JVD 2015 Flashcards
What tissue does SCC in cats commonly arise from?
Gingiva and mucosa of the maxilla, mandible, tongue, sublingual or tonsil region.
Oral tumours account for ___% of all feline tumours and approximately ____% of these tumours are malignant.
Oral tumours account for 10% of all feline tumors, and approximately 90% of these oral tumors are malignant
SCC accounts for ______% of feline malignant oral tumours
60-70%
According to a study by Gendler A, Lewis JR, et al. Computed tomographic features of oral squamous cell carcinoma in cats: 18 cases (2002-2008). J Am Vet Med Assoc 2010; 236: 319-325
Metastatic rate of SCC to the mandibular LNs is _____%
35.7%
According to Gendler A, Lewis JR, et al. Computed tomographic features of oral squamous cell carcinoma in cats: 18 cases (2002-2008). J Am Vet Med Assoc 2010; 236: 319-325
What were the two common CT features of oral SCC in cats?
Features of SCC at sublingual and maxillary locations:
marked heterogenous contrast enhancement and osteolysis
According to endler A, Lewis JR, et al. Computed tomographic features of oral squamous cell carcinoma in cats: 18 cases (2002-2008). J Am Vet Med Assoc 2010; 236: 319-325
Do quantatitative CT features such as mass size, attenuation, LN width correlated with survival time?
No. Results of CT did not correlate with survival time.
In endler A, Lewis JR, et al. Computed tomographic features of oral squamous cell carcinoma in cats: 18 cases (2002-2008). J Am Vet Med Assoc 2010; 236: 319-325
What did CT help identify?
CT mass extension and LN enlargement.
What treatment options have shown the longest survival times with SCC cases?
Curative intent sx with radiation tx.
What is the risk of environmental tobacco smoke to cats wrt SCC?
Cats exposed to tobacco smoke seem to be at a two fold risk of developing SCC.
What is p53 protein?
The p53 protein is a tumour supressing protein that regulates cell growth and proliferation, preventing uncontrolled cell division after chromosomal damage.
True or False:
Mutations of p53 protein are common in neoplasms
True
Explain the effect of tobacco smoke on p53.
Tobacco smoke can lead to p53 mutations which results in non functional p53 protein ACCUMULATION within cells, thereby not regulating uncontrolled cell division.
Snyder LA, Bertone ER, et al. p53 expression and environmental tobacco smoke exposure in feline oral squamous cell carcinoma. Vet Pathol 2004; 41: 209-214
Showed that tumour biopsy samples from cats exposed to tobacco smoke were ____times more likely to overexpress p53 than tumours from cats not exposed to tobacco smoke.
4.5 times more likely to exress p53
How much more likely are cats that wear flea collars likely to develop oral SCC?
5.3 times more likely than those that did not wear flea collars.
How much more likely are cats that eat canned food likely to develop oral SCC?
How about cats that eat canned tuna?
- 6 times more likely(canned)
- 7 times more likely (canned tuna)
In one study of 84 cats, biopsies from the oral cavity included 11 tongue, 4 gingival, 4 mandibular, 2 maxillary, 2 tonsillar, 1 hard palate, and 1 from a unspecified oral location, for a total of 25 oral samples.
Papillomavirus was identified in ____% of these samples
8%
What protein in humans is associated with oncogenic papillomavirus?
RB (retinoblastoma) protein dysfunction – which results in the increase of p16 protein.
p16 protein is identified by increased p16 immunoreactivity. This was found in 7% of feline oral SCC tumour samples
(Munday JS, Howe L, et al. Detection of papillomaviral DNA sequences in a feline oral squamous cell carcinoma. Res Vet Sci 2009; 86: 359-361)
True or false:
Altered EGFR (epidermal growth factor rceptor) expression may play a role in development of feline oral SCC.
True
In Looper JS, Malarkey DE, et al. Epidermal growth factor receptor expression in feline oral squamous cell carcinomas. Vet Comp Oncol 2006; 4: 33-40:
What percentage of samples had positive immunoreactivity to epidermal growth factor receptor (EGFR)?
Does this expression significantly alter the outcome for the cat?
69%
No studies have been done on ORAL SCC wrt outcome when samples express EGFR. However, CUTANEOUS SCC samples that express EGFR have a significantly worse outcome.
What are three functions of COX 1
COX 1 catalyzes the synthesis of PG involved in:
|Gastric mucosa protection
vasodilation of the kidneys
synthesis of thromboxane/promotes clotting/plt aggregation
What does COX 2 activation lead to?
COX 2 activation leads to PGE2 production - which is proinflammatory
Inflammation may contribute to carcinogensis.
Are feline maxillary SCC more common in the rostral or caudal area of the maxilla?
Caudal.
True or false:
Fluorodeoxyglucose (FDG) positron emission tomography (PET)/CT has been used for staging in 12 cats with oral SCC. FDG-PET appeared to provide even better delineation of tumor margins than with CT alone
True
True or false:
- Palpation of regional lymph nodes is a good indicator of lymph node metastasis in dogs
- The sensitivity and the specificity of fine-needle aspiration cytology of mandibular lymph nodes were found to be very high in dogs.
- Pulmonary metastasis appears to common, with 15 of 16 cats showing evidence of pulmonary metastasis in one study
- Hypercalcemia may occasionally be associated with feline oral SCC
- Most neoplasms exhibit variable degrees of inflammation (neutrophils, lymphocytes, plasma cells), necrosis, ulceration, and desmoplasia.
- Invasion into the adjacent connective tissue (including nerves), skeletal muscle (in lingual neoplasms), or bone (in gingival neoplasms) is common.
- FALSE. It is a good indicator.
- TRUE
- FALSE – not common; 1/16 showed pulmonary mets in one study
- TRUE
- TRUE
- TRUE
- TRUE