External beam radiation therapy (EBRT) remains a prostate cancer treatment staple for men whose cancer is organ-confined. Working closely with radiation oncology colleagues, the Doctors of Academic Urology & Urogynecology of Arizona will deem if a form of external beam radiation therapy, like that of three-dimensional conformal therapy and intensity-modulated radiation therapy, is right for you. Regardless of the chosen methodology, the end goal remains the same: destroying and preventing the growth of cancerous prostatic tissue through the application of targeted beams of energy.
Radiotherapy inhibits the growth of cancer by damaging the DNA of cells. When these cells then divide, they die, resulting in the reduction of tumor size and the prevention of metastasis. To limit the damage to surrounding tissues and organs, the precise location of the cancerous growth is carefully mapped and targeted using advanced external beam radiation technology. Radiotherapy sessions for prostate cancer are typically administered five days a week for a period of six to nine weeks and are conducted on an outpatient basis.
Three-dimensional Conformal Radiation Therapy (3D-CRT):In this form of prostate cancer radiotherapy, a computed tomography (CT) scan of the cancerous prostate gland and surrounding tissues is taken, producing a three-dimensional image of the pelvic region. Computer-controlled linear accelerators then deliver precise beams of radiation that are conformed to target the area of malignancy. As the beams of radiation are focused, higher dosages of radiation can be delivered without significant damage to the surrounding cells.
Intensity-Modulated Radiation Therapy: As with 3D-CRT, computer-controlled linear accelerators deliver precise beams of energy to targeted cancerous tissue in an intensity-modulated radiotherapy session. However, in this form of radiotherapy, the strength of the beam is modified according to the extension of the disease throughout the prostate. Increased levels of radiation are delivered to areas of the gland that are highly affected by cancer and a lesser dosage is administered to those areas showing limited cancerous growth. The goal of this variation of external beam radiation therapy is to successfully eradicate the cancer while preserving healthy cells and thus, reducing the unwanted side effects of radiation therapy.
Traditionally, external beam radiation therapy is used as a primary form of prostate cancer treatment when the disease is organ-confined. In this stage, radiation can be curative. Additionally, it is not uncommon for radiation to be used in addition to other forms of prostate cancer treatment, such as hormone therapy and prostate cancer surgery. A patient may experience side effects throughout the duration of treatment. These include, but are not limited to, diarrhea, fatigue, and rectal irritation. Blood may also be seen in the urine, feces, and semen. Additionally, a patient may experience a temporary loss of continence, including the frequent and urgent need to urinate. The aforementioned side effects typically subside after the end of treatment.