New cancer therapy tested on dogs first

Madison, Wis.-University of Wisconsin-Madison veterinary clinicians are evaluating cancer radiation that can selectively irradiate animal tumors without interfering with other tissue.

Part of a $10 million, five-year National Institutes of Health grant,clinicians, Dr. Lisa Forrest (radiology) and Dr. David Vail (oncology) areteaming with physicians, medical physicists and computer experts to testa clinical helical tomotherapy unit installed at the university's ComprehensiveCancer Center. The unit will be tested on canines first.

Helical tomotherapy combines a linear accelerator (a radiation therapymachine) with helical computed tomography (a CT imaging machine). The unit,developed by Dr. Thomas R. Mackie, professor at the university, uses onlineimaging of the tumor and surrounding sensitive normal tissues to guaranteeprecise treatment.

Dogs with spontaneous nasal tumors will be the first "guinea pigs"for the testing. The new method will enable doctors to preserve an animal'seyesight by targeting treatment to the tumor, while avoiding nearby tissues.

As of now, the unit is considered expensive for most veterinary purposes.

However, Forrest says at the very least, there's a chance the universitywill be able to continue to use the equipment for select cases.

"Animals don't have health insurance, so it's not likely to becomecommon," she says.

The treatment is highly computerized, involving a medical physicist andcomputer personnel to operate it. M