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News from the booths: BrainLAB and Xoft
09.30 PDT Wednesday: I went along to a couple of neat product demonstrations in the exhibition hall yesterday. First up, David Brett of BrainLAB, the German IGRT vendor, took me for a test drive on the company’s iPlan RT treatment-planning software - specifically, iPlan RT Automatic Prostate Segmentation.
Traditional treatment-planning methods require a manual analysis of multiple CT scans of the prostate and surrounding organs, a process which is labour-intensive, time-consuming and often prone to questionable reproducibility. The iPlan software features a granular anatomical atlas which, when used as a template, can visualize each patient’s internal dimensions through a process called “elastic fusion”.
According to Brett, the BrainLAB software offers two big advantages versus standard manual contouring procedures. First, the time saved in critical steps, such as contouring tumours for accurate treatment outlines, enables more patients to be treated in a given timeframe. Second, the software enables clinicians to visualize risk structures with a much higher degree of consistency.
“The automatic segmentation tool can greatly enhance the overall efficiency of the contouring process [and] this leads to a reduction in the time required for contouring from an average of 30 minutes to five minutes per patient,” explains a clinical validation note from Charles Enke and colleagues in the department of radiation oncology at the University of Nebraska Medical Center (Omaha, NE).
Brett says more than 120 hospitals worldwide have purchased iPlan RT Automatic Segmentation software since it was originally launched at the ASTRO annual meeting in 2005.
Next I met with the folks at Xoft, the Fremont, CA manufacturer which is pioneering a miniaturized electronic brachytherapy technology. Xoft’s Axxent System is based around a 2.25 mm diameter X-ray source that delivers localized and targeted radiation treatment.
Unlike radionuclide-based brachytherapy sources, the radiation can be switched on and off as required. The lower energies involved remove the need for expensive shielding, while the lack of radioactive material eliminates the complex logistics associated with handling isotopes. As a result, Axxent is easier to deploy from a clinical perspective versus conventional approaches, giving doctors and patients better access to brachytherapy treatments.
Axxent’s first commercial application is accelerated partial-breast irradiation (APBI), for which Xoft received 510(k) clearance from the US FDA in December 2005. Currently, there are 10 clinical sites using the system in post-clearance to treat early-stage breast cancer.
“We’ve also got 510(k) pending for our next clinical indication - endometrial cancer - but I don’t want to put a timeframe on it right now,” noted Marga Ortigas-Wedekind, Xoft’s vice-president of marketing and development.
In APBI, which was being showcased on the booth, the Axxent system provides a therapeutic dose of intracavity radiation directly to the tumour bed, following lumpectomy. The electronic brachytherapy source is tailored to mimic the penetration and dose-rate characteristics of 192Ir (the isotope generally used for high-dose-rate brachytherapy) within the targeted treatment area.
The source itself comprises a disposable, 2.25 mm X-ray tube, integrated into a flexible sheath (with a total assembly diameter of 5.4 mm) attached to a treatment control console (see photo). The assembly is placed into the treatment cavity within a disposable balloon applicator, which serves as a scaffolding or centring device for the radiation source.
In terms of system design, the emphasis is clearly on automation and ease of use, with barcodes and a barcode scanner streamlining the workflow management and an on/off capability to ensure radiation safety.
