oncology exam 2 Flashcards
What is the #1 oral tumor in dogs, other 2 MC oral tumors?
1= MELANOMA
#2= SCC #3= fibrosarcoma
What is the #1 oral tumor in cats, other MC oral tumor?
1-SCC!!!
2- fibrosarcoma
Is an odontogenic tumor malignant or benign?
benign
What type of biopsy is preferred for proliferative oral tumors?
shave biopsy
True or false- to save time you should just biopsy an oral mass through the lip?
NO- WHY IN THE ACTUAL FUCK WOULD YOU DO THIS?
True or false- you should take two thoracic rads to check for mets from oral tumors?
false- take 3
Which of the following is false about malignant oral melanomas?
A. the non-pigmented variant is amelanotic melanoma and you can do special stains for Melan A
B. these tumors are malignant, but don’t generally result in mets
C. surgery results in local control
D. thorough staging is required
B- these tumors are malignant but they can form systemic mets in about 80% of animals, biggest point of treatment failure
True/false- oral fibrosarcomas are histologically low grade, therefore we don’t really need to worry about them?
Falsomundo- they are histologically low grade but they can be biologically high grade
-if biopsy comes back as fibroma don’t believe it
this type of tumor generally effects younger (7-8 yr) goldens and labs, and has relatively low met rate, BUT recurrent disease after surgery tends to be the biggest point of treatment failure
Tell me about oral SCC in dogs…
- locally invasive
- low rate of metastasis (<20%)
Where do oral SCC prefer to live in cats?
-sublingual site
these are locally invasive
risk factors= flea collar usage, smoke exposure, excessive canned food (esp tuna)
-increased PTHrp which can lead to bone resorption and hypercalcemia
Which type of odontogenic tumor is locally invasive into bone and needs very aggressive local surgery for control?
-ancanthomatous ameloblastoma- sheepdogs are overrepressented, rostral mandible is most common
Which is pretty much the feline equivalent of an ameloblastoma?
feline inductive odontogenic tumor
- locally invasive, no
metastasis
-tx like ameloblastoma
What is the gold standard treatment for oral tumors?
- aggressive surgical excision- almost always bone involvement (except peripheral odontogenic fibromas)
- need to have 2 cm margins for most
- more rostral= easier to excise, better px
Which types of oral tumors are responsive to radiation?
MELANOMA, SCC (dogs), acanthomatous ameloblastoma. and FSA
When would you consider chemotherapy for oral tumors?
- if tumor considered highly metastatic
- piroxicam- sublingual SCC in cats
- MELANOMA= NOT CHEMO RESPONSIVE
What is the MC gastric tumor in dogs? Second MC?
1- adenocarcinoma
2-leiomyosarcoma/leiomyoma
MC gastric tumor in cats?
lymphoma
What is the predilection site for gastric ACA?
- pyloric antrum/ lesser curvature
- HAS A HIGH METASTATIC RATE- 75%
What diagnostic modalities are preferred for gastric tumors?
- abdominal ultrasound
- U.S. guided FNA/cytology
- endoscopy- assess resectability
Recommended treatment for gastric tumors?
-surgical excision
Which of the following has the worst prognosis?
Leiomyosarcoma, LSA, ACA
ACA- most dead within 6 months, can have better px if no mets and resectable
LSA- doesn’t respond well to chemo, can resect
Leiomyosarcoma- MST- 12-21 mo, metastasis- not poor px factor
px depends on surgical excision, tumor type/grade, presence of mets
Which animal is more susceptible to large intestinal tumors? small intestinal tumors?
- LI tumors= dogs- collie and GSD, male sex predilection
- SI- cats
How do we diagnose intestinal tumors?
- US guided FNA/cytology- relatively high diagnostic accuracy- should attempt in all cases
- endoscopy can be used but will not provide access to jejunum and proximal ileum- careful in cats because MC location is ileum
- goal is to rule out LSA
What is the top ddx for intestinal tumors in dogs and cats?
LSA!
