Volumetric Modulated Arc Therapy in South Africa

What is Volumetric Modulated Arc Therapy?

Volumetric modulated arc therapy is new technology introduced in 2007 that delivers treatment with accuracy and speed. It is a novel radiation technique, which can achieve highly dose distributions with accurate target volume hence reducing the risks to normal tissues. The volumetric modulated arc therapy has the potential to reduce treatment delivery time when compared to the intensity modulated radiotherapy.

The volumetric modulated arc therapy can deliver the entire dose to the tumor in a 360-degree rotation in a small amount of time. It uses special computer software and an advanced linear accelerator to deliver the treatment much faster than previously possible. It incorporates the use of an algorithm that ensures treatment is done with precision to spare the health tissue surrounding that area.

Currently, there are several volumetric modulated arc therapy systems all with different names. They include:

• Rapidarc radiotherapy technology
• Varian
• SmartArc
• Elekta volumetric modulated arc therapy

Advantages of the volumetric modulated arc therapy

• Better dose distributions than the intensity modulated radiotherapy (IMRT)
• Has a high speed and accurate delivery of dose to the cancerous tumors hence decreased treatment time
• Potential for improved optimization due to increased number of beam directions
• The VMAT leads to increase monitor unit (MU) hence treatment is faster
• Minimizes exposure to the surrounding healthy tissues
• Its delivery system enables oncologists to treat tumors adjacent to critical body structures

How the Volumetric modulated arc therapy works

• Radiation is delivered only to the affected area. This is accomplished by the radiation machine which rotates around the affected area of the patient and delivering focused beams of radiation. The intensity and of the beam changes as the machine rotates
• 3D imaging is used to ensure accuracy of the procedure and also to allow the radiation specialist to determine the tumor position and formulate the right treatment plan.
• Sophisticated monitoring tools are used to enhance precision by monitoring the patient in real time to ensure precise delivery of the dose.
• During the Volumetric modulated arc therapy treatment the machine rotates delivering accurate beams of radiation to the cancer

Treatment planning

A team of radiation specialists and oncologists plan accurately the dose of radiation that better suits the patient. They decide on how many radiation beams to use and the angles they will be delivered from to ensure the complete eradication of the cancer.

Once the team is done with the initial planning, they calculate the dosage to be administered to that area and the treatment begins.

Which cancers does the volumetric modulated arc therapy treat?

This technique is used in treatment of cancers such as:

• Liver Cancer
• Prostate Cancer
• Pancreatic Cancer
• Gynecological cancer
• Head and neck cancer

Side effects of the Volumetric modulated arc therapy technique

The Volumetric modulated arc therapy technique has very little exposure to the normal tissue hence the possibility of side effects are low. However, possibility of side effects is still possible. The side effects may include:

• Tiredness
• Skin irritation