Stereotactic Radiotherapy (SRT)
What is Stereotactic Radiotherapy?
Stereotactic body radiotherapy (SBRT) gives radiotherapy to many different parts around the body. The beams meet at the tumour, so the tumour receives a high dose of radiation and the tissues around it only receive a low dose; this lowers the risk of side-effects.
Patients receiving SRT usually have between 1 to 8 treatments. SRT is also sometimes called Stereotactic Ablative Radiotherapy (SABR). When used to treat brain tumours, SRT is referred to as Stereotactic Radiosurgery (SRS).
Which cancers are treated with Stereotactic Radiotherapy?
This type of radiotherapy is mainly used to treat very small cancers, including:
- Brain metastasis
- Bone metastasis
- Vertebral bone metastasis
- Cancer of the Lung or cancer that has spread to the lung
- Cancer that started in the liver or cancer that has spread to the liver
- Cancers in the lymph nodes
- Spinal cord tumours
At the Cancer Centre London, we use an Elekta VersaHD linear accelerator which has the required precision and speed necessary to deliver advanced Stereotactic Body Radiotherapy (SBRT) & Stereotactic Radiosurgery (SRS).
Volumetric Arc Therapy (VMAT) treatment techniques are used to deliver SRT and SRS.
The Elekta VersaHD has a six degrees of freedom (6OD) hexapod couch that allows rotational and planar set-up
corrections. This ensures highly accurate treatment delivery. We immobilise our SRS patients with a bespoke double shell positioning beam directional mask. Audits have shown that this immobilises our patients to the highest exactness.
All SBRT patients are immobilised using the dedicated Eamis Lite body stereotactic kit.This permits stability during treatment delivery and minimises motion that results from respiration. All lung and treatment sites affected by respiration are planned using 4D CT.
Case reviews using pre and post PET scans of lung and brain patients treated at CCL have shown total tumour ablation with minimal side effects.