Thinking of Proton Therapy?
Here is a quick proton therapy systems comparison guide.
Proton therapy has been growing in popularity due to its unique characteristics vs. conventional, external beam, MV (photon) radiation therapy. Proton’s unique feature is that the radiation beam “stops” at the tumor site, which translates to minimal damage to healthy tissue along the exit path of the beam of radiation. This is especially beneficial for children undergoing radiation therapy, since radiation exposure can often lead to secondary cancers decades later. Also, the “pencil beam” nature of the proton beam makes it a useful tool for tumors in sensitive areas like the eye.
For many private insurance payers, proton treatments are still considered experimental and approvals for coverage are often difficult to secure. This has made it difficult for owners of proton therapy centers to cover expenses, and several have gone bankrupt in recent years. However, a recent court case awarded millions in damages to a family of an individual that was denied coverage for proton therapy, so we may expect to see changes in the future.
There are two main types of proton machines: multi-gantry and single-gantry. Multi-gantry systems use one large cyclotron to generate beam that can be delivered to several different rooms at a time, allowing multiple patient treatments during the course of a treatment cycle. Single gantry models have only one gantry, and can treat only one patient at a time.
Because of the high cost of multi-gantry proton systems (often north of $300 million), they are usually installed only in large hospitals and university systems. However, single gantry units are much more affordable (if you believe $30 million is affordable). The first ever private cancer center to install a proton machine was the Ackerman Cancer Center in Jacksonville, Florida.
|Model||Discovery CT750 HD||LightSpeed VCT||LightSpeed VCT Select||LightSpeed RT16||BrightSpeed Elite||BrightSpeed Elite Select|
|Detectors, type||Gemstone scintillator||HiLight ceramic v-res||HiLight ceramic matrix 3||HiLight ceramic matrix II||HiLight ceramic matrix II||HiLight ceramic matrix II|
|No. of rows||64||64||64||24||24||24|
|Gantry dimensions, H x W x D, cm||188.2 x 222.5 x 100.6||188.2 x 222.5 x 100.6||188.2 x 222.5 x 100.6||189 x 223 x 101||193 x 206 x 102||193 x 204 x 102|
|Gantry weight, kg||1850||1995||1995||1920||1770||1770|
|Gantry aperture, cm||70||70||70||80||70||70|
|Heat storage, HU||8,000,000||8,000,000||8,000,000||8,000,000||6,300,000||6,300,000|
|kW output||100||72, 85 or 100||100||100||53.2||42|
|mA Range||10 to 835||10 to 600, 700 or 800||10 to 800||10 to 800||10 to 440||10 to 350|
|Max scan volume, cm||170 (200 option)||170 (200 option)||170 (200 option)||170 (200 option)||170||140|
|Max load capacity with accuracy, kg||227 +/- 0.25 mm||227 +/- 0.25 mm||227 +/- 0.25 mm||650 lb or 500 lb +/- 0.25 mm||227 +/- 0.25 mm||205 +/- 1 mm|
|Scan FOVs, cm||25, 50||25, 50||25, 50||10 to 50||25, 50||25, 50|
|Reconstruction matrices||512 x 512||512 x 512||512 x 512||512 x 512||512 x 512||512 x 512|
|Suggested room size (m2)||34.2 (21.7 min.)||34.2 (21.7 min.)||34.2 (21.7 min.)||28 (45 optimal)||18.2||18.2|