Volumetric modulated arc therapy (VMAT) is an advanced radiation therapy technique that works by delivering a continuous arc of radiation around your body, rather than individual beams typically used by other forms of radiation. As the machine (called a LINAC) moves, it automatically changes the beam shape and treatment dose.
At GenesisCare, we provide VMAT for a variety of cancer types at many of our centers.
VMAT is a more advanced form of intensity modulated radiation therapy (IMRT), which allows for accurate targeting of a tumor and reduces radiation exposure to surrounding tissues and organs. While all forms of IMRT are excellent at sparing healthy tissues, VMAT allows for a continuous dose of radiation to move around the body without stopping the machine to reshape the beam, and therefore is also delivered in a quicker timeframe.
As with all forms of IMRT, VMAT uses- image guided radiation therapy (IGRT) to monitor and target the area your radiation oncologist wants to treat. This can include x-rays, CT scan, MRI or other technologies to visualize the area of interest before and/or during treatment to enable precise targeting, improve outcomes and lower risks of side effects.
Because of the advanced technology, the benefits of VMAT include:
- Shorter treatment delivery time
- Precise and accurate targeting of tumors
- Minimal dose of radiation to surrounding healthy tissues and organs
- Typically fewer side effects than other radiation techniques
VMAT has the capability to treat a wide range of cancers, and is ideal for treating:
- Tumors close to critical organs
- Large tumors requiring a widefield approach
- Cancers on irregularly curved skin
At GenesisCare, we offer VMAT to treat:
Several factors contribute to whether VMAT is the right radiation therapy technique for you, including your cancer size, location and stage. Our radiation oncology team will work with you to create a personalized treatment plan, customized to your needs and goals, and advise if VMAT is an appropriate approach.
Prior to radiation therapy with VMAT, you will need to undergo a CT simulation. This simulation creates a detailed view of your cancer and surrounding organs to help with the planning process. Once your simulation is complete, your radiation plan will be customized, reviewed and approved by your radiation oncology team. Depending on your individual situation, you may need small permanent markings placed on your skin to help with targeting the radiation. You can also expect your team to create an immobilization device, such as a headboard or mold, which will help you remain in the same position and still during treatment.
Once your plan is complete, your treatment will begin. You will lie on the treatment table for each radiation session while the radiation beam moves around you. Typically, there is no pain associated with radiation delivery, and you should be able to return to your normal activities right after in most cases. The number of treatment sessions you need will vary based on your individual plan.
Will I be radioactive after a VMAT session?
No. VMAT does not make you radioactive and it is safe for you to be around other people, including children and pregnant women, throughout your treatment.
What clothing should I wear during treatment?
Whenever possible, we recommend you wear loose-fitting clothing to allow you to change easily for each session and to help reduce any skin irritation as treatment progresses.
What side effects can I expect?
Side effects vary depending upon the type of cancer you have and where the treatment is delivered. Since radiation therapy is a localized treatment, you can expect that your side effects will typically be within the area being treated. Your care team will advise you on what side effects you can expect and at what point they may arise during treatment. Typically, because of its precise targeting, the side effects are fewer and/or lessened with VMAT. Additionally, side effects typically resolve within a couple of weeks after treatment is complete.
Can I work during treatment with VMAT?
This depends on your individual situation. If you are currently working, you should be able to continue throughout your radiation therapy. While appointments are typically scheduled five days a week for several weeks, our teams will do their best to coordinate your treatments at times that work for you. Additionally, because of our extensive network, we offer many locations so you can receive treatment, close to home, or work.
Can I drive during treatment with VMAT?
In most cases, you should be able to drive and continue with your daily activities while undergoing radiation therapy. However, depending on where your radiation is delivered, you may experience fatigue as a side effect. If you are feeling tired, you should consider arranging transportation to and from treatment.