Dermatology tumour surgery

Question 1

What are the benign oral tumours

Answer 1

Peripheral odontogenic fibroma
Acanthomatous ameloblastoma

Question 2

What are the malignant oral tumours; which are most common in dogs vs cats

Answer 2

Dogs: melanoma > SCC > fibrosarcoma
Cats: SCC > fibrosarcoma

Question 3

How to treat acanthomatous ameloblastoma

Answer 3

Surgery with 1cm margin

Question 4

Treatment of oral malignant melanoma

Answer 4

Often just palliative as highly metastatic
- Can do surgery for local palliative control
- Can add in vaccine, chemo, radio as adjunctives

Question 5

Treatment of oral squamouc cell cardinoma

Answer 5

Surgery +/- radiotherapy
Generally locally invasive and not very metastatic (tonsillar form may metastasise)

Question 6

Which breeds are prone to oral squamous cell carcinoma; which to oral fibrosarcoma

Answer 6

SCC = poodles, cockers
Fibrosarcoma = golden retrievers, labs

Question 7

Characteristics and treatment of oral fibrosarcoma

Answer 7

MAxilla mostly; highly invasive
~20% metastatic rate
Treat with surgery and need wide margins - want 2-3cm margin at least

Question 8

Which oral tumours are radiosensitive; which isn’t

Answer 8

Melanoma and SCC are radiosensitive
Oral fibrosarcoma is poorle responsive

Question 9

Out of maxillectomy and mandibulectomy which is most likely to give issues with bleedin and why

Answer 9

Maxillectomy because the palatine bracnhes of maxillary arteries are less accessible to ligate c/f mandibular artery

Question 10

Most op care for mandibulectomy/maxillectomy

Answer 10

Soft food 2-3 weeks
No hard chews 6-8 weeks
May need assisted feeding
Rigid elizabethan collar
Monitor for dermatitisulceration

Question 11

What nasal planum tumours are most common in dogs/cats

Answer 11

Cats: SCC&raquo_space; lymphoma…others
Dogs: SCC > adenocarcinoma

Question 12

Characteristics of nasal planum SCC in cats

Answer 12

Locally invasive
Low rate of metastasis
Related to sunlight exposure; papillomaviruses may be involved

Should check ears and eyes too

Question 13

Sugery margins for cat vs dog nasal planectomy

Answer 13

Cat = 0.5cm margins
Dogs = 2cm margin

Question 14

What suture material do we use to appose skin to nasal mucosa in nasal planectomy surgery

Answer 14

Non-absorbably; sedate and remove 2 weeks later
Because this is less inflammatory

Question 15

Why do we excise the alar fold during nasal planectomy surgery

Answer 15

To optimise airway diameter

Question 16

Post op care for nasal planectomy

Answer 16

Soft smelly food for 4-6 weeks
Elizabethan collar needed for 2 weeks
MAy need feeding tube
NSAIDs to reduce welling

Question 17

What is the most common skin tumour in dogs

Answer 17

Mast cell tumour

Question 18

What drug do we give before starting mast cell tumour surgery

Answer 18

Chlorphenamine to reduce degranulation risk

Question 19

What might we do before mast cell tumour surgery to increase chances at getting margins

Answer 19

Use steroids to shrink the tumour

Question 20

What margins do we go for with mast cell tumours; what about if on the distal limb

Answer 20

Ideally: 2-3cm margin + DEEP FASCIAL PLANE
May do ‘reasonable margin’’ for small tumours in hard location

In distal limb if confident can get a margin can leave to heal by second intention
If not DO NOT COMPROMISE CLOSURE; do marginal excision and either wait or do radiotherapy

Question 21

What qualifies as a reasonable deep fascial plane (mast cell tumour)

Answer 21

Fascia, muscle, bone
NOT FAT as not a good tumour barrier

Question 22

When do we stage mast cell tumours

Answer 22

Probably only if the tumour was high grade

Question 23

Characteristics of soft tissue sarcomas

Answer 23

Slow growing, locally invasive, low tendency for metastasis

Question 24

How to diagnose soft tissue sarcoma

Answer 24

FNA can help but only accurate in 60%; histopath better

Question 25

What margins to take on soft tissue sarcoma surgery and which type is it different for

Answer 25

2-3 cm margins + deep fascial plane

BUT for feline injection site sarcoma want a 4-5cm margin