak vinyl chloride into the air or water and, if not disposed of properly during manufacturing, it can leak into the environment. People who work in or live near manufacturing plants that use vinyl chloride are at higher risk of developing brain tumors than the general population.

Radiation and Brain Tumors

Exposure to ionizing radiation, particularly for people working in the nuclear industry, is one of the only environmental factors proven to increase one’s risk of developing a brain tumor. Radiation leads to mutations in DNA that cause cells to reproduce out of control and form a tumor in brain tissue.

Genetic Brain Tumor Causes

Genetically inherited brain tumors are very rare; less than 10 percent of brain tumors are attributed to heredity. Genetic factors, though, can make an individual more prone to developing a brain tumor.

The function of tumor suppressor genes is to keep malignant cells from reproducing and to allow for the repair of DNA. Genetic mutations and deletions in these genes are associated with inherited brain tumors. These inherited diseases include:

  • Multiple endocrine neoplasia — type 1 (pituitary gland tumors)
  • Neurofibromatosis type 2 (brain and spinal cord tumors)
  • Retinoblastoma (malignant retinal glioma, or tumors originating from glial cells)
  • Tuberous sclerosis (primary brain tumors)
  • Von Hippel-Lindau disease (retinal tumor, central nervous system tumors).

Secondary Brain Tumor Causes

Because secondary brain tumors metastasize from cancerous cells in another part of the body, causes are attributed to the nature of the original cancer. People with a history of a type of cancer that commonly spreads to the brain are at an increased risk of developing a secondary brain tumor. Cancers that most often spread to the brain include:

  • Breast
  • Colon
  • Kidney
  • Lung
  • Melanoma.

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