What is Radiotherapy?
Radiotherapy (radiation therapy) is a treatment method that uses high doses of radiation to kill cancer cells in a specific area or to shrink a malignant tumour. Radiation damages the DNA of the cell, preventing cancer cells from dividing and eventually leading to their death.
Radiotherapy can be administered alone or in combination with chemotherapy, immunotherapy, cancer surgery or hormone therapy.
The aim is to eliminate the cancer, shrink the tumour or, in the early stages of the disease, completely eradicate the cancer by delivering high doses of radiation to the cancerous area.
Radiotherapy is divided into two types according to the method of application: internal and external.
External radiotherapy is a method of delivering high doses of radiation to the cancerous area superficially. When radiotherapy is mentioned, it is usually the external radiotherapy method that comes to mind.
The duration or number of radiotherapy sessions varies depending on the stage of the disease, the patient's general health, and the location of the cancer. Radiotherapy is generally a painless method, but its side effects vary depending on the area and dose.
How is Radiotherapy Performed?
Radiotherapy is administered regionally by targeting cancerous tissues using devices called linear accelerators, which produce high-energy radiation. Radiotherapists and dosimetry teams define the target volumes and organs at risk and adjust the dose distribution. Each session is called a ‘fraction’. The total duration and number of sessions of radiotherapy vary depending on the cancer. Radiotherapy is performed as follows:
Is Preparation Required Before Radiotherapy?
There are simulation and planning stages before radiotherapy. The radiotherapy team determines the patient's treatment position, dose distribution, and organs to be protected. Before radiotherapy, the patient must stop using tobacco and alcohol, pay attention to their diet, stay hydrated, and manage fatigue. If radiation is to be administered to the mouth and throat area, a dental evaluation and oral care plan may be required. In pelvic radiotherapy, specific preparation may be necessary for bladder fullness and bowel movements.
Who Receives Radiotherapy?
Most patients diagnosed with cancer receive radiotherapy at some stage of their treatment. The radiotherapy dose intensity, number of sessions, and duration vary depending on the stage of cancer, the patient's general health, and the location of the cancer.
What are the Purposes of Radiotherapy?
Radiotherapy is administered for curative, adjuvant, neoadjuvant, or palliative purposes, as follows:
Curative radiotherapy
The goal is to completely eliminate the disease. It is generally preferred for early-stage cancers. It can be administered alone or in combination with chemotherapy.
Adjuvant radiotherapy
This is radiotherapy administered after surgery to eliminate any microscopic tumours that may remain after the tumour has been removed or the cancerous cells have been cleared during surgery.
Neoadjuvant radiotherapy
This is radiotherapy administered before cancer surgery. It is used to shrink the cancerous area, facilitate the surgical procedure, or increase the chances of success.
Palliative radiotherapy
This is radiotherapy administered not to treat the cancer but to alleviate the symptoms experienced by the patient. The aim is to reduce complaints such as pain, bleeding, and shortness of breath.
Tomotherapy
Tomotherapy is a radiation therapy that combines computed tomography technology with radiotherapy, offering 360-degree rotation and precise targeting. The patient lies on the tomotherapy machine, and imaging, targeting, and application are completed in a single device.
It is the only radiotherapy system designed on the basis of a Computed Tomography (CT) scanner. The system often resembles a CT scanner when viewed from a distance because it is one. This allows your entire treatment, including daily 3D imaging and 3D treatment, to be completed on a single system.
Radiation Oncology