What is Radiation Therapy?
Radiation therapy is a common treatment for cancer that uses radiations like x-rays, gamma rays, protons or electron beams to destroy or control malignant cancer cells. The other names for it are radiotherapy, irradiation, x-ray therapy, or radiation oncology.
How does it act?
Cancer cells multiply and divide faster than normal cells. Radiation therapy is a localized treatment, which works by breaking the internal part of the DNA cells of a particular area. In this way, the radiation stifles the growth and the division of the malignant cells and often destroys them completely.
Only in a few rare cases the radiation is given in an entire vein or orally. In such treatment the radiation passes through the whole body to reach its target region. Sometimes the nearby normal cells are also affected by the radiation, so the treatment should be carried out under meticulous supervision.
What are different types of Radiation therapy?
Radiation therapy can be broadly divided into two categories:
- External Radiotherapy
- Internal Radiotherapy
External Radiotherapy: A patient undergoing external radiotherapy is given high energy radiation at the cancerous site by a machine, which is directed exactly to the treatable area. External radiotherapy is a course of treatment given over a span of few weeks. The treatment is painless and takes around 15 minutes. The external radiotherapy is of several types:
- Three-Dimensional Conformal Radiation Therapy (3D-CRT) – It is used to show the shape, size, and location of the tumour through MR, CT, or PET scans. The radiation beams are modified according to the size of the tumour and then given from several directions.
- Intensity Modulated Radiation Therapy (IMRT) – It is an advanced form of 3D-CRT, in which the beam’s intensity can be adjusted and the radiation is more properly shaped to fit the tumours size.
- IGRT – It uses image guided radiation therapy, because there is a chance of the tumour moving between treatments.
- Tomotherapy – In this, IMRT is combined with Computed Tomography scanning technology to create 3D images of the body’s interior.
- SRS – In SRS, superior image-guided technique is used to deliver an exact dose of radiation to a small tumour in the head and neck region.
- SBRT – In SBRT, the same technique as SRS is performed in the other parts such as the liver, lung, spine etc.
- Proton Therapy – In this proton beams are used to treat cancer.
Internal Radiotherapy: In Internal radiotherapy, also called Brachytherapy, a radioactive source or a needle is placed inside the body of the patient. The radioactive source can be solid as well as liquid. If a liquid source is used, it is often termed as radionuclide therapy. In this type, the patient’s movements are often restricted until the radioactivity has fully disappeared from his/her body.
What is the dose of Radiation Therapy?
The dose depends on two things:
- Type of Cancer
- Stage of Cancer
The other factors considered by the radiation oncologist are:
- If the patient is under Chemotherapy
- If it is administered before or after the surgery
- What is the degree of success of the surgery
Generally, in curative cases the dose of radiation on a solid epithelial tumor varies between 60-80 Gray while on lymphomas the amount of radiation varies between 20 to 40 Gray.
The dose is actually a part of the treatment planning and the oncologist prescribes the dose in a way that the dose concentrates mainly on the tumor and affects the surrounding healthy tissues the least.
Who will plan & decide my Radiation Therapy?
A team of highly trained medical professionals work in unison to plan and decide the radiation therapy.
Who all are parts of Radiation Oncology Team?
The team includes:
Radiation oncologist: He/she will be in charge of the entire therapy and plays the chief role in developing the patient’s treatment plan.
Radiation oncology nurse: He/she assists the radiation oncologist throughout the therapy, monitors the patient’s health 24*7 during treatment, gives valuable suggestions regarding how to control probable side effects and also offers support to you and your family.
Medical radiation physicist: He/she has a thorough knowledge of the radiation equipment and often helps the oncologist with complex treatment plans.
Dosimetrist: He/she is a person, who works with the medical radiation physicist and the oncologist to develop the complex treatment plans and prescribe the apt dose of radiation.
Radiation therapist: Also called radiation therapy technologist, his/her primary responsibility is to maintain the treatment machines and administer the scheduled treatments.
Other medical and health care professionals: Other professionals include general physicians, nutritionists, dentists, counsellors, physical therapists, and social workers.
What are the benefits of Radiation Therapy?
There are many benefits of Radiation Therapy:
- It can destroy cancer cells of almost all parts of the body. It not only treats cancer but also successfully eliminates the tumor in some cases to prevent recurrence.
- It shrinks the tumor before surgery and treats remaining cancer cells (if any) after surgery.
- Palliative radiation therapy (when the complete elimination of the tumor is not possible) increases life span, reduces pain and lessens other cancer symptoms considerably.
- It improves the overall results of treatments such as chemotherapy or other hormonal therapies if given simultaneously.
- According to most patients, the effect of this therapy is minimal on daily schedules.The patient needs not stay in the hospital during the course of the radiation therapy in most cases and the sessions are carried out on an outpatient basis.
What are the side effects of Radiation Therapy?
The side effects of radiation therapy might crop up within a few days or weeks of the treatment or might not show up still months. The side effects depend a lot on the area where the therapy is given. However there are some common side effects that are found in many patients:
Fatigue: The radiations while destroying the cancer cells often give rise to substances that lead to fatigue. Besides, fatigue is also caused by lower blood count, anaemia, malnutrition, pain, steroids, chemotherapy, some high dose drugs and depression. There is no specific treatment for fatigue. If it is caused due to lower blood count, blood transfusion might help. Moderate exercises and a happy and healthy lifestyle also lessen fatigue to a great extent.
