Canine-transmissible venereal tumor (CTVT), also called Sticker's sarcoma, can spread from dog to dog through transmission of tumor cells, according to a study published in Cell (2006;126:477–487).
Although most specialists in the field had already accepted this conclusion, there were no definitive data backing up the assertion, wrote the researchers, led by Dr. Claudio Murgia, a veterinarian from the MRC/UCL Centre for Medical Molecular Virology in the Division of Infection and Immunity at University College London.
He and his colleagues conducted DNA tests on tumor and blood samples from 16 unrelated dogs affected by canine transmissible venereal tumor in Italy, India, and Kenya. Tumor samples taken from 24 animals in Brazil, the United States, Turkey, Spain, and Italy were also examined.
The results showed that DNA isolated from the tumor did not match that of the blood sample from the host. However, the tumors were closely related to one another, stemming from a single cancer clone that diverged into two subclades.
The idea that cancer may be spread by cell transfer has attracted renewed interest due to the recent emergence of a facial tumor that may be transmitted by the bite of the endangered Tasmanian devil, according to the authors.
They said that while they were not aware of any reports of sexual transmission of tumor cells in humans, the possibility warrants investigation in transplant patients and immunodeficient individuals.
In an accompanying review of the article, Bridgett M. vonHoldt, MS, of the Department of Ecology and Evolutionary Biology at UCLA, and Elaine A. Ostrander, PhD, Senior Investigator and Chief of the Cancer Genetics Branch in the National Human Genome Research Institute, wrote that the study raises important issues for conservation biology and evolution.
“At present, CTVT can enter the wild canid populations through physical contact between individuals or mating between closely related species,” she said. “For highly endangered canids, exposure to CTVT could theoretically create an immediate threat to the population's survival.”
Oral PCA Device Granted US Patent
The US Patent and Trademark Office issued a utility patent for the MOD (Medication On Demand) Patient Controlled Timed Oral Medication Dispenser, manufactured by Avancen.
A news release from the company notes that the product, which makes it possible for patients to access their own oral pain medication by using a bracelet programmed with a radio frequency identification (RFID) code, is the first and only patient-controlled analgesia device for oral medications to enter the marketplace.
The device also includes a pain scale so patients can record their pain levels. In order for the requested medication to be dispensed, the patient touches a number on the pain scale to activate the RFID reader and then swipes the RFID wristband over the reader.