Exam 1 - GI Neoplasia

Question 1

what is the most common perianal tumor of the dog? second & third most common?

Answer 1

perianal adenoma - 75%, benign

anal sac adenocarcinoma - 20%

perianal adenocarcinoma - 5%

Question 2

what are some uncommon perianal tumors in the dog?

Answer 2

mast cell tumors, SCC, & melanoma

Question 3

why are perianal adenomas most commonly seen in intact males? what do they arise from?

Answer 3

they are testosterone dependent tumors that arise from the sebaceous cells in the perianal area

Question 4

where are perianal ademonas commonly located?

Answer 4

superficial hairless skin around perineum

Question 5

what is the metastasis like in perianal adenocarcinoma? where are the most likely going to met to?

Answer 5

reported in up 50% - especially after multiple recurrences

medial iliac lymph nodes

Question 6

why did we see high rates of metastasis in anal sac adenocarcinomas in the 90s? why do we not see that high of a rate now?

Answer 6

rectal exams weren’t a normal part of a physical exam, so metastasis was reported at 60-96% (end stage disease when diagnosed)

we started doing rectal exams

Question 7

what are some important questions do you need to ask for perianal tumors?

Answer 7

patient signalment, location of the mass, slow vs. fast growing mass, painful/ulcerated mass, tenesmus, PU/PD (is calcium playing a role - paraneoplastic syndrome in AGASACA)

Question 8

why may you see tenesmus in an animal with a perianal tumor?

Answer 8

high risk of mets - if you have big lymph nodes, may press on the colon

impacted anal gland on top of tumor, mass blocking the tumor

Question 9

T/F: spayed female dogs can get perianal adenomas

Answer 9

true - rare

Question 10

are perianal adenocarcinomas common or rare? what do they arise from?

Answer 10

rare - sebaceous cells in the perianal region

Question 11

where are perianal adenomas commonly located?

Answer 11

superficial hairless skin around perineum

Question 12

what do anal sac adenocarcinomas arise from?

Answer 12

apocrine sweat gland cells of the anal sacs - usually single mass, rarely bilateral, very locally invasive

Question 13

T/F: there is no breed or sex predilection for anal sac adenocarcinomas

Answer 13

true

Question 14

what kind of mass do you think this is?

Answer 14

perianal adenocarcinoma

Question 15

what perianal tumor type is associated with hypercalcemia of malignancy? what should stick out in the history as a result?

Answer 15

AGASACA - animal will be PU/PD

Question 16

what is the treatment of choice for perianal adenomas?

Answer 16

castration - most tumors will regress over months

Question 17

what is the prognosis for perianal adenomas?

Answer 17

excellent

Question 18

when is conservative surgical excision indicated for perianal adenomas?

Answer 18

ulcerated masses & recurrent masses

Question 19

what treatment is recommended for large, diffuse lesions of perianal adenomas?

Answer 19

allow time for regression to allow for safer surgical excision if necessary

Question 20

what is the treatment of choice for perianal adenocarcinomas?

Answer 20

wide surgical excision & lymph node extirpation of lymph node mets

Question 21

what staging is indicated for perianal adenocarcinomas?

Answer 21

abdomen/pelvis CT or ultrasound

chest rads

Question 22

when is radiation or chemo used for perianal adenocarcinomas?

Answer 22

radiation - post-op setting to prevent recurrence

chemo for inoperable tumors

Question 23

what is the prognosis for perianal adenocarcinoma?

Answer 23

fair to good, <5cm is prognostic

Question 24

what is the biologic behavior of anal sac adenocarcinoma?

Answer 24

locally invasive tumor that is typically one-sided

can be small in size with marked metastatic disease

Question 25

what is the most common site of metastasis for anal sac adenocarcinomas?

Answer 25

regional lymph nodes - sub iliac other sites - lungs, liver, spleen, & bone

Question 26

T/F: genitourinary tumors have an increased risk for bone mets

Answer 26

true

Question 27

why do we see hypercalcemia of malignancy in AGASACA?

Answer 27

in about 25% of cases PTHrP secreted by the tumor causing hypercalcemia - only clinically evident with bulky disease

Question 28

what are some clinical signs associated with primary AGASACA?

