Exam 4 - Tumors of the Urinary System Flashcards
what is the most common type of human bladder cancer? what are the 2 distinctions of this type?
TCC
invasive - involves deep layers of the bladder
non-invasive - involves only the transitional epithelium
most humans will have lower levels - will go to a doctor quicker
what is the occurrence of metastasis of dogs with urinary bladder tumors at the time of diagnosis? what is important to consider about this causing mortality?
relatively low at the time
16% nodal metastasis
14% distant metastasis
at time of death, 50% had distant mets
most patients met their end due to local disease - not metastatic disease
where are canine bladder tumors most commonly located?
trigone region
56% have urethral involvement
29% have prostate involvement
what is the most common bladder tumor that occurs in canines? what are some others that have been reported?
urothelial cell carcinoma - intermediate to high grade papillary infiltrative tumors (most all higher grades)
others - SCC, adenocarcinoma, rhabdomyosarcoma, lymphoma, & hemangiosarcoma
what is the TNM for staging bladder cancer?
T - primary tumor
N - regional LN
M - distant metastasis
what does TisNoMo mean for staging bladder cancer?
Tis - carcinoma in situ
No - no regional lymph node involvement
Mo - no evidence of metastasis
what does ToN1M1 mean for staging bladder cancer?
To - no evidence of primary tumor
N1 - regional lymph node involvement
M1 - evidence of distant metastasis
what does N2 mean for staging bladder cancer?
regional lymph node & juxtaregional lymph node involvement
what does T2 mean for staging bladder cancer?
tumor is invading the bladder wall
what does T3 mean for staging bladder cancer?
tumor is invading neighboring organs
T/F: 78% of dogs have T2 tumors at diagnosis & 20% have T3 tumors at diagnosis of bladder cancer
true
what breeds are at risk for bladder cancer?
scottish terrier - 18x the risk compared to all other breeds
shelties & beagles - 4.5x the risk
what are some known risk factors for bladder cancer in dogs?
exposure to older generation flea control products
lawn chemicals
obesity
cyclophosphamide exposure - chemo/metronomic long term
sex (female > male, neutered > entire rest of population) - male dogs pee on more things so less time for carcinogens to hang out in the bladder
what did the study on herbicide exposure & risk of transitional cell carcinomas in scottish terriers find?
significantly higher risk in dogs that were exposed to lawn herbicides alone or herbicides & insecticides
dogs that ate veggies at least 3x a week had a reduced risk
very weak data lol
what are the common clinical signs seen with bladder cancer?
hematuria, dysuria, pollakiuria, & stranguria
what should be done when working up a patient for bladder cancer?
physical exam
cbc, chem, ua - free catch or catheter
staging - thoracic rads/abdominal ultrasound
T/F: it is okay to do cystocentesis for collecting urine in a dog with suspected bladder cancer
nope - avoid this
what are some differentials you should have for bladder cancer?
other neoplasia
chronic cystitis/polypoid cystitis
fibroepithelial polyps
granulomatous cystitis
calculi
how may you get histopathology for diagnosing bladder cancer in dogs?
cystotomy, cystoscopy, or traumatic catheterization (rare)
avoid surgical biopsy (high risk of seeding!!!)
why do you need to do further diagnostics if you see neoplastic cells in a urine sample from a dog you believe has UCC?
these are indistinguishable from reactive epithelial cells associated with inflammation!!!
what is the CADET BRAF urine test? why is it helpful?
DNA based diagnostic test that is able to detect the presence of the BRAF gene in malignant cells shed into the urine of tumor bearing dogs!
90-95% of dogs that have UCC have the BRAF mutation gene - the mutation is not found in the urine of healthy dogs or dogs with other non-UCC forms of bladder disease!!
what would you run a CADET BRAF test on?
voided urine sample!!!
what are the advantages of using a CADET BRAF urine test?
convenient, non-invasive option that is very sensitive - diagnosis in > 95% of cases with bladder & prostate cancer
afforable, $220
robust test that is highly specific
how is cystoscopy used to diagnose bladder cancer?
biopsy is done via transurethral cystoscopy & cystotomy for diagnosing TCC in the bladder & urethra - may not get diagnostic samples
diagnostic sample obtained in 96% of female dogs & 65% of male dogs - females have a larger urethra, so easier for them
in poorly differentiated carcinomas, uroplakin III may be helpful in distinguishing TCC from other carcinomas (expressed in > 90% of cases)
what are the disadvantages of using ultrasound for diagnosing bladder cancer in dogs?
measurements of bladder tumors are affected by the changes in operator of the ultrasound & bladder volume
this is significant enough to change response criteria!!!
use CT instead preferably
what are some indications for surgical treatment of bladder cancer?
need to obtain a tissue diagnosis - your last resort!!
removal of the mass from the bladder if not affecting the trigone!!
maintaining or restoring urine flow!!!