Skin changes: The latest procedures of radiation therapy cause less skin damage but still a faint redness is generally noticed on the patient’s skin after the treatment. The skin gets overtly sensitive with some blistering of the outer layer. The skin may also get dry and itchy and the pigment may turn darker. The skin becomes thin gradually in some cases and sometimes wounds on the treated area take a lot of time to heal. Application of aloe vera, lanolin or Vitamin E helps but this should be done under proper supervision of the doctor. The patients can also use a hat and scurf while going outdoors. This will prevent the skin problems from getting aggravated.
Throat and mouth problems: Mucositis or inflammation inside the mouth and throat is another side effect of radiation therapy. It is a short term side effect and gets better with time. Mucositis makes swallowing difficult and patients tend to lose weight as they cannot eat properly. Other mouth problems include dry mouth, damaged salivary glands, thick saliva etc. The patients should always keep their mouth cleanduring the course of the therapy and also when it’s over. If the situation turns too critical and eating becomes really difficult, a feeding tube is connected with the patient’s stomach for enough supply of nutrition. Radiation often affects the teeth and a proper mouth care post therapy is extremely necessary. Patients should consult a dentist before going for the surgery, who can suggest precautionary measures beforehand.
What is the cost of Radiation Therapy?
The cost of the Radiation therapy varies from one oncology centre to another. If advanced equipment are used, the cost is likely to go up. The cost also depends on the number of scans required for the patient. Most health insurance plans cover it; however sometimes the patients need to pay for a few processes of the treatment.
It is always better to have a clear discussion with the hospital office regarding their policy and how the health plan can be implemented before starting the treatment. Unfortunately, the cost of Radiation is drastically going up currently making it difficult for patients belonging to a lower income group.
How are different types of Radiation Therapy given?
In the external radiotherapy the doctor first specifies the area that is to be treated. This comes under a process called simulation in which the radiation therapist uses a CT scan or an MRI machine to define the treatment field (or port). Radiation beams are aimed very specifically on the marked region. When the radiation is given, a leg mold or mask is used to keep the patient static in one position. The mark should not be removed as it is required until the treatment is over.
In case of internal radiation therapy, an implant is placed inside the tumor of the patient’s body. It is positioned in a way that it affects the normal cells as less as possible. In this type of surgery a higher dose of radiation is given to a smaller area, which is always not possible in external radiation therapy. In brachytherapy (the biological name for internal radiation therapy) two methods of radiation therapy are used:
- Intracavitary radiation: The implant is placed in a specific cavity of the body like rectum or uterus.
- Interstitial radiation: The implant is placed in the tumor itself or very close to the tumor. This type shows early results and is more commonly used.
Different kinds of implants are used in internal radiation therapy that include seeds, balloons, tubes, pellets, wires, needles, or capsules.
Do I need to get admitted for Radiation Therapy?
The patient undergoing external radiation therapy needs not stay in the hospital. It is generally given during outpatient visits. It also does not take much time; 15-30 minutes is enough for a session of external radiation therapy.
For internal radiation therapy the patient often stands a chance of emitting radioactivity which is detrimental to other people. So, he/she needs to stay in the hospital for a few days during the treatment till all the radioactive sources have completely disappeared.
How much time is required for Radiation Therapy?
It takes very little time. It requires 15 minutes to 30 minutes. Only in a few special cases it takes more than 30 minutes. A full course of treatment requires several weeks in some cases and in some other cases the treatment gets over just within a few days.
What steps will I have to follow to get Radiation Therapy?
It follows a number of steps.
First, the patient needs to have a consultation session with the radiation oncologist and his/her medical team. During this visit the doctor does a thorough physical examination of the patient, scrutinizes his/her medical history and discusses the feasible treatment options. After this session the doctor either gives a date on which the therapy will start or he/she may ask the patient to come for a follow up visit. The consultation session takes around 2 hours.
In maximum cases the consultation session is followed by a simulation appointment. The main purpose of the session is to map the exact area, where the radiation beams will be directed. Once the area is figured out, a CT scan is performed to verify the anatomical features of that particular area for assurance. If the scan report comes as expected, the area is dotted with permanent ink, which is not removed till the treatment is over. The radiation therapist will have a clear cut discussion with the patient regarding his/her treatment time and how many sessions he/she requires. The simulation appointment takes around 1 hour.
The radiation therapist generally schedules a date after two or three weeks of the simulation session. This is the time when the radiation oncologist create a proper treatment plan taking into account the patient’s physical condition, the present state of his/her tumor and his/her medical history. On the basis of these, the oncologist decides the type of radiation equipment that will be used for the surgery as well as the amount of radiation needed.
Once the plan is properly chalked out the radiation treatment starts. The treatment procedures vary from one cancer type to another and from one individual to another as well. Even a single patient might find a difference between his/her previous session and current session.
My Radiation Therapy is over. How should I follow up with my doctor now?
Once the entire course of treatment is completed, the radiation oncologist schedules some follow up visits. He/she needs to examine you at intervals to see if any side effects are cropping up and how those can be taken care of. Besides, he/she will give the patient a set instructions, that need to be strictly followed.