ACA is the second most common in both
third most common in dogs: leiomyosarcoma
third most common in cats: MCT
Treatment for intestinal tumors
-surgery- exception is LSA because it’s usually too diffuse
- take wide margins (4-8 cm)
- mesenteric and regional lymph nodes should be assessed, resected, and aspirated (if not amenable to excision)
MST for intestinal LSA
- dogs- 77 d, negative prognostic indicators= didn’t achieve remission or diarrhea at presentation
- cats- MST- 201-280 days, px indicator= response to chemo/tx
MST- intestinal ACA
- dogs- MST= 272-300 days, female= worse px
- cats- majority are advanced with 72% metastatic rate at dx
- MST= 5-15 mo
intestinal MCT- prognostic factors
- dogs= VERY BAD, 16 day MST
- cats= solitary intestinal MCT without mets may have prolonged survival following complete surgical excision
intestinal MCT- leiomyosarcoma
-dogs: 8 months after surgical resection
Gastrointestinal stromal tumor
- express c-kit on IHC
- predilection for cecum
- MST= 11.6 months, if survive sx= 37.4 months
- many die due to septic peritonitis because masses rupture before diagnosis
Most common chest wall tumors in dogs (in order of prevalance)
- OSA, CSA
Treatment of chest wall tumors
- en bloc excision with chest wall reconstruction (max rib excision=6)
- can do prosthetic mesh augmentation depending on size and location of defect
- adjunctive chemotherapy recommended for OSA
prognosis for chest wall tumors
-MST= 120 days for OSA following chest resection alone
MST- 240 days OSA - chest wall resection and chemo
MST= 299-1080 days with CSA
-tumor type and complete histologic resection play role
Which syndrome is unique to cats with lung tumors?
- lung-digit syndrome= LAMENESS
- mets to toes–> weight bearing digits and third phalynx
- always do chest rads when you see this
Most common lung tumors in dogs
carcinomas
- bronchoalveolar ACA= MC
- SCC= uncommon
-others= histiocytic sarcoma (often multiple pulmonary masses)
most common lung tumors- cats
-bronchial adenocarcinoma
What is the best diagnostic tool for lung tumors in both dogs and cats?
-transthoracic FNA/cytology
What is a major negative prognostic factor for lung tumors?
-tracheobronchial lymph node enlargement
Treatment of lung tumors
- lateral thoracotomy for small to medium lung tumors–> hilar ln biopsy (even if small on ct)
- partial lobectomy= okay, complete=preferred
Lung tumor prognostic factors- dog
- tumor size= small <5 cm
- location= more peripheral is better
- clinical signs at time of diagnosis- 240 days with c.s.- 545 without
- clinical stage- T1 (solitary)- 26 months, T2= multiple (7 months), T3- invasion into adjacent tissue (3 mo)
- histiologic score- 790 days if well differentiated, 25 days if moderately differentiated, 5 days if poorly differentiated
- 1 month with lymph node involvement vs 15 mo
- MST= 8 m with SCC, 19 mo with ACA
lung tumor prognostic factors- cat
- histiologic grade= most important
- poorly differentiated- MST=2.5 m
- well differentiated- MST= 23 months
- presence of pleural effusion= negative
What is a common concurrent condition with thymoma?
- Paraneoplastic syndrome- 67% thymomas
- myasthenia gravis
- erythema multiforme
- hypercalcemia
- T-cell lymphocytosis
- anemia
- polymyositis
Most common cranial mediastinal tumor
-lymphosarcoma- thymoma is second
Diagnosis of thymoma
- may have mass effect on thoracic rads
- FNA/cytology- large numbers of mature lymphocytes
- send out flow cytometry
Treatment of thymoma
- surgical treatment= gold standard
- radiation if not amenable to surgery
- chemo is usually ineffective
thymoma- prognosis for dogs
- good overall
- surgical excision- MST= 790 days
- radiation- MST= 248 days
- poor prognostic factors: younger, megaesophagus, lymphocyte rich variants= better
thymoma- prognosis for cats
- excellent overall
- sx excision, MST= 1,825 days
- radiation= MST= 720 days
What is the most common primary bone tumor of dogs and cats?
OSTEOSARCOMA
- 85% bone tumors in dogs
-second MC= chondrosarcoma
Signalment of OSA in dogs
- large to giant breed dogs- size and height prognostic
- early gonadectomized Rotties (<1 yr)
- breeds MC= great danes, irish wolfhounds, greyhounds, rotties, scottish deerhounds, St. bernards
proposed etx of osteosarcoma
- hormonal
- genetic
- repetitive microtrauma
- molecular factors- protooncogenes- MET, Tropomyosin-related kinase, HER 2
- insulin like GF
- telomerase
How can you differentiate osteosarcoma from infectious causes of lameness like “valley fever”
-if infectious usually systemically ill
Where is the predilection site for osteosarcomas? Dogs and cats?
- appendicular skeleton
- dogs: forelimbs 2x more than pelvic limb, distal radius and then proximal humerus are MC sites, favor metaphyseal region
- cats- pelvic limb, favor diaphysis
True/False OSA are known for crossing the joints?
False
What is the preferred diagnostic modality for OSA?
- FNA/cytology
- can do biopsy but it’s then difficult to do limb sparing procedure
-biopsy needles- Jam Shedi, Michele trephine- higher risk of pathological fracture
What is the gold standard for local management of primary bone tumors?
-limb amputation
Your dog is extremely obese making him a poor candidate for amputation, his tumor is located on the humerus, does this make him a better or worse candidate for limb salvage?
-worse- distal radius is the preferred site for limb salvage procedure