Cornell University researchers are setting up a companion animal registry to measure cancer incidence and test whether a geographic database of pet cancers can help warn of environmental problems that may cause human cancers. If successful, the registry may help improve health care for people as well as pets. Developing a cancer registry for animals is certainly not a new idea. The first companion animal tumor registry, sponsored by the National Cancer Institute, was created in the late 1960s and examined the incidence of tumors in dogs and cats in two California counties. Since then, various registries have been developed for pets, but only some of these determined incidence, and they are not as comprehensive as the 1960s registry, covering various types of cancers with a high degree of accuracy. The new registry will hopefully provide much-needed, up-to-date information. "We aren't working with accurate information when it comes to trying to plan prevention and early diagnosis strategies," said Dr. Rodney Page, director of the comparative cancer program at Cornell. "The fact that we don't know what the changes have been over 30 years is a significant deficit in the field of oncology." Dr. Robert Rosenthal, head of medicine at Veterinary Specialists of Rochester, N.Y., agrees. "There is no sort of ongoing, centralized source of good information (about cancer incidence)," said Dr. Rosenthal, who is also president of the Specialty of Oncology within the American College of Veterinary Internal Medicine. Looking at incidence information over a period of time, he says, would allow veterinarians to know whether incidence was changing. Then, trends could perhaps be correlated with factors such as nutrition, which might need modifications. But improving pet health is not the only goal of this ambitious project, which has received funding from the state of New York and the Animal Cancer Foundation for the first year. The Cornell-based study will work in concert with a National Institutes of Health-funded project that studies the unusually high breast cancer rates on Long Island, N.Y. Through this project, which began in 1993, researchers have created maps showing the distribution of human cancer cases and possible carcinogen sources, such as factories and toxic waste dumps. The Cornell scientists will examine whether a correlation exists between animal and human cancer. If one does, they hope to use pets as sentinels for detecting high-risk cancer areas and identifying possible environmental sources for tumors before they start showing up in humans. Pets might serve as an early warning sign because their cancers have similar pathologic features to human cancers as well as similar behaviors, such as being potentially invasive, metastatic, and capable of responding to similar therapies.
 Causal associations may be easier to make with animal cancers because they progress more rapidly than human cancers. In addition, in contrast to human cancers, cancer development in companion animals is not subject to confounding risks, such as smoking and alcohol consumption, to the same extent as in humans. The project will focus first on Long Island's Nassau County, an area with high cancer rates, and Tompkins County, an area in upstate New York that will serve as a control. According to Dr. Page, the first year of funding is being used to put the nuts and bolts in place, such as networking with veterinarians, identifying methods to register the results of cancer biopsies, and identifying ways to estimate pet populations. Currently, cancer in animals is not a reportable disease. "There are some really significant obstacles to trying to accomplish this," said Dr. Page. "Making cancer a reportable disease would essentially make it equivalent to rabies and food-and-mouth disease. The bureaucracy that would be involved in that is pretty hard to justify at this time, so it would have to be accomplished voluntarily at this time, which requires a lot of support and communication." According to Debbie Winn, PhD, acting associate director for the epidemiology and genetics research program at the National Cancer Institute, the new registry could help estimate the magnitude of cancer and follow trends in its incidence and distribution. It could also help formulate and evaluate control and prevention measures as well as detect outbreaks and generate appropriate interventions. "If you are looking over time and see a change that perhaps lasts for two years, or looks particularly high, or is in a cancer that's rare, for example, that would be cause for concern," Dr. Winn said. Dr. Page says that if they can overcome the obstacles, they will begin collecting data early next year. The project, so far, has received enthusiastic support from veterinarians, legislators, advocates, and scientists. "The response I have gotten so far is extremely encouraging, overwhelming, really," Dr. Page said. "The comment I get most is 'this should have been done many years before.'" If successful, the project will be expanded to other areas of New York and other states.
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