Radiotherapy uses high-energy rays to destroy cancer cells while causing the least possible damage to normal cells.
Radiotherapy can be given in two different ways:
- From outside the body
- From the inside, by placing a radioactive material near or in the tumor.
The treatment is given in the hospital's radiotherapy department. Each treatment lasts 10-15 minutes and takes place every weekday, with weekends set aside to rest.
Your doctor will discuss your treatment and the possible side effects with you.
External radiotherapy must be carefully planned in order to ensure that it is as effective as possible.
On your first visit to the radiotherapy department, you will have a CT scan done or you will lie down below a machine that will take x-rays of the area to be treated.
You may have small marks made on your skin (tattoos) to help the technician find the position more precisely so that the rays can be directed to this area. These marks must remain visible throughout the treatment. These are extremely small permanent marks, and you won't have these done without your consent.
In some patients, gold "seeds" are placed in the prostate during an outpatient visit. These seeds are used by the surgeon as markers to help locate the area to be treated in case the intestines are full. This reduces the risk of delivering radiation to areas located near the prostate.
In treatment sessions, the technician will carefully place you so that you are comfortable, as you must remain still during the treatment. Radiotherapy isn't painful. During the treatment you will stay in the room alone, though you can talk to the technician monitoring you from an adjacent room.
- 3-D conformal radiotherapy (3D-CRT):
This type of radiotherapy uses images of the prostate taken from different points, thus making the treatment more effective and causing less damage to surrounding tissues.
- Intensity-modulated radiotherapy:
This is an advanced form of 3-D therapy. With this type of radiotherapy, the machine moves around the patient as radiation is being emitted. Also, the strength (intensity) of the rays can be adjusted in the moment to limit the dose delivered to more sensitive tissue.
- Stereotactic body radiotherapy:
With this type of radiotherapy, high doses of treatment are delivered to a specific area. It is also known by teams of specialists as: Cyberknife®, gamma-knife®, and clinac®.
The advantage of this type of radiotherapy is that it is given in just a few days.
Side effects of external beam radiotherapy:
- Irritation in the rectum and anus; diarrhea also develops
- Bladder irritation
- Reddening of the area
Internal radiotherapy (brachytherapy):
- Low-dose radiotherapy (LDR)
This is used to treat tumors in initial stages. Brachytherapy uses small particles called "seeds" which are placed directly in the prostate.
These seeds gradually liberate the dose over a period of 6 months. There is no risk of people in your surroundings being affected.
It is recommended for use in patients with urinary problems and patients who have had a previously transurethral resection.
- High-dose radiotherapy (HDR)
This involves inserting some hollow needles and tubes through the skin in the direction of the prostate. The radioactive material is inserted through these tubes (three treatments over two days).
When the treatment is finished, the tubes are removed and no radioactive material is left in the prostate glad. People may feel pain or develop swelling in the area for the first few days; also, urine may turn a reddish brown color.
This method can be combined with external radiation. The big advantage of the procedure is that most of the radiation is concentrated in the prostate itself and does not affect the urethra or the tissues that surround the prostate, such as nerves, bladder, and rectum.
Side effects of internal beam radiotherapy:
- Intestinal problems: pain in the area of the rectum, and diarrhea.
- Problems urinating: urinary incontinence
- Erection problems.