External Radiotherapy Unit
About
External beam radiotherapy (EBRT) is a treatment method used for delivering high energy radiation to tumour so the cancer cells are destroved while sparing the surrounding normal tissue.
The treatment is done using a machine called linear accelerator (LINAC). High-energy x-rays or electrons are produced by the LINAC and directed to the target with precision from various angles.
Multi leaf collimators (MLCs) are made of thin lead leaves that move while the machine moves around the patient. The MLCs form shapes that fit precisely the target.
A team of radiation oncologist, medical physicist, dosimetrist and radiation therapist are working together to produce a highly refined plan and achieve high quality treatment. The planning of your treatment may take several days and there is usually a week delay between planning appointment and your first treatment appointment.
External Radiotherapy is carried out in special radioactive-protected rooms where high-energy X-Rays are aimed at the tumor using a machine called linear accelerator. Find more about our equipment here.
External Radiotherapy Techniques
A series of images are produced prior treatment to assure that patient’s position is exactly as it was at the time of the CT scan. This is done using a kV CT scanner attached to the LINAC that obtains real-time 3D images of the patient (called cone beam CT). Thus, IGRT aids the accuracy of beam direction since beam positioning can be checked and verified prior treatment delivery.
A 3D conformal radiation treatment shapes the radiation beams to closely fit the area of interest. This allows the exact targeting of the tumour and the delivery of minimal dose to the surrounding normal tissue.
IMRT is a type of conformal radiotherapy, which is used to treat complex treatment volumes. The basis of this technique is the use of intensity modulated beams that can provide various intensity levels of radiation. Thus, different doses of radiation are delivered across the tumour. This technique is planned using inverse planning algorithms; ensuring conformity and dose homogeneity to the tumor while spearing close proximity organs at risk.
This is an advanced type of IMRT. The machine rotates around the patient during radiotherapy in an arc shape and continuously reshapes and changes the intensity of the radiation beam as it moves, enabling faster treatment delivery.
It is a highly precise technique for the irradiation of tumors. This technique uses advanced imaging and computerized systems to pinpoint the tumor’s exact location, enabling treatment to be delivered over fewer sessions than conventional radiotherapy. When administered in a single fraction, the exceptional accuracy of dose delivery in stereotactic radiotherapy resembles the precision of a surgical scalpel, which is why this technique is also known as radiosurgery.
Stereotactic radiotherapy can be applied to a variety of tumors, primarily to those that are small and well-defined. It is commonly used for intracranial metastases and benign brain tumors, early lung cancer, prostate cancer, liver cancer, spinal tumors, kidney cancer, pancreatic cancer and in the oligometastastic disease, where the cancer has spread to a limited number of distant sites.
Our Department possesses extensive experience and provides a comprehensive range of stereotactic radiotherapy services. This expertise has led to our designation as a reference center for stereotactic radiotherapy by Elekta, a leading provider in the field.
