Fractionated Stereotactic Radiotherapy

Many tumours (both in the brain and in other organs) cannot be surgically cured. This is why, in certain cases, radiation therapy is required. Israeli clinics apply the most advanced XRT techniques to help patients recover as quickly as possible. One of these methods is fractionated stereotactic radiotherapy.

What is Fractional Stereotactic Radiotherapy?

FSR is a treatment method based on locating the exact position of the tumour and then delivering radiation to it. Therapy is split into several sessions performed over the course of several days. The exact number of procedures is determined by the tumour’s type, size and proximity to surrounding tissues.

FSR is delivered by “multiple fixed beams” using a mini-multileaf collimator or IMRT (intensity modulated radiotherapy), which is used to treat irregularly-shaped tumours. The beams are focused on a specific area, thus minimizing irradiation of surrounding healthy tissues.

When is FSR Indicated?

Fractional stereotactic radiotherapy is indicated in cases when a tumour cannot be surgically removed. Chief reasons for this include:

• Close proximity of the tumour to important brain structures (for example brain stem, pituitary gland or optic chiasm)
• Spinal cord involvement
• Status post previous treatment

It should be noted that patients with both benevolent (i.e. pituitary tumours, hemangiomas, meningiomas and schwannomas) and malignant brain tumours (i.e. gliomas or medulloblastomas) may benefit from FSR.

Treatment Process

Dosage is dependent on tumour’s proximity to important brain structures. Usually, treatments starts with a low dose of radiation delivered over several fractions throughout a day. The entire course is spread over the course of several weeks. Each treatment session lasts about 15-20 minutes. Common side effects include fatigue, alopecia and discomfort around the oral cavity (related to the dental plate used during treatments). These quickly resolve once the treatment is finished. Acute side effects are rare.

Simulation

Simulation is performed within 1 or 2 weeks of the commencement of the treatment and takes a few hours to complete. It includes:

• Taking an impression of the occipital part of your head and your upper palate
• Fitting of a specialized head-frame
• Attachment of impression molds to the base head ring
• CT scan

You should not undergo any dental treatment starting from the day of the simulation and until the treatment is finished. It is also not advised to change your hairstyle as it may affect the stability of the head frame.

Radiation therapy

Normally radiation therapy begins approximately a week following simulation. The head frame will be fitted before each treatment session. Periodical follow-ups with your oncological radiologist will take place to monitor your condition.

In Israel fractionated stereotactic radiotherapy takes place at Assuta Medical Center’s Dept. of Oncology.