+ General Considerations

  • Epithelial tumors, in particular TCC, are the most common tumors of the urinary bladder and account for up to 92% of feline bladder tumors
  • Other urinary bladder tumors include SCC, ADC, rhabdomyosarcoma, FSA, CSA, leiomyosarcoma, HSA, chemodectoma, and benign tumors such as leiomyoma and fibroma

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+ Transitional Cell Carcinoma

  • Dogs excrete large quantities of tryptophan metabolites in the urine
  • However, cats metabolize tryptophan differently and do not excrete urinary tryptophan metabolites


  • TCC are either diffuse or located in the fundus or ventral bladder wall in cats
  • TCC are most frequently located in the trigonal area in dogs resulting in urinary tract obstruction


+ Clinical Signs

  • Dysuria, hematuria, pollakiuria, and stranguria
  • Vaginal discharge
  • Urinary obstruction
  • Incontinence
  • Urinalysis and Urine Sediment Cytology

Urinalysis and Urine Sediment Cytology

+ General Considerations

  • Hematuria and proteinuria are consistent findings on urinalysis due to ulceration of the urothelial mucosa
  • Bacteruria, pyuria, and positive urine cultures are common in cats
  • Bladder wash cytology may improve diagnosis capabilities by reducing contaminants

+ Urine Sediment Cytology

  • Neoplastic transitional cells are difficult to differentiate from reactive transitional cells
  • Mesenchymal tumors exfoliate poorly and are rarely diagnosed with analysis of urine sediment

+ Blood Tests

  • Hematology and serum biochemistry findings are usually normal or non-specific
  • Mild to moderate normochromic, normocytic anemia can be caused by either hematuria or bone marrow suppression secondary to chronic disease
  • Uremia may result from neoplastic obstruction of urinary outflow or age-related renal failure

Imaging Studies

+ Survey Radiographs

  • Magining techniques include survey abdominal and thoracic radiographs, contrast radiography, and CT
  • Survey radiographs: sublumbar lymph node enlargement, renomegaly, and metastatic disease in the pulmonary parenchyma or skeleton, particularly lumbar vertebrae and pelvis
  • Positive contrast cystography is useful for identification of mucosal abnormalities and space occupying lesions
  • Excretory urogram is indicated to determine the location and extent of obstructive urinary tract disease when the urethra cannot be catheterized

+ Ultrasonography

  • Recommended to determine the location and extent of bladder involvement, regional lymph node size and appearance, and involvement of adjacent anatomical structures such as the colon
  • Superior to excretory urography and double-contrast cystography in detecting TCC

+ Biopsy

  • Required for definitive diagnosis of urinary tract tumors
  • Techniques include FNA, needle biopsy, catheter biopsy, cystoscopic, and open surgery
  • Percutaneous biopsy procedures are not recommended due to the risk of tumor seeding
  • Inflammation secondary to necrosis and ulceration is common and may result in false-negative findings


+ Surgery

  • Surgical techniques for management of bladder tumors include:
  • Palliative procedures: tube cystostomy ± partial cystectomy
  • Curative-intent procedures: partial cystectomy and total cystectomy with urinary diversion
  • Cystostomy tube can be placed percutaneously or with either laparoscopic or open surgery
  • Complications: stranguria, pollakiuria, hematuria, urine leakage around the stoma, and vesicoureteral reflux which predisposes to ascending UTI and tumor seeding of the upper urinary tract

+ Adjunctive Management

Role of chemotherapy and radiation therapy is unknown