What is brain tumor?
A brain tumor is a mass or an abnormal cell growth inside the brain. There are different types of brain tumors. Some of the brain tumors are noncancerous (benign), and others are cancerous (malignant). Brain tumors can originate in the brain or cancer can start in other parts of the body and spread to the brain. It can vary greatly how quickly a brain tumor can grow. The growth rate and location of a brain tumor determines the extent of effect on the functioning of nervous system.
Treatment options for brain tumors depend on the type of tumor, size and location of the tumor. These tumors are categorised as primary or secondary. Primary brain tumor is the one which originates in the brain and many of them are benign. A secondary brain tumor, also called a metastatic brain tumor develops when cancer cells spread from another organ to brain such as lung or breast.
A primary brain tumor is a tumor which begins in the brains and is also identified as “low grade” or “high grade.” A low grade tumor develops slowly and may turn into a high grade tumor which more likely to develop faster. Secondary brain tumors are far more common in adults than primary tumors.
A secondary brain tumor is a cancerous tumor that starts in another part of the body, including the breast, lung, or colon, and then spreads to the brain. If cancer spreads to meninges and the cerebrospinal fluid (CSF) it is referred to as leptomeningeal metastases or neoplastic meningitis. In patients with leukemia, lymphoma, melanoma, breast cancer, or lung cancer, this disease occurs more often.
There are different types of tumors that can begin in the brain or spinal cord. It is unlikely that both of these different tumors would have the same causes, but may have certain things in common. Most of the brain tumor causes is not well known, and very few risk factors exist.
What causes brain tumor?
Normal human cells develop and function mainly based on information found in the DNA of each cell. Like other cancers, brain and spinal cord cancers are caused by changes in the DNA inside cells. DNA is the chemical which makes up our genes and which regulates the cell function. Typically, we look like our parents, because they are our DNA source.
Some genes regulate our cells as they develop, divide them into new cells and die:
- Some genes which help cells to develop, divide and remain alive are called oncogenes
- Genes that help to regulate cell division, repair mistakes of DNA or destroy cells at the right time are called tumor suppressor genes.
DNA modifications that turn on oncogenes or turn off tumor suppressant genes may cause cancer. Such gene changes may be inherited from a parent, but they do occur more frequently during the lifetime of an individual.