Tumors of the Urinary System Flashcards
What are the three main goals of surgery as a localized therapy for iUC?
AH
- Obtain tissue for a definitive diagnosis.
- Eradicate lesions amenable to wide excision, such as tumors distant from the trigone.
- Relieve urinary tract obstruction.
Why is local recurrence common after partial cystectomy for iUC?
AH
field effect
The presence of multifocal lesions suggests a field effect or malignant transformation of the entire urothelium due to carcinogen exposure
What is the rate of incontinence after urethral stent placement in dogs?
AH
25-40%
What kind of radiation scheduling is preferred in treatment of iUC based on in vitro studies? (large dose less fractionation or low dose more fractionation?)
AH
Higher doses and less fractionation.
Although iUC cells were generally thought to be sensitive, but an in-vitro study suggested moderate radioresistance (low a/b ratio) , supporting higher doses and less fractionation
What were the complications associated with the early use of large doses and less fractionation in radiation therapy?
AH
Chronic colitis, cystitis, and urethral strictures, with little improvement in MST compared to medical therapy alone
What are the acute side effects of intensity-modulated and image-guided radiation therapy?
AH
Mild and self-limiting, including colitis (38%), erythema or hyperpigmentation (19%), and stranguria (5%)
What are the late complications of intensity-modulated and image-guided radiation therapy?
AH
Urethral stricture (9%), ureteral stricture (5%), or rectal stricture (5%)
What were the median event-free survival and overall MST in a series of dogs treated with intensity-modulated and image-guided radiation therapy?
AH
Median event-free survival was 317 days, and the overall MST was 654 days
What outcomes were reported in a report of dogs with urogenital carcinomas treated with low-dose palliative RT plus antineoplastic drugs?
AH
CR or PR in ~60% and SD in ~40% of dogs.
Why is simultaneously combining multiple chemotherapy agents not currently recommended for the treatment of canine iUC?
AH
he benefit has not been determined, toxicity is likely to increase, and the potential development of resistance to multiple drugs at the same time could limit the options for subsequent therapy
Compare MST in dogs receiving vinblastine alone followed by piroxicam alone compared to those receiving both drugs concurrently?
AH
The MST was significantly longer in dogs receiving vinblastine alone followed by piroxicam alone (531 days) than in dogs receiving the two drugs given concurrently (299 days)
What is a concern with increased use of chlorambucil for treatment of canine iUC?
AH
Chronic myelosuppression persisting for weeks to months has emerged as a concern
What injectable demethylating agent has shown promise in iUC?
AH
5-azacitidine, which resulted in PR in 22% and SD in 50% of treated dogs
What localized drug delivery methods have been used in dogs with iUC?
AH
Intravesical mitomycin C and photodynamic therapy (PDT)
Most common form of canine urinary bladder cancer
invasive urothelial carcinoma
Most common location of urothelial carcinoma
trigone region of the bladder
Distant metastatic sites for urothelial carcinoma
Lungs (most common), liver, kidney, adrenal gland, spleen, bone, skin, heart, brain, and GI tract
Activity of urothelial carcinoma in the abdominal wall
Typically aggressive and poorly responsive to medical therapy
Risk factors for canine bladder cancer
Exposure to older generation flea control products and lawn chemicals, obesity, possibly cyclophosphamide exposure, female gender, and breed-associated risk (Scottish terriers)
What factor has been shown to lower the risk for urothelial carcinoma?
Dogs that ate vegetables at least three times per week in addition to their dog food
TNM Clinical Staging System for Canine Bladder Cancer
T - Primary Tumor
- Tis: carcinoma in situ
- T0: No evidence of a primary tumor
- T1: Superficial papillary tumor
- T2: Tumor invading the bladder wall, with induration
- T3: Tumor invading neighboring organs
N - Regional Lymph Node (Internal and External Iliac Lymph Node)
- N0: No regional lymph node involvement
- N1: Regional lymph node involved
- N2: Regional lymph node and juxtaregional lymph node involved
M - Distant Metastases
- M0: No evidence of metastasis
- M1: Distant metastasis present
What paraneoplastic syndrome is associated with renal cystadenocarcinoma and uterine tumors in GSDs?
nodular dermatofibrosis
A mutation in which gene results in nodular dermatofibrosis? Which human syndrome is this similar to?
FLCN
Birt-Hogg-Dube syndrome
What CBC abnormality may be seen as a paraneoplastic syndrome of renal neoplasia in dogs?
Polycythemia
