What is external-beam radiation therapy and conformal external-beam radiation therapy? What are the side effects of EBRT?
External-beam radiation therapy (EBRT) is the use of radiation therapy to kill or inactivate cancer cells. The total radiation dose is given in separate individual treatments, known as “fractionation.” Cancer cells are most sensitive to radiation at different phases in their growth. By giving the radiation on a daily basis, the radiation oncologist hopes to catch the cancer cells in the sensitive phases of growth and also to prevent the cells from having time to recover from the radiation damage. Conformal EBRT uses CT images to help better visualize the radiation targets and the normal tissues; with three-dimensional images, the radiation oncologist can identify critical structures, such as the bladder, the rectum and the hip bones. This allows the radiation oncologist to deliver more radiation to the prostate tissue but decrease the amount of normal tissue that is irradiated. The advantage of conformal EBRT over EBRT is that conformal EBRT causes less rectal and urinary irritation. T
