SBRT, also known as stereotactic ablative radiotherapy or stereotactic ablative body radiation (SABR), precisely targets tumours with high doses of radiation. The treatment is used for small tumours. The most common types of primary tumours are prostate cancer, lung cancer, and kidney cancer.
SBRT can also treat tumours that have spread or metastasised from another site. Patients with the oligometastatic disease have just a few metastatic spots. SBRT may be able to stop the spread of metastatic disease in these situations.
SBRT may be preferred over surgery in some cases. This avoids the need for a hospital stay, recovery time, and other aspects of a surgical procedure. It may also be an option for those not in good health to undergo surgery.
Fatigue is a common side effect of SBRT. There may be other side effects depending on where the tumour is located. An abdominal tumour patient may experience gastrointestinal problems as a result of SBRT. Bone damage can occur when a tumour is located near a bone.
In SBRT, several radiation beams of various intensities are directed at the tumour from multiple angles.
Treatment planning may require one or more sessions. In these sessions, the patient will undergo a CT scan, an MRI scan, and other advanced imaging techniques. Doctors use these images to map the location and shape of tumours accurately. To determine beam angles and intensities, they create a customised treatment plan.
A time-lapse video of the patient's breathing may also be taken if the tumour is in or near the lungs. The doctor will use the video to determine how motion will be incorporated into the treatment plan. While the video is being created during treatment, patients may be asked to hold their breath for short periods.
Additionally, the care team will create a mould of the patient's body near the tumour site. The mould is designed to place the patient in the most effective position for treatment. It also maintains the patient's position during treatment, ensuring that the tumour receives the full dose of radiation while surrounding healthy tissues are spared.
Patients undergo between one and five SBRT sessions following the planning process. It is either once a day or once every other day. The average session lasts approximately one hour.