“TomoTherapy is basically another linear accelerator, it’s just packaged a little bit differently,” says Dr. James Richardson. Acquired to complement Turville Bay’s Varian TrueBeam linear accelerator, TomoTherapy is proving useful in treating certain cancers. Tomo offers “ flexibility in our ability to treat various tumors and some of the constraints that we run into with patients with their body habitus or hardware in the body.”
The TomoTherapy treatment delivery system uniquely delivers radiation therapy in a spiral pattern (TomoHelical) or discrete-angle approach. Designed inherently for Intensity Modulated Radiation Therapy (IMRT), photon radiation is produced by a linear accelerator that travels around the patient. It moves in unison with a multi-leaf collimator that shapes the beam into beamlets, all aimed at the tumor. Typically, tens of thousands of beamlets are used in a single TomoTherapy treatment session. Software optimizes the contribution of each one to the total tumor dose, minimizing exposure to healthy tissue. Meanwhile, the couch is moving—guiding the patient slowly through the center of the ring. Treatments can be delivered continuously, from all angles around the patient. More beam directions give physicians more control in how they plan treatments—and assurance that dose will be confined to the tumor, reducing the risk of short- and long-term side effects.
Patient times are consistent with TrueBeam and TomoTherapy also offers onboard imaging, as Turville Bay physicians find more frequent CT scanning important with certain tumors.