IMRT greatly improves the ability of the oncologist to deliver the optimal dose of radiation to the tumour by accurately sculpting the shape of the radiation beam. This technology now ensures that normal tissue can be spared which is particularly important in cases where a tumour is located close to delicate or essential organs. When normal tissue can be spared, a higher radiation dose can be delivered to the tumour, thus increasing the chance of destroying the cancerous cells.
The clinical team at Edmonton's Cross Cancer Institute, Alberta, Canada, treated a naso-pharynx tumour, sparing the parotid gland, by applying the "step and shoot" technique and a 52 leaf multi leaf collimator (MLC). The patient who was treated had a tumour which was very close to the salivary glands. Utilising traditional radiation treatment would have normally resulted in unpleasant side effects such as dry mouth and difficulty speaking and swallowing. Using IMRT, it is possible that these side effects will be minimised.
"This is a major milestone", stated Ken Johnson, MDS Nordion's Senior Vice-President, Therapy Systems. "We are among the leaders in bringing the benefits of this novel technology to patients around the world. Using Helax-TMS treatment planning software, the cancer centres are able to offer the best possible cancer care." Mr. Ken Johnson added that he is particularly pleased to have customers utilising both Siemens and Varian linear accelerators which deliver IMRT treatments with Helax-TMS inverse planning. "This demonstrates MDS Nordion's ongoing commitment to provide its customers with open solutions allowing the flexibility to use our software with different vendors' equipment."
The Helax-TMS version 5.X includes an optimisation tool, which allows the physician to specify the dose-volume constraints to targets and critical structures. These are then used to optimise the dose distribution. The tool can be used to create plans intended for Segmented IMRT treatment delivery, IMRT delivery using compensators or just simply beam weighting and wedge angle. Colin Fields of the Cross Cancer Institute commented, "One of the nice aspects about the Helax-TMS IMRT option is how a treatment as complex as IMRT can be easily planned by the staff at our clinic. We are very lucky to have this powerful software tool that enables us to offer our patients the most effective way of treating many types of solid tumours."
The software's inverse planning algorithm includes a complete calculation, including headscatter in each iteration. The entire optimisation, calculation, and sequencing routine occur as a background calculation enabling ongoing planning with the treatment planning system. Helax-TMS has been designed to make it easy to prepare and compare cancer treatment plans both with and without inverse planning. A fully informed clinical decision can then be taken regarding which treatment plan to use.
The Helax-TMS IMRT solution includes a completely integrated sequencer which provides the choice of either sending the individual field segments or sending the intensity map to the target treatment unit. MDS Nordion's flexible, open approach means that Helax-TMS has been developed for use with different treatment delivery systems. For example, Elekta, Siemens and Varian linear accelerators can deliver IMRT treatments planned on Helax-TMS. Clinical work with Helax-TMS software is underway in Valencia Eresa, Spain, which is expected to be the second site to complete a patient's cancer treatment using Helax-TMS. Throughout the world, forty-eight other MDS Nordion customers will begin performing IMRT treatments once the quality assurance testing is complete at each site.
MDS Nordion specialises in radioisotopes, radiation, and related technologies applied to diagnose, prevent and treat disease. MDS Nordion is part of MDS Inc., an international health and life sciences company based in Canada. The company's 11.000 employees are working together to advance global health through science, technology and innovation. This is performed by providing laboratory testing, imaging agents for nuclear medicine testing, sterilisation systems for medical and consumer products, research services to speed the discovery and development of new drugs, therapy systems for planning and delivery of cancer treatment, analytical instruments to assist in the design of new drugs, and medical and surgical supplies.