Stereotactic Body Radiation Therapy (SBRT)

Stereotactic body radiation therapy (SBRT) is a type of radiation therapy that uses precise and focused high doses of radiation to treat small, well-defined tumors outside the brain.

Definition and Purpose

SBRT is also known as stereotactic ablative radiotherapy (SABR). It is designed to deliver high doses of radiation to small tumors in a few fractions, while minimizing damage to surrounding healthy tissues. The goal of SBRT is to achieve tumor control and minimize side effects.

Technique

SBRT uses advanced imaging technologies, such as computed tomography (CT), magnetic resonance imaging (MRI), and positron emission tomography (PET), to accurately locate the tumor and surrounding tissues. The radiation beams are shaped to match the size and shape of the tumor, allowing for precise delivery of high doses of radiation.

The SBRT process typically involves:

• Simulation: The patient undergoes imaging studies to determine the location and size of the tumor.
• Planning: A team of radiation oncologists, physicists, and dosimetrists create a personalized treatment plan using specialized software.
• Treatment delivery: The patient is positioned on a treatment table, and the radiation beams are delivered using a linear accelerator or other radiation therapy equipment.

Indications

SBRT is commonly used to treat various types of cancer, including:

• Lung cancer: SBRT is often used to treat early-stage non-small cell lung cancer (NSCLC) and small cell lung cancer.
• Liver cancer: SBRT can be used to treat primary liver cancer and metastatic liver disease.
• Prostate cancer: SBRT is sometimes used as an alternative to traditional radiation therapy for low- and intermediate-risk prostate cancer.
• Pancreatic cancer: SBRT may be used to treat locally advanced pancreatic cancer.
• Spinal tumors: SBRT can be used to treat spinal metastases and primary spinal tumors.

Benefits

The benefits of SBRT include:

• High tumor control rates: SBRT has been shown to achieve high local control rates for various types of cancer.
• Minimally invasive: SBRT is a non-surgical procedure, which reduces the risk of complications and recovery time.
• Short treatment course: SBRT typically involves only a few fractions, which can be completed in one to two weeks.
• Reduced side effects: The precise delivery of radiation minimizes damage to surrounding healthy tissues, reducing the risk of side effects.

Risks and Side Effects

While SBRT is generally well-tolerated, potential risks and side effects include:

• Fatigue: Patients may experience fatigue during or after treatment.
• Skin reactions: Skin irritation, redness, or dryness may occur in the treated area.
• Gastrointestinal symptoms: Nausea, vomiting, diarrhea, or abdominal pain may occur, especially when treating abdominal tumors.
• Respiratory symptoms: Coughing, shortness of breath, or chest pain may occur when treating lung or thoracic tumors.

Follow-up and Monitoring

After SBRT, patients typically undergo regular follow-up appointments with their radiation oncologist to monitor the response to treatment and manage any potential side effects. Imaging studies, such as CT or MRI scans, may be used to assess tumor response and detect any signs of recurrence.