Canine bladder cancer recurrence is relatively high and its survival rate is low. Ultimately, these two factors contribute to the demise of the dog. Fortunately, it accounts for only about 1 percent of the cancers reported in canines. Dogs usually succumb to the disease within a year, even with radiation treatment, drugs or surgery. About half of the cases see a recurrence, while another 30 percent see an occurrence of cancer elsewhere in the body (metastasis). Factors include the severity of the cancer, the size of the tumor and the stage that the cancer was in at the time of its discovery.
Surgery is the most recommended treatment to stop the spread of the cancer; however, it is not always possible. Sometimes the tumor reappears at an even larger size after surgery. Canine bladder cancer recurrence can be reduced with a newly discovered treatment called Bacillus Calmette Guerin (BCG). BCG treatment is used in conjunction with medication or after surgery to prevent the spread of cancer to nearby organs.
Symptoms
Bladder cancer is highly fatal and usually spreads to other parts of the body, including the lungs and lymph nodes. Typical signs of bladder cancer include:
- Painful urination (dysuria)
- Abdominal pain
- Blood in the urine (hematuria)
- Enlarged kidneys, usually with an obstruction in the urinary tract
- Enlarged kidneys exerting pressure on other organs, causing pain
- Thickening of the bladder
- Papillary projections protruding from the bladder wall
- Bacterial infection
- Tumor
- Urinating often in small volumes
- Enlargement and swelling of the urethra (tube which carries urine out of the body)
- Hardening of the bladder
- Respiratory distress
- Fever
A detailed urinalysis and x-rays can confirm the existence of bladder cancer.
Treatment
Surgery is the only form of treatment for this type of cancer; however, it is not always successful. Surgery only works if the tumor is in an incipient phase and in a location that can be operated on. Often the tumor grows back or the cancer spreads to another organ or appears elsewhere in the body.
The disease can be treated with medications, which usually slow down the progression of the disease but do not cure it. These medications weaken the dog's immune system and necessitate the BCG treatment in order to boost the immune system and increase the dog's chances for survival. Further studies are needed to support the claim that BCG fights cancer cells and is effective in fighting first stage cancer.
Bacterium Shows Promise
BCG treatment shows promise since it causes an immune response, making the dog's body more resistant to any secondary diseases, which sometimes kills the dog before the cancer does. Traditional chemotherapy can only extend the lifespan for 6 months to a year. A new chemotherapy treatment is being developed. Intra-arterial chemotherapy concentrates the treatment by being injected into an artery close to the tumor. It can be cost prohibitive since the entire procedure can run around $8,500. Homeopathic supplements can boost the immune system of the dog but cannot cure the cancer.
The initials BCG stand for the name of the tuberculosis bacterium derived from cows. Initially used as a tuberculosis vaccination, the bacteria are treated so that it cannot cause tuberculosis in canines. Administered through a catheter to the bladder, it activates the immune system, protects the dog from secondary diseases since the immune system is depressed, and creates a response from the body against the cancer cells. Common side effects include lethargy, fever and joint pain. Careful monitoring and antibiotics will be necessary, especially if an infection has occurred.