The Food and Drug Administration (FDA) announces the approval of the first canine cancer therapy...

Palladia - A New Anti-Cancer Drug for Dogs
By Janet Tobiassen Crosby, DVM

No one likes to hear the "C" word - cancer. But today the news is good. The Food and Drug Administration (FDA) announced that it has approved the first canine cancer therapy in the US. The drug is called Palladia (toceranib phosphate) and it is used for treatment of (MCT) in dogs.

"In the weeks and months ahead, Pfizer will introduce this new drug to boarded specialists to expand the body of clinical experience with this new therapy. The experience gained during this time will enable us to support veterinarians more effectively when we make the product available for purchase in early 2010," said George Fennell, vice president, Companion Animal Division, Pfizer Animal Health.

Mast cells are produced in the bone marrow and found in connective tissues. They are part of the immune system and release histamine in response to parasites, allergens or trauma. (For example, squeezing this type of tumor can cause it to enlarge in size.) Mast cell tumors are a common skin tumor in dogs and cats, but can be found anywhere in the body. Clinical appearance can vary greatly: raised, hairless, soft, firm, ulcerated, etc., so a fine needle aspirate or biopsy is required for positive diagnosis. A tissue biopsy is needed to stage (grade) the tumor.

Because of the unpredictable nature of this tumor, malignancy is usually assumed until proven otherwise. Wide margins must be obtained when removing these tumors. Lymph nodes and spleen should also be evaluated. MCTs are classified as Grade I, II or III. Grade III is the most severe. Between 7 and 21% of all canine skin tumors are mast cell tumors.

According to the Morris Animal Foundation, 1 in 4 dogs die of cancer. News of this new treatment is encouraging for this common and potentially serious form of cancer. Hopefully this will open the doors for additional anti-cancer therapies in the near future.