(PR.co.nz) Patients with prostate cancer typically are required to lie still for seven to eight minutes with a full bladder during a therapy session, a process repeated 37 times over a treatment course. However, for clinicians at St. George’s Cancer Care Centre in Christchurch, New Zealand, providing “typical” prostate cancer therapy wouldn’t do. They acquired Elekta technology that enables them to deliver prostate therapy in half the per session time, improving patient comfort. In December, only nine months after opening, St. George’s used Elekta VMAT for the first time to treat a 67-year-old patient with prostate cancer.
“We used a single non-stop arc of the radiation beam and just under three minutes of actual therapy time,” notes David McKay, Principal Physicist at St. George’s located on New Zealand’s South Island and the second center in Australasia to use Elekta VMAT. He is about three-quarters of the way through his treatment course and is doing very well.”
The arc-based technique was part of a comprehensive acquisition of Elekta technology by St. George’s, which also included two Elekta Synergy® linear accelerators, Monaco® treatment planning for Elekta VMAT and MOSAIQ® oncology information system. Together, these products represented a complete VMAT solution for St. George’s, McKay maintains.
“We wanted to offer the best possible treatment to our patients by using the most advanced technology available,” he says. “Elekta offered a full package that included the planning system, record-and-verify system and the linear accelerator. It was very appealing that we could get all that from one provider. It helps if the planning system and accelerator come from the same vendor – so that technology improvements in the linac are then reflected in the planning system more quickly. The communication between MOSAIQ and the treatment planning and therapy systems also is critical to streamline information flow.”
Since its first patient, St. George’s has started its second prostate cancer patient on Elekta VMAT therapy. For both patients, VMAT planned with Monaco has been successful, McKay observes.
“The plans compare favorably with our IMRT plans, and using Monaco planning for the second patient, we developed a plan that shifted the radiation dose somewhat better around the rectum, which helped us avoid exposing it to an above-tolerance dose. The doctors were very pleased with that,” he says. “Additionally, the Monte Carlo dose algorithm improves our ability to calculate the final patient dose, which helps us deliver the highest therapeutic dose confidently.”
With its Elekta Synergy acquisition, St. George’s also received Symmetry™ respiratory motion management. Revolutionizing the process of visualizing moving tumors during lung cancer treatment, Symmetry enables clinicians to reduce margins, account for baseline shifts and employ uninterrupted treatment delivery while the patient breathes freely.
Anticipating a greater volume of patients with lung cancer at the clinic, a team of clinicians, physicists and radiation therapists at St. George’s has begun evaluating the 4D imaging capabilities of Symmetry in select lung cancer patients.
“In a recent case, the radiation oncologist had created some standard margins around a tumor of a lung cancer patient scheduled for palliative treatment,” McKay recalls. “We did a scan to observe the tumor motion and confirm the margins were satisfactory. We were quite surprised at how much movement the 4D acquisition revealed in this case. The margins were just about adequate to cover the volume, but if there had been just a little bit more movement we would have had to replan the case. It was eye-opening. The 4D capability is a useful feature that will help ensure the highest standard of care for our patients.”
Elekta VMAT and Symmetry will be discussed in detail at the 2011 Elekta User Meeting in Sydney. Learn more at www.elekta.com.au.
*Approval of indications may vary between different countries and additional regulatory clearances may be required in some markets.
Media Release 25 February 2011.