1 There are over 200 types of cancer.  Anything that may cause a normal body cell to develop abnormally potentially can cause cancer; general categories of cancer-related or causative agents are as follows: chemical or toxic compound exposures, ionizing radiation, some pathogens, and human genetics.
Chemotherapy uses anti cancer (cytotoxic) drugs to destroy cancer cells. For some types of brain tumour you may have chemotherapy after surgery, to try to prevent the tumour from coming back. Chemotherapy is sometimes given with radiotherapy and for some months afterwards to help people to live longer.hemotherapy works very well for some types of brain tumour but it does not work for all of them. You may have some types of chemotherapy in cycles. You have the drugs for a few days every few weeks.
Some people with Stage 0 (DCIS) and most people with Stage 1 invasive cancer and higher, who have had a lumpectomy, can expect radiation therapy to be a part of their treatment regimen. Most radiation therapy is administered by a radiation oncologist at a radiation center and usually begins three to four weeks after surgery. The radiation is used to destroy undetectable cancer cells and reduce the risk of cancer recurring in the affected breast. There are two main kinds of radiation therapy that may be considered, and some people have both. External Bearm Breast Cancer Radiation (Traditional cancer-killing rays delivered by a large machine)