Answer 28

scooting, perianal discomfort, & bleeding

Question 29

what are some signs associated with lymph node metastasis in animals with AGASACA?

Answer 29

tenesmus & constipation

Question 30

what clinical signs are attributed to hypercalcemia in animals with AGASACA?

Answer 30

PU/PD, anorexia, lethargy, & muscle spasms in severe cases

Question 31

what staging is done for a primary tumor of AGASACA?

Answer 31

FNA & cytology

Question 32

what staging is done for lymph node metastasis in AGASACA?

Answer 32

advanced imaging - abdominal ultrasound or abdominal rads

Question 33

what staging is needed for distant metastasis in AGASACA?

Answer 33

chest rads or thoracic CT

Question 34

what staging is needed for an animal with hypercalcemia due to AGASACA?

Answer 34

CBC/chem/UA, ionized calcium, & hypercalcemia panel

Question 35

what are the benefits of using a CT for staging?

Answer 35

complete regional lymph node evaluation!!!! surgical planning for primary tumor +/- lymph nodes radiation planning good bone detail to evaluate for bony mets evaluate liver & spleen

Question 36

T/F: stage of disease with AGASACA dictates the treatment & prognosis

Answer 36

true

Question 37

what is the treatment indicated for a primary tumor of AGASACA?

Answer 37

wide surgical excision - always but it is an incomplete excision always because it is an anal sac tumor

Question 38

what complications are associated with removed a primary tumor of AGASACA?

Answer 38

low risk but fecal incontinence

Question 39

what surgery is recommended for AGASACA is there is lymph node metastasis? what complications are associated with it?

Answer 39

lymph node extirpation complications depend on extent of metastasis - hemorrhage & damage to vital structures

Question 40

what are some acute side effects associated with radiation for AGASACA?

Answer 40

moist desquamation colitis transient fecal incontinence

Question 41

what are some chronic side effects associated with radiation for AGASACA?

Answer 41

chronic colitis, rectal/colonic stricture, & rectal/colonic perforation

Question 42

when is radiation used for a primary tumor of AGASACA?

Answer 42

definitive therapy post-op to prevent recurrence, may be used pre-op, & palliative for advanced disease

Question 43

when is radiation used for lymph node metastasis of AGASACA?

Answer 43

definitive radiation therapy to treat draining regional lymph nodes (metastatic or prophylactic setting) or palliative for advanced disease

Question 44

why is radiation used for a hypercalcemia associated with AGASACA?

Answer 44

may improve the hypercalcemia - use steroids & bisphosphonates concurrently

Question 45

T/F: chemotherapy is generally ineffective for local tumors of AGASACA

Answer 45

true

Question 46

when is chemo used for AGASACA?

Answer 46

used to address metastatic disease in lymph nodes & distant metastasis may help improve hypercalcemia - use steroids & bisphosphonates concurrently

Question 47

what cytotoxic chemotherapy is used for AGASACA?

Answer 47

mitoxantrone, carboplatin recommended 1st line chemo especially in an adjuvant microscopic disease setting

Question 48

what targeted chemotherapy is used for AGASACA?

Answer 48

palladia (toceranib) - used in gross disease setting

Question 49

T/F: multi-modal therapy for AGASACA improved survival times for ALL stages

Answer 49

true

Question 50

what is the MST of AGASACA when surgery, radiation, & chemo are used?

Answer 50

>900 days

Question 51

what characteristics represent early stage AGASACA?

Answer 51

<3.2cm & no mets

Question 52

what is the MST for early stage AGASACA using surgery alone? what was seen after?

Answer 52

1200 days 30-50% developed recurrence & mets 1-2 years later

Question 53

what is the MST for AGASACA with a large primary tumor & regional lymph node metastasis?

Answer 53

surgery - 180 days hypofractionated RT - 450 days

Question 54

what is the prognosis of AGASACA with distant mets?

Answer 54

poor to guarded slow growing, so better than other tumors

Question 55

______ _________ with routine rectal exams is key for prognosis of AGASACA

Answer 55

early detection

Question 56

T/F: cats get perianal adenomas, perianal adenocarcinomas, & anal sac adenocarcinomas

Answer 56

false - they don't get perianal adenomas or perianal adenocarcinomas

Question 57

what perianal tumors do cats get?

Answer 57

anal sac adenocarcinomas - RARE