Transitional cell carcinoma of the urinary bladder in a spectacled bear ( Tremarctos ornatus )

lymph node taken at the time of surgery did not reveal neoplastic cells. Thoracic radiographs taken at the same time showed no abnormalities and no evidence of metastasis. Treatment with 20 mg (0·1 mg/kg) piroxicam (Piroxicam; Mylan Pharmaceuticals) orally once a day was initiated. Since a literature search did not yield a reference for piroxicam in bears, the initial treatment dose was intentionally kept low. When it was clear that the bear tolerated the dose well, the frequency of medication was increased to 20 mg orally twice a day. Although the piroxicam was administered as a treatment for the TCC, it had the side benefit of providing pain relief for the lumbar spondylosis, and within weeks the keepers noted that the bear was moving around much more easily. The bear was re-anaesthetised five months after the initial diagnosis, using the anaesthetic protocol described earlier. Repeat thoracic radiographs, abdominal radiographs, a double-contrast cystogram and abdominal ultrasonography revealed no evidence of the primary tumour or metastasis, and no change in the vertebral spondylosis. Approximately one year after the initial diagnosis, the bear was euthanased due to severe pain, presumably secondary to the lumbar spondylosis. There was no gross evidence of TCC in the urinary bladder or anywhere else in the body at postmortem examination, but there was histological evidence of metastasis to one lumbar lymph node. The most common clinical presentation for TCC is persistent haematuria that is unresponsive to antibiotics (Norris and others 1992, Mutsaers and others 2003). Diagnosis is based upon physical examination, cytology of urine sediment, radiography, abdominal ultrasonography, contrast cystography and, in some cases, cystoscopy (Norris and others 1992). Ultrasound-guided fine-needle aspiration of a TCC has been reported to be a successful diagnostic method, but this procedure has been associated with the implantation of neoplastic cells in the ventral abdominal wall in rare cases, and may therefore not be the safest diagnostic technique (Nyland and others 2002). More recently, a less invasive urine dipstick diagnostic test, the bladder tumour-associated antigen test, which was developed for use in human beings, has shown promise as a screening test in domestic dogs (Henry and others 2003). The bear was treated with piroxicam, a non-steroidal antiinflammatory drug, which has been shown to have in vitro efficacy against canine transitional cell tumours (Knapp and others 1994, Knapp 1995, Mohammed and others 2002). The mechanism of action of this drug is not clear, but it does not appear to have direct effects on the tumour (Borjesson and others 1999). Instead, piroxicam is thought to exert immunomodulatory effects through the inhibition of prostaglandins Transitional cell carcinoma of the urinary bladder in a spectacled bear (Tremarctos ornatus)