Tumors of the Urinary Tract Flashcards
Incidence of canine urinary bladder tumors?
2%
List 7 risk factors associated with canine bladder tumors?
exposure to flea control (old versions), lawn chemicals and cytoxan, obesity, female gender, neuter status, and a very strong breed predisposition on (OR vs mixed breed: Scotties 21x, Eskimo 6.6x, Shelties 6x, Westies 5.8x).
What can lower the risk for bladder tumors?
Eating vegetables (>3x/week).
Most common bladder tumor?
Other less common bladder tumors?
invasive urothelial carcinoma (iUC) or iTCC is the most common canine UB cancer
less frequent tumors - SCC, adenocarcinoma, undifferentiated carcinoma, rhabdomyosarcoma, LSA, HSA, fibroma and sarcomas.
What is the proposed tumor grade for TCC?
High or 3=70%, intermediate or 2=29%, and low or 1=1% (n=232 iUCs, Knapp, ILAR J, 2014)
What % of tumors extend to urethra and prostate?
56%, 29%
What % have regional LN and distant mets at time of diagnosis?
16%, 14%
What % have mets to lungs?
50%
Other locations of metastasis for TCC?
liver, adrenals, spleen, heart, GI tract, brain and bone (9-14%), +/- skin (seeding or extension).
Why do TCC patients have elevated BUN?
Abnormal urea transporters in the tumor
BRAFv5952 mutation is present in the urine of ___% of canine iUC ?
>80% (19/23 iUC vs 0/37 normal UB or cystitis)
List 5 other DDx to consider for common presenting clinical signs for iUC?
chronic bacterial, granulomatous or polypoid cystitis, urethritis, calculi or other neoplasia
What are 2 IHC markers for iUC?
Uroplakin II +/-GATA-3 can be used to define urothelial origin.
What % of bladder can be safely resected?
50%
Important studies:
n Marvel, et al VCO 2017: n=37 dogs - partial cystectomy + NSAID +/- chemo, DFI=235 (8 mo) and MST=348 days (12 mo). Subset of n=22 dogs - surgery + piroxicam SID +/- chemo, MST=722 days (24 mo)
Knapp, et al ILAR J2014: n=9 dogs 4 surgery (3=complete margins) + deracoxib SID, MST=749 days.
Upton, et at JAVMA 2006: Transurethral CO2 laser ablation + NSAID + chemo, outcome not better than medical therapy alone and risks include urethral perforation and stenosis.
What is the MST with stent placement?
Variable. MST=20-78 days (2-536) from urethral stent placement in one study of iUC and prostatic carcinoma, and MST=57 days in one study with ureteral stents.
Follow up with adjuvant therapy (NSAID, chemo, RT) is strongly recommended and has been noted to improve MST=251 (8-536) (Blackburn, JAVMA 2013).
What is the main complication associated with stent placement and is seen in what % of dogs ?
What are the other complications?
Mainly incontinence in 25-39% of dogs,
Stent migration, collapse or blockage from tumor growth; also lower urinary signs (hematuria) may not resolve
RT and iUC
lower rates of adverse events, with acute side effects being mild and transient (colitis, stranguria, erythema) and late side effects being less common. (urinary or rectal stricture, <10%). A PFI— 317 and MST=654 days was reported in one study with IMRT, and an ORR=61% and SD=38% in another study with 2.7Gy x 10 daily treatments
What is the RR for VBL + piroxicam and MST?
VBL alone?
VBL + Piroxicam (58%, 199 days) > VBL alone (22%, 143 days), but MST was higher for VBL alone Piroxicam alone (531 days) > VBL + Piroxicam (299 days). (Knapp et al, Bladder Cancer, 2016).
ORR for mitoxantrone + piroxicam? MST?
Mitoxantrone + Piroxicam: ORR=35%, PFI=194 and MST=291 days (Fulkerson et al, Vet J, 2015).
ORR for carboplatin + piroxicam? MST?
Carboplatin + Piroxicam: ORR=38%, MST=161 days. Tends to be thought as more effective but less tolerated than mitoxantrone combination (Fulkerson et al, Vet .I, 2015).
Low dose metronomic chemotherapy for iUC and MST?
Leukeran, n=31 heavy treated dogs, resulted in 3% PR and 67% SD, PFI-119 and MST=221 days (Schremp et al, JAVMA, 2013). Good quality of life, but risk of chronic myelosuppression.
ORR for single agent COX inhibitor?
ORR=15- 20% (1%PRs) and SD=55% of dogs with iUC. Knapp (ILAR J 2014): n=94 iUC dogs on piroxicam, CR=3%, PR=18%, SD=59%, PFI=120 and MST=244 days, toxicity (grade 1 or 2 GI)=31% PPIs can increase GI toxicity.
List 4 reasons female dogs (especially with urethral disease) are more predisposed to UTIs with iUC?
1) urine retention, 2) acquired anatomical defects due to tumor, 3) damaged urothelium, and 4) +/- compromised immunity.