Vet, human medicine team up against disease
Vet, Human Medicine Team Up Against Disease
Jim Steinberg, Staff Writer
Posted: 10/27/2010 06:46:03 PM PDT
Maggie, a 10-year-old beagle, was gorging herself with water and urinating uncontrollably. Lucy, an elderly lab/shepherd mix, was staring at walls and arching her back like a cat. Both dogs had advanced cases of the canine form of Cushings disease, the result of a tumor on the pituitary gland.
Every year some 100,000 dogs are diagnosed with this life-changing - and life threatening - disease. Fortunately for Lucy and Maggie, an unusual partnership has formed between a veterinary hospital group in West Los Angeles and Cedars-
Sinai Medical Center.
For about a year, Dr. Adam N. Mamelak, a neurosurgeon who is also co-director of the Cedars-Sinai Medical Center Pituatory Center, and Tina Owen, a veterinary surgeon with VCA West Los Angeles Animal Hospital, have been working to develop minimally invasive surgical techniques to remove those benign tumors in
Pituitary tumors frequently produce Cushing's disease in dogs. The disease results in an excess of a cortisol hormone called ACTH. Without treatment, this canine disease is fatal and the few existing drugs for the condition are usually not curative, have serious side effects and can be very expensive, said David Bruyette, medical director of VCA West Los Angeles Animal Hospital.
While tumors that cause Cushings disease are fairly common in dogs, they are very rare in humans. Cushings disease only occurs in one out of every million people, Mamelak said. Symptoms of the canine version of Cushing's include increased thirst and urination, diabetes, hair loss, thinning skin, increased appetite, and abdominal enlargement. It generally kills its human victims much more rapidly than it does canines, Mamelak said. Mamelak and Owen practiced with canine cadavers before working on the first dog in a clinical trial.
Given the anatomical differences between humans and dogs, the surgery is quite different for each. Mamelak uses his minimally invasive techniques on humans to access the pituitary gland through the nose. But in dogs, the access point least destructive to brain tissue is through the roof of the mouth. To help a veterinary surgeon better see in a small, difficult to access point, Mamelak said a new imaging device he had been studying for human surgery, called VITCOM, was a nearly perfect fit for this type of canine neurosurgery.
The attraction to the partnership for Cedars-Sinai researchers is to gain access to a very large supply of Cushing's disease causing tumors, Mamelak said. Although canine pituitary tumors are not identical to those in humans, they are similar, making canine tumors a good model to study for understanding human illness. Because of the rarity of the disease - and the small size of the tumors that cause it - significant amounts of these tissues are impossible to gather from humans, Mamelak said.
Lucy was the first dog to enter the clinical trial. The nearly 13-year-old canine had an extremely large tumor and the treatment called for removal of both the tumor and the pituitary gland, Bruyette said.
Owner Gina Cangiamila of Los Angeles said that after the surgery, Lucy was blind for about two weeks. After a gradual recovery of several months, Lucy's behavior has returned to normal, she said. "Mamelak is a magician. I am very thankful," she said. Maggie also had a somewhat lengthy recovery from surgery, but now is a happy, active pet, said owner Howard Tarlow of Encino. Bruyette said that the surgery is now out of the clinical trial phase and Owen has surgeries scheduled for pets from Boston and Seattle.
The treatment costs between $8,000 and $10,000. Those costs were waived for pets that were part of the clinical trial. Owen will soon be training veterinary surgeons in the technique from a sister VCA facility in the Boston area. But the ultimate solution will not be surgery, Bruyette said. As a result of the clinical trial surgeries, Cedars- Sinai researchers have identified a substance that shrinks this kind of canine tumor in a laboratory environment.
A clinical trial at VCA West Los Angeles Animal Hospital to see how the substance works on living dogs is in the planning stage, he said.