Radiation Oncology - Treatment
What to Expect -
* Treatment Preparation
- Most cases require one or more treatment preparation steps called simulations. These are performed by the Radiation Therapists. Special molded devices that help the patient maintain the same position every day are sometimes developed at this point.
Special molded devices
- Colored, semi-permanent ink and / or small permanent tattoos are used to mark the skin, to assist in aligning the radiation equipment with the target area. X-rays may be taken in preparation for a treatment planning CT scan. The treatment simulation session might take from thirty minutes to an hour and the CT scan might take an additional 15-30 minutes.
- Following the simulation, the Medical Dosimetrist and Oncologist perform your custom designed treatment plan. This process may take several days.
- Once your plan is complete, the Medical Radiation Physicist will perform the quality assurance process to verify the accuracy of the plan and the calculations.
- After, our patients will be given an appointment to return to our department to begin radiation treatments.
* Treatment Delivery
- The first treatment session is usually 15 minutes longer than subsequent ones so that initial X-ray verification films and checks can be done on the treatment machine. A typical daily treatment session lasts about 15 minutes.
- In the treatment room, the radiation therapist uses the markings made during the simulation process to locate the treatment area. Sometimes, special molded devices are used to help with positioning on the treatment table.
- Once the patient is set up as their custom plan indicated, the radiation therapist leaves the treatment room before the machine delivers any radiation.
- The radiation is controlled from the area outside the treatment room. During radiation delivery, while alone in the room, our patients are monitored on two television screens, and can be heard by the therapist through an intercom.
You will be monitored during radiation delivery
- Receiving external radiation treatments is painless, just like having an X-ray taken. You do not see or hear the radiation and do not feel it going through you. You only know when the treatment is on by indicator lights and a buzzing sound that the machine makes when radiation is being delivered.
Treatment Sites -
* Hodgkin's Disease
What treatment delivery options are available at our centers -
or ‘Three-dimensional' treatment is an advanced form of radiation therapy adopted as our gold standard at both facilities it uses CT or CAT scan images to plan, and then deliver tightly focused radiation beams to cancerous tumors. The number and size of radiation beams and the direction from which it is aimed can be customized to give a high radiation dose to the tumor while minimizing the radiation dose of surrounding normal tissues.
* IMRT or ‘Intensity-modulated radiation therapy‘. It is a new form of radiation therapy that uses CT images to plan, and then deliver hundreds of tightly focused radiation beamlets to cancerous tumors. The intensity (or amount) of the radiation is being changed during treatment to give a higher radiation dose to the tumor while minimizing the radiation dose of surrounding normal tissues. An analogy might be like having hundreds of bicycle spokes (radiation beamlets) going through your body, and the area where the spokes all meet is at the area where all the radiation adds together to kill the tumor.
* Image Guided Radiation Therapy (IGRT)
IGRT is at the forefront in radiation cancer treatment. IGRT is the next step above and beyond IMRT combining the benefits of the advanced treatment technology with an increased accuracy. Some tumors (such as the prostate) move from one treatment session to another as a result of normal internal organ action (digestion, elimination, and breathing). In the past, we treated areas larger than the prostate by as much as 1 cm to account for this normal movement and inherent daily setup differences. IGRT provides us with capability to target the prostate with an accuracy to within 0.2 cm.
At our centers we have adopted IGRT using ultrasound imaging technology for the treatment of all of our prostate cancer patients, and many of the pelvis patients. Each day, just prior to radiation treatment, the radiation therapists on the treatment unit will image the patient's prostate with an ultrasound machine to see how much the prostate has moved due to bladder or rectal filling. When required, the therapist will shift the patient to realign the treatment so that the radiation is directly targeting the prostate. By knowing the exact the location of prostate each day, the radiation oncologist will be able to eventually reduce field margins to a minimum, allowing us to increase tumor doses and reduce side effects.
* Stereotactic Radiosurgery - This treatment has been used as an alternative to brain surgery over the past 30 years allowing very precise delivery of Radiation to treat small abnormalities, tumors or other functional disorders, such as Glioma, Acoustic Neuroma, AVM malformations, Meningioma, and metastatic carcinoma, while sparing the normal brain tissue. The entire treatment is given in a single dose (Radiosurgery). Because a metal frame is fixed to the patient’s head, this type of treatment is the most accurate available
* Superficial X-Rays - Superficial radiotherapy is highly effective in the treatment of certain basal cell and squamous cell carcinomas of the skin. Low energy x-ray radiation is used to kill cancer cells on the skin and takes less than 5 minutes per day. The machine appears similar to an x-ray arm located in a dental office.