In the expansive region of Australasia—which includes Australia, New Zealand and neighboring islands—Auckland Radiation Oncology Centre (ARO) is the first to use Elekta VMAT , treating a patient with prostate cancer using a single 100-second arc of radiation. Such rapid treatments change the entire therapy experience for these patients, who have had to remain completely still for seven minutes during radiation delivery for each of 37 to 39 separate treatment sessions or “fractions.”

“When treating prostates, any internal organ motion or patient movement during the fraction is a problem,” says John Simpson, Ph.D. chief physicist at ARO, New Zealand’s first private radiation oncology center. “Some internal motion is inevitable, and patients are treated with a semi-full bladder at the start of treatment to push the colon upward and away from the radiation field to minimize its exposure. Prolonging treatment duration, therefore, both increases the probability of internal organ motion as well as external movement due to patient discomfort, both of which can hinder treatment accuracy. Adopting a technique that reduces treatment delivery time is an obvious benefit for these patients.”

Elekta VMAT was an ideal solution for ARO’s prostate cancer patients, who represent nearly one-third (approximately 20 patients) of the center’s daily treatment volume of 70 to 80 patients. Since June 7, when the first patient began receiving Elekta VMAT therapy on ARO’s Elekta Synergy® treatment system, eight additional patients have begun treatment courses and another two are awaiting therapy.

“Elekta VMAT is now our technique of choice for patients with prostate cancer,” says Dr. Simpson, who leads a team that compared the arc therapy technique with its advanced image guided Intensity Modulated Radiation Therapy (IMRT) method. ARO physicists subjected Elekta VMAT to extensive quality assurance testing to ensure both delivery and plan quality were comparable to IMRT. Currently, the complete prostate treatment session encompasses patient set-up, pre-treatment imaging and Elekta VMAT delivery (100 seconds) for a total of 20 minutes.

“We haven’t decreased the treatment slot yet because we want to gain confidence that we will have interruption-free delivery,” Dr. Simpson observes. “Once we have this confidence we can start to reduce the timeslots from 20 minutes to 15 minutes. Multiplied by 20 plus patients per day, we will gain an hour-and-a-half, which should help us add more timeslots to increase access to care.”

(L to R - Chief Physicist: Dr. John Simpson, CSci CRadP; Charge Radiation Therapist: Denise Redwood, BSc RT(T) and Clinical Director: Professor Chelleraj Benjamin, ONZM.)