A newly established Companion Animal Tumor Registry in two areas of New York state will test a question that has intrigued cancer researchers: Can a geographic database of cancers in dogs and cats warn of possible environmental causes of cancers in humans?

Researchers in the Cornell University Comparative Cancer Program and Center for the Environment will begin asking veterinarians in Tompkins and Nassau counties voluntarily to report cancers diagnosed in clients' pets, identifying them by residential ZIP code. Once logistics are worked out, the pilot project might be expanded to other areas of New York state or even nationwide, allowing researchers to merge animal-cancer data with parallel databases for human-cancer incidence. Researchers also will seek to collect and analyze tissue, blood and urine samples from pets diagnosed with cancer.

Start-up funding for the project was arranged by New York State Sen. Michael Balboni and Nassau County Legislator Lisanne Altmann. Funds will provide for a pilot project to determine the feasibility of a full study.

"We're beginning to realize that cancer in companion animals may provide a vastly underutilized resource for cancer risk assessment in humans," says Rodney L. Page, director of the Comparative Cancer Program and professor of clinical sciences in Cornell's College of Veterinary Medicine. "Pets share the human environment, and that includes our mutual exposure to potentially carcinogenic compounds. In some cases, companion animals' exposure may be more intimate because they are in closer contact, for example, with chemicals applied to lawns or carpets or they are drinking contaminated water."

Links between pesticides, diet and other factors and cancer are examined at the Breast Cancer and Environmental Risk Factors (BCERF) program in Cornell's Center for the Environment http://www.cfe.cornell.edu/bcerf/ . Says Suzanne Snedeker, BCERF's associate director of translational research, "Naturally occurring cancers in pets have similar pathological features and biological behaviors as tumors in humans but with two important differences that can work to our advantage in this project. Cancers in pets often progress more rapidly, thus reducing the time required to make conclusions about causal associations, and in contrast to human cancers, cancer development in companion animals is not subject to confounding risks such as smoking and alcohol consumption."

Adds the Cornell Veterinary College's Page: "It is always unfortunate when a family pet develops cancer, as 50 percent over age 10 will during their later years. But there are two sources of consolation for the human companions: Advanced treatments are becoming available, and many of these pets can be cured. Secondly, knowledge of where these animals lived when they developed cancer can improve our understanding of the causes of cancer in all kinds of animals, including humans, and help to prevent their occurrence."

The Companion Animal Tumor Registry will capitalize on a new geographic mapping system for carcinogenic exposure on Long Island, available at http://www.healthgis-li.com/ . The animal cancer data will be merged with human cancer incidence data in New York state, available at http://www.health.state.ny.us/nysdoh/cancer/csii/nyscsii.htm .