Mary Allen
Urothelial carcinomas – tumors of the urinary bladder and urethra often affect middle-aged to old dogs. Scottish Terriers, West Highland White Terriers, Airdale Terriers, and Beagles are more commonly affected.
The urinary bladder collects the urine that is excreted through the urethra. The bladder and urethra are lined with a mucous membrane that seals the body from urine. This mucosa is more exposed to the waste and pollutants found in the urine. The mucosa is constantly renewed to ensure a good seal. If the renewal of the mucous membrane gets out of hand and it grows uncontrollably, benign polyps can form or, in the worst case, uncontrolled malignant growths. These growths bleed easily. The growths narrow the urethra, making it difficult to urinate. With these growths, the natural protection of the mucous membrane against urinary tract infections is lost. If there are problems with urination, a urothelial carcinoma should also be considered, especially in Scottish Terriers, West Highland White, and Airdale Terriers and Beagles.
Symptoms
The first symptoms correspond to those of a urinary tract infection. The urine can also be bloody. There is increased effort when urinating (stranguria), frequent stopping of small amounts (pollakiuria), and an urge to urinate at night (nocturia). The general condition usually remains undisturbed for a long time, so the severity of the disease is often underestimated at the beginning.
Diagnosis
The examination of the urine, the ultrasound examination of the urinary tract, and an X-ray overview of the abdomen often provide the first suspicions. The definitive diagnosis is made by examining (endoscopy) the urethra (urethroscopy) and bladder (cystoscopy). In advanced cases, the endoscopic picture is clear when examined by an experienced urologist. In early stages or in cases of doubt, the histological examination of samples taken through the endoscope using fine tissue forceps confirms the diagnosis. An X-ray examination of the chest and bones, an ultrasound examination of the liver and other abdominal organs, or a computer tomography provide valuable information as to whether the growths have already spread.
Therapy
The first goal of the treatment is to enable the patient to urinate as symptom-free as possible. Lower urinary tract catheterization is a common first line of emergency bladder emptying. Further treatment belongs in the hands of an experienced urologist. This can already restore the patency of the urethra during the first reflection of the urinary tract. For this purpose, the excess growths in the urethra are removed using a laser. This laser treatment can be repeated several times. Alternatively, a tube can be inserted into the urethra (urethral stent) to keep the urethra open for a longer period of time.
Growths that have already spread are treated with drugs that slow down cell growth. A decision is made on a case-by-case basis as to which drug is suitable for which patient.
In most cases, an operation to remove parts of the bladder or the urethra is not advisable, as it results in the mutilation of the urinary tract with a significant reduction in quality of life.
Prognosis
Urothelial carcinoma is growth in middle-aged and elderly patients. In many cases, good quality of life can be restored in the medium term. Regular veterinary checks are required.