Radiation Oncology

The Department of Radiation Oncology at Narayana Health’s group hospitals provides patient-centric, state-of-the-art Radiotherapy treatment of international standards. Narayana Health is equipped with a wide spectrum of conventional as well as high precision Radiation Oncology facilities and radiotherapy techniques such as-
IGRT
IMRT
SRS
SRT
VMAT
Brachytherapy
Features:
High-quality, experienced, compassionate multidisciplinary care.
Personalized treatment plans that consider our patient’s health, age, cancer type and ability to tolerate potential side effects.
Leading-edge technology that delivers radiation with maximum precision, reducing treatment time.
Radiation therapy – overview
Radiation therapy is a cancer treatment that uses high energy beams to kill cancer cells. X-rays, proton beams, and other forms of energy are used in this treatment. A trained radiation oncologist would administer this treatment.
The problem with cancer is that it spreads fast and it spreads across the body affecting various organs. When radiation is directed on the cancer cells, it breaks the DNA inside the cell. This ensures the cell does not grow and divide, as a result, the cancer cell dies. It must be noted that radiation cannot distinguish between healthy and cancerous cells. All cells in the area targeted would die. This is the reason why cancer treatments like radiotherapy and chemotherapy cause side effects. Healthy cells would grow again, whereas cancer cells are unlikely to grow back.
Radiation therapy is a targeted treatment. While chemotherapy uses drugs that can expose the entire body to side effects, radiotherapy is focused only on a particular area. This minimizes death of healthy cells and reduces side effects.
Almost 50% of all cancer patients would need radiation therapy to treat cancer. It can be given along with chemotherapy. When cancer cells cannot be removed completely through surgery, radiation therapy is also used. The decision on using this treatment is taken by the treating oncologist along with the radiation oncologist. It’s decided based on the extent of cancer, type of cancer, and the overall health of the patient.
One more issue to note is that radiation therapy cannot reach all parts of the body. Its goals may not be to destroy all cancer cells, but to reduce the size of cancer cells, when the tumor has grown large. This helps remove the reduced tumor during surgery. In some cases, radiation is used after surgery to ensure cancer cells do not grow back.
Types
There are two types of radiation therapy. They are:
1.External beam radiation:
As the name suggests, here the radiation beams are directed externally, i.e, from a source outside the body. The equipment used to deliver the radiation will be directed at the target area (that is decided by the radiation oncologist in advance). The area to be targeted, the type of radiation to be used, and the extent of radiation are decided based on the individual case history. Some of the equipment used for external beam radiation are:
X-ray machines.
Proton beam machines.
Cobalt-60 machines.
Neutron beam machines.
Linear accelerator.
Gamma knife.
External radiation is painless. It is usually an outpatient treatment and the patient can leave once the session is complete. Multiple sessions would be needed to complete treatment.
The radiation used may be high energy, if the cancer cells are deep. When cancer cells are located on the surface, then low energy beams are used. This kind of an application of radiotherapy needs expertise, which is why a radiation oncologist supervises the entire process.
A form of external beam radiation is stereotactic therapy. This works on the principle of using a very high beam of energy that is focused on a very small area on the body. It also involves targeting a tumor from multiple angles. The advantage of this therapy is that the tumor is completely targeted from all sides in a concentrated way. This ensures the tumor is destroyed. At the same time, it avoids targeting healthy cells and thus minimizes the side effects of radiotherapy.
The gamma knife is a tool used in external radiation therapy. It can be used to treat brain tumors without making any surgical incision. It uses Cobalt-60 radiation that delivers targeted radiation of the affected cells to destroy it. No healthy cells are damaged.
2.Internal Radiation Therapy:
This is also known as brachytherapy. Unlike external therapy, radiation is not delivered in the form of beams. Instead, the radiation source is placed internally near the tumor where it delivers radiation at close range and destroys the tumor. It is very helpful in treating cancers of the neck, cervix, vagina, eye, and rectum. Wires that are radioactive may be placed inside the body using the applicator. This would ensure the affected area gets radiation internally to destroy cancer cells.
The applicator is a metal or plastic device inserted internally and is suitable for use in body cavities. The applicator is left in the body until the treatment is complete, after which the radiation oncologist removes it from the body. Internal radiation may also be delivered through intravenous mode. Small molecules would have radioactive particles attached to it and these are delivered intravenously. When internal radiation is used, the oncologist needs to monitor the patient regularly to find out if any radioactive particles are remaining after completion of treatment.
The Process Behind Radiation Oncology
Radiation oncology is administered by a team of trained professionals under the supervision of a radiation oncologist. The oncologist is a doctor who is overall in-charge of managing the treatment. The doctor decides on the type of radiation therapy to be used, dosage, and other such parameters. The radiation physicist is a technician who actually operates the equipment and delivers radiation to the patient.
A dosimetrist is the person responsible for calculating the dosage of radiation and monitoring it to ensure the right dose is given. The radiation therapist helps the patient through the therapy ensuring the patient is in the right position to receive radiation. A nurse would also be available for assisting the doctor. Radiation oncology also uses the assistance of a dietitian to help the patient plan a healthy diet during and after treatment.
There are different types of radiation. The type used in radiation oncology is known as ionizing radiation. This is because the radiation forms ions, or charged particles in the cells, in which it enters. These ions would be formed by taking out electrons from atoms. This causes changes in the DNA and kills the cells. From these ionizing radiations, x-rays and gamma rays are called photon radiation. When electrons, protons, beta particles, or carbon ions are used, the radiation is called particle radiation. The type of radiation depends on the cancer type and stage.