Transitional cell carcinoma (TCC) in a dog

The following are cytology smears prepared from a urethral catheter suction biopsy of a urinary bladder mass in a 12-year-old female Labrador Retriever with a clinical history of dysuria and haematuria.

Fig 1. There is a cluster of pleomorphic neoplastic epithelial cells. The nuclei range from 2.0-3.5 RBCs in diameter and contain multiple prominent nucleoli (x1000).
Fig 2a & 2b .Some of neoplastic cells contain pink intracytoplasmic inclusion material known as Melamed Wolinska bodies (black arrows); this is something that is commonly seen in neoplastic epithelial cells of urothelial origin (x1000).
Fig 2b.
Fig 3. There is also evidence of secondary bacterial infection in this case – note the neutrophil and the extra- and intracellular bacteria (red arrows, x1000).

Final Diagnosis

Carcinoma, consistent with a transitional cell carcinoma (TCC)


Transitional cell carcinomas are malignant and locally invasive neoplasms. They most commonly involve the urinary bladder, urethra, prostate (secondary to prostatic invasion by a prostatic urethral TCC) and kidney. Unfortunately, these tumours carry a high risk of metastasis, particularly to the regional sublumbar lymph nodes, lungs and bone (e.g. pelvic and lumbar).