Feldene to Treat Transitional Cell Carcinoma

Lili Duda, VMD
Last Modified: November 1, 2001

Dear OncoLink "Ask the Experts,"
I would like to know what your thoughts are on using feldene/piroxicam as opposed to prednisone in the treatment of Transitional cell carcinoma (TCC) in my dog. I am frightened about the side effects of prednisone and I do not know anyone who has used feldene with their pet. My own veterinarian is not familiar with it. Any help at all would be greatly appreciated.

Lili Duda, VMD, Editor of the OncoLink Veterinary Oncology Section, responds:

Transitional cell carcinoma of the bladder causes symptoms primarily due to partial obstruction of the urinary tract, secondary infection and inflammation of the tumor. Therefore, treatment is aimed at

alleviating the infection/inflammation which can often cause significant improvement in clinical signs, and
decreasing the size of the tumor. Antibiotics are used to treat infection. They can be given preventatively as a continual low dose, or used intermittently when clinical signs of infection occur. Urinalysis and culture & sensitivity can be used to help identify infections, or they can be treated based on symptoms.
Prednisone is an excellent steroidal anti-inflammatory. At the lower anti-inflammatory dosages the side effects should be minimal, and consist mainly of increased drinking and urination, and increased appetite. Long-term or chronic side effects take months to years to develop and are most likely not a concern in your dog's case.
Feldene (piroxicam) is an excellent non-steroidal anti-inflammatory, similar to ibuprofen (Motrin). It works very well for inflammation associated with cancer. Effects can be seen in 24 to 48 hours. In addition, it has anti-tumor effects in certain tumors, including transitional cell carcinomas, independent of its anti-inflammatory effects. These effects are thought to work through the immune system. It can take weeks to months to show significant decrease in tumor size for the subset of tumors in which it will work. The primary side effects are similar to those in people; namely gastrointestinal irritation or ulceration. Therefore, the medication is always given with food and often given with the anti-ulcer medication Cytotec (misoprostol). This drug should also not be given to dehydrated patients or patients with poor kidney function. Feldene is being used with increasing frequency in many veterinary cancer patients (it is also used for arthritis at lower dosages) and is our first choice for many patients with transitional cell carcinoma.
If you or your veterinarian have not already done so, please consult a qualified veterinary oncologist to further explore the treatment options for your pet.
Best of luck with your dog. I hope that Feldene is an option for her and that it improves her quality of life.