Page 669 - Withrow and MacEwen's Small Animal Clinical Oncology, 6th Edition

CHAPTER 30 Tumors of the Urinary System 647

In dogs with confirmed or suspected iUC, evaluation should tract imaging). To avoid the risk of seeding iUC through cysto-
include an assessment of overall health (complete blood count, centesis, urine may be collected by free catch or catheterization.
Catheterization must be performed carefully to avoid penetrating
serum biochemistry profile, urinalysis, ± urine culture) and stag-
VetBooks.ir ing of the cancer (three-view thoracic radiograps, abdominal the diseased bladder or urethral wall. Urinary tract imaging is used
to assess the tumor location for potential surgical intervention
ultrasonography or computed tomography [CT], and urinary

A B C

D E F

G H I

• Fig. 30.2 Images from cystoscopy of dogs with invasive urothelial carcinoma (iUC, A–E) and biopsy material
obtained (F), and images of dogs with polypoid cystitis (G–I). TCC can appear as a ruffled frond-like mass,
a solid smooth mass, or as polyp-like lesions. High-quality images can be obtained with rigid cystoscopes
typically used in female dogs (A, C–E) and in digital flexible scopes used in male dogs (B, image from a
male Scottish terrier). The use of a cystoscopic wire stone basket (D, E) allows collection of larger biopsies.
Regardless of the biopsy instrument used, however, cystoscopic biopsies are relatively small, and placing the
samples in a tissue cassette (F) may facilitate processing. Polypoid cystitis (G–I) appears very similar to TCC,
but it is treated differently and has a better prognosis than TCC. Images (H) and (I) are from a dog with polyp-
oid cystitis before (H) and after (I) a month of clavamox treatment alone with no other therapy. The polpys had
regressed by more than 80% (I) at the time of rescoping. Cases such as this one emphasize the importance
of histopathology in the diagnosis of urinary tract masses, especially when selecting therapy, and even more
so when dogs are participating in clinical trials. (Courtesy L. G. Adams and D. W. Knapp, Purdue University.)