T/F: field carcinogenesis limits the beneficial effect of surgery in dogs with bladder cancer
true
what are the major risks of surgery for a patient with bladder cancer?
without strict surgical oncology principles, the risk for seeding the disease in the abdominal cavity & abdominal wall is very high
what is the median survival time for patients receiving surgery as treatment for bladder cancer?
57 days
T/F: patients undergoing cystotomy with bladder cancer are significantly more likely to have abdominal wall metastasis
true
what are the complications associated with urethral stenting as a treatment for bladder cancer?
incontinence (30% of cases)
re-obstruction
stent migration
what is the median survival time for patients receiving non-surgical urethral stenting as treatment for bladder cancer?
78 days
addition of chemo following stent placement increased MST to 250 days
when may you use urethral stenting in a dog with bladder cancer? what is the advantage of using this approach?
indicated in dogs with urethral obstruction
resolution of the obstruction can be achieved in approximately 98% of cases
what is the median survival time for patients receiving non-surgical palliative ultrasound guided endoscopic diode laser ablation as treatment for bladder cancer?
MST 360 days - a lot of animals in this study developed resistant UTIs
what complications are seen with palliative ultrasound guided endoscopic diode laser ablation as treatment for bladder cancer?
stranguria, hematuria, stenosis, spread of tumor into urethra, urethral perforation, bacterial cystitis (50%, 36% resistant UTI)
what medical therapy may be used for treating bladder cancer in dogs?
single agent COX inhibitor - piroxicam & deracoxib, want a COX2 inhibitor (piroxicam may be too hard on the gi tract with chemo)
chemotherapy - using it to try & slow down & stop tumor growth, not to shrink it
mitoxantrone & piroxicam
cisplatin
carboplatin
what clinical signs are seen in cats with bladder tumors?
hematuria, stranguria, pollakiuria, & concurrent UTI
what is the median age of diagnosis of cats with bladder tumors? what was the median survival time at diagnosis?
15.4 years
MST 261 days
rarely treat them other than symptomatically because of so many comorbidities - likely slowly progressive in cats
what is the most common primary renal tumor in dogs?
renal cell carcinoma - 50-60% of all primary tumors
others - hemangiosarcoma, nephroblastoma, TCC, sarcoma, & lymphoma (often bilateral)
T/F: primary tumors are more common in the kidneys than tumors that metastasize from other locations
false - mets are more common
what are the characteristics of canine renal tumors in german shepherds?
inherited disorders - legs covered in fibrotic dermal lesions, if you see this, check their kidneys!!!
dermal fibrosis & fibromas
renal cyst adenocarcinoma
why do we see renal tumors more commonly in german shepherds?
dominantly inherited missense mutation in a tumor suppressor gene - FLCN (folliculin) similar to birt-hogg-dube syndrome in humans
what clinical signs are seen with canine renal tumors?
usually non-specific - anorexia, weight loss, polyuria, lethargy, hematuria, & back pain
what clinical staging is indicated for renal tumors in dogs?
cbc, chem, ua - look for anemia or polycythemia
thoracic rads - look for mets
abdominal ultrasound/ct - ct preferred over ultrasound
gfr via scintigraphy
what treatment is typically indicated for canine renal tumors? what was the median survival time with this treatment?
nephrectomy
16 months
what is the most common prostate tumor? what is their origin? what breeds are predisposed?
carcinomas most common - adenocarcinoma & TCC
urothelial or ductal in origin - androgen independent (humans acinar origin & androgen dependent!)
scottish terriers
shetland sheepdogs
T/F: castrated dogs may be at an increased risk of prostatic tumors & metastasis
true
what are some common clinical signs associated with prostatic tumors in dogs?
prostatomegaly, hematuria, dysuria, stranguria, dyschezia, tenesmus, & bacteriuria
severe bone pain & pathological factors
prostate will feel very irregular
what are some differentials you should consider for prostatic tumors?
BPH
prostatic & paraprostatic cysts
prostatitis
other prostatic neoplasia
how are prostate tumors characterized in dogs?
time of diagnosis characterized by local invasion with high propensity for regional & distant metastasis
what staging is indicated for prostate tumors in dogs?
physical exam - enlarged on rectal exam, large, firm, irregular, asymmetrical, +/- painful prostate
cbc, chem, ua
thoracic rads
abdominal ultrasound
advanced imaging - ct scans
what are your diagnostic options for prostatic masses in dogs?
ejaculation, traumatic catheterization, prostatic massage, prostatic wash, ultrasound guided FNA/cytology, surgical biopsy, & CADET BRAF urine test
what are your options for local treatment of prostate tumors? why do we not recommend removal of the prostate?
electrosurgical transurethral resection - rapid palliation but side effects limit clinical application (short survival times)
incorporation of radiation therapy!!!! piggy back them with tyrosine kinase inhibitors
too many risks to the point that dogs that did survive had a much lower quality of life
T/F: bladder cancer in humans is associated with smoking
true
T/F: in intact dogs, or dogs that were castrated later in life, it can be normal to have mineralization of the prostate
true - not necessarily indicative of cancer in these cases
