Skin, Ears and Toes Flashcards
(122 cards)
What are the four most common skin and SQ tumors in cats?
Basal cell tumors, MCT, SCC and fibrosarcoma
Papillomaviruses are only able to replicate in _____ cells
terminally differentiated cells
What are the two main viral proteins from papillomavirus that lead to neoplastic transformation? What do that interact with?
E6 - destabalizes p53 E7 - inhibits pRB
Disruption of p53 by papillomavirus protein can cause increased levels of ____ which is detectable with IHC
p16
Canine papillomavirus has been associated with the development of ______
SCC - usually cutaneous
What are PPVs associated with in cats?
Viral plaques - aka feline sarcoids
PPV can be detected with IHC in most feline plaques - as the plaques progress to SCC, the ability to detect PPV ag increases/decreases
Decreases
PPV is detected in more UV-protected or UV exposed areas of SCC in cats
UV-protected - up to 76% vs. 42% of UV exposed
Basal cell carcinoma in people is thought to arise from critical mutations in what signaling pathway
Hedgehog
What aberrant karyotypes have been found in feline basal cell tumors
Trisomy E2 and monosomy E2 - unknown significance
____ staining is considered fairly specific for human BCC and was detected in 23/24 BCC in cats in one study
Bcl-2
The presence of detectable ____ with IHC indicates mutations in the coding sequence and has been associated with what cutaneous tumor in cats and dogs
p53; SCC
What does p27 do? What cancer type has lower levels of this compared to benign tumors?
protein thought important in maintaining cells in G0 SCC
Nuclear activation of beta-catenin was detected in 100% of what skin tumor(s)
trichoepitheliomas and pilomatricomas
Which cyclin is expressed in the majority of feline SCC and just under half of canine SCCs
cyclin A
What is the causative mutation causing renal cystadenoma and nodular dermatofibrosis?
Birt-Hogg-Dube (BHD) gene
What does the BHD gene code for?
Tumor suppressor protein folliculin
What TKI has been associated with the rapid development of actinic keratosis and invasive SCC in people? What does this TKI inhibit?
Sorafenib - inhibitor of RAF and VEGF/PDGFR
What markers are used to differentiate BCC from SCC in people
epithelial membrane protein BerEP4
What dog breeds are at an increased risk for BCC
cocker spaniels, poodles
What are the three histologic subtypes of BCC in dogs
solid, keratinizing and clear cell
What is the behavior of BCC in dogs?
Low-grade malignancy; can recur but no reports of mets
Where does BCC most commonly occur on cats?
Head and neck - can be pigmented, too!
In patients with multiple papillomas, what drug may be effective
azithromycin