Radiation therapy is an integral component of most cancer treatment plans, yet many misperceptions about its application and possible side effects exist.
Your radiation oncologist will use scans – known as simulation – to create your custom radiation plan. When simulating, you’ll be placed in a cool and dark room; markings from scanning may appear on your skin while body molds or masks might also be utilized.
Type of Cancer
Radiation therapy works to target cancer cells by damaging their genetic material, stopping them from proliferating further and spreading. Radiation can also kill cancer cells that have already begun dying off. To ensure maximum effectiveness in treating a tumor effectively and to provide for patient safety during therapy sessions, radiation oncologists carefully plan how much radiation therapy will be necessary while also taking into account medical history and other conditions as part of their assessment.
Some forms of cancer are best treated through a combination of radiation and surgery. For instance, if your doctor recommends surgery to remove a lung or brain tumour, they may also suggest preoperative radiation to shrink its size (this process is known as neoadjuvant therapy).
External beam radiation therapy, the more commonly employed form of radiation treatment for cancer patients, uses external radiation beams emitted from outside to direct beams directly toward cancer sites in the body for quick and painless treatments.
Before beginning treatments, your doctor will use a CT scan to accurately locate and size up the cancer. Next, your radiation oncologist and radiation therapist will devise a strategy for positioning you during treatments; you might receive a plastic mask or mould tailored for your head, face, arm or leg with marks or labels to indicate which area(s) need treatment. You will then lie on a treatment table while being assisted by radiographers to get into position before lying back down on it; they’ll ensure each time that machine aims at correct area; total number of treatment sessions depend on cancer type as well as severity of symptoms or cure(s).
Radiation treatment may cause new cancers to form elsewhere on the body, known as radiation-induced malignancy. This typically affects tissues adjacent to where radiation was applied; common forms include leukemia (blood cancer), sarcomas (a type of bone and soft tissue cancer), and thyroid cancer – these often appear immediately or months or years after radiation treatments have taken place.
Tumor Location
Radiation therapy uses high-energy rays to kill cancer cells and relieve symptoms. It may be used as the main therapy to shrink or eliminate tumours (curative radiotherapy), or used alongside other treatments (neoadjuvant radiotherapy). Furthermore, radiation can also be used post surgery to lower risks of cancer coming back (reduce risk) or ease pain and other symptoms caused by advanced cancers (palliative radiotherapy).
Location is everything when it comes to how the body responds to radiation therapy and whether any healthy tissue is affected, and thus known as target volume. Your doctor and radiation therapist will use information gleaned from tests and scans to plan your radiotherapy so as to deliver maximum possible dose while minimising damage to nearby healthy tissue. They may use markers on an area being treated or make molds of you head, arm, or leg so the same treatment area covers every time you visit hospital for therapy.
Radiation therapy typically is administered from outside the body via a machine that directs beams of radiation toward your tumour. You lie on a table during treatment and may be monitored through windows or cameras; for those receiving brain tumor treatment, however, a mask must cover their whole head to protect other parts of their body from radiation exposure.
Tumors located in the frontal lobe can negatively impact memory, emotional expression and judgement as well as balance, speech and vision issues.
The cerebellum, located beneath the occipital lobes of the brain, regulates movement and balance. Additionally, it acts as a relay station between upper and lower parts of the brain and spinal cord. If there is an injury in this area, double vision, weakness on one side of body and balance problems may arise as a result. A tumor in this region could cause double vision as well as lead to double-vision, weakness on one side of body or problems with balance.
Dose
Radiation oncologists utilize a computerized system to develop the exact dose for each patient. This process, known as treatment planning, must consider several factors, such as type and location of tumor as well as overall health considerations.
Your doctor must also determine how long you will receive radiation therapy each week, such as for head or neck cancer treatment. A radiation oncologist may suggest a course of treatment lasting eight weeks with one to five minute sessions lasting 1-5 minutes each time. In order for radiation to reach its intended target effectively, your therapist may place you in a head frame or similar device to ensure you remain still.
At each session, your radiation oncologist will use multiple beams of radiation directed towards your tumor from various angles. Each beam serves a distinct purpose; to ensure each dose reaches the tumor and that there is no overlap among beams, they adjust intensity settings using sophisticated computers.
Radiation oncologists typically recommend conventionally fractionated treatments, in which radiation doses are administered over multiple weeks or months to allow healthy tissue to heal between treatments, making the radiation even more effective against tumor cells.
Your radiation oncologist may suggest hyperfractionation as a means to accelerate or accelerate treatment, by giving larger daily or weekly doses of radiation over a shorter duration period in order to shorten treatment timeframes.
Radiation therapy is also widely used for non-malignant conditions like trigeminal neuralgia, acoustic neuromas, severe thyroid eye disease and pterygium as well as being an integral component of bone marrow transplant surgery plans. Radiation oncologists should also be carefully selected when selecting their team of radiation oncologists as this may significantly enhance treatment results. For these reasons it is vital that you select an experienced team.
Side Effects
Radiotherapy works to kill or slow the spread of cancer cells while simultaneously damaging healthy cells near them, leading to side effects like fatigue and loss of appetite for some individuals more than others. Symptoms depend on which part of the body receives radiation treatment as well as dose size and frequency of dose administration.
Your treatment will be carefully tailored so that the highest possible dose can be given directly to the cancer while causing minimal or no collateral damage to nearby healthy tissue, known as optimizing. Before beginning treatment, a CT scan will likely be conducted in order to pinpoint exactly where and how big the tumour is located; following which, you may be asked to lie still in a treatment room throughout each session; wearing either a plastic mask or mould, blocks, shields or protective barriers as needed (marked with permanent ink marks to assist therapist in targeting accurate).
Fatigue is a common side effect of radiation therapy that affects all patients. It may develop gradually or suddenly and last for months or even years before being managed with rest and exercise.
Radiation therapy to the neck or head may cause changes to your lymphatic system that result in lymphoedema – the build up of fluid (usually improving after treatment is complete, though this could become long term condition).
Radiation exposure can also alter blood cells, particularly white blood cells. This could potentially lead to infection or bleeding in an organism.
People receiving radiation to their head or neck may develop dry mouth and throat (xerostomia), or an inadequate sweat production in their armpits (axillary hyperhidrosis). This can make swallowing food difficult or cause appetite loss entirely; nutritionist may be recommended.
Some patients who undergo radiotherapy to the breast or lung may experience brachial plexopathy due to radiation affecting nerves that control muscles in their arms and hands. It’s more likely to happen with 3DCRT than stereotactic ablative radiotherapy treatments; however it could still happen with other forms of radiation therapy too.
