Endocrine Tumours Flashcards
What’s the distribution of canine pituitary adenoma, invasive adenoma, and adenocarcinoma on necropsy?
61% = adenoma
33% = invasive adenoma
6% = adenocarcioma
What % of dogs will not have a visible pituitary mass on CT or MRI when they are first diagnosed with PDH?
40-50%
What % of dogs will have a visible pituitary mass on CT or MRI when they are first diagnosed with PDH?
15-25%
Are there any commercially available diagnostic tests that can predict a PDH patient’s risk at developing neurological signs in dogs?
No.
The pro-opiomelanocortin/pro-ACTH levels are correlated to pituitary gland size in dogs with PDH but this is not commercially available
What’s the MOA of trilostane?
It’s a corticosteroid analog that inhibits 3-beta-hydroxysteroid –> essential for the production of cortisol and other steroids
What’s the MOA of pasireotide?
It’s a somatostatin receptor analog that has shown some efficacy in decreasing the pituitary tumour volume, improving ACTH concentration, urine creatinine:cortisol, and clinical signs
- AE: diabetes mellitus
- very expensive
What medications that can improve the “dopamine tone” has been used for canine PDH with some efficacy?
- selegiline
- cabergoline
What pituitary height to brain ratio would be considered to have a pituitary macroadenoma in dogs?
> 0.31
What’s the outcome of transsphenoidal hypophysectomy for dogs with pituitary tumours?
- periop survival = 91%
- MST = 781 days (~2y)
- median DFI = 951 days (~2.5y)
- Recurrence rate = 27%
- median time to recurrence = 555d (~1.5y)
- will need lifelong thyroid and glucocorticoid supplement, and desmopressin short term or long term
What’s the outcome reported in a prospective study in dogs with PDH treated with transsphenoidal hypophysectomy?
Success rate ~65%
- 12/150 (8%) died post-op
- 127/150 (85%) remission
- 32/150 (21%) recurrence
What are some surgical complications of transsphenoidal hypophysectomy in dogs?
- hemorrhage
- electrolyte imbalance
- neurological deficits
- decreased tear production
- thromboembolic disease
- recurrent PDH
- perioperative death
What’s the general outcome of RT for PDH in dogs?
- 2 to 3.8y
- smaller tumours had better outcome
- effective at controlling the neurological signs
- variable outcome for the Cushing’s aspect
What % of dogs/ cats will have HAC due to PDH?
80-85%
What’s the outcome of transsphenoidal hypophysectomy in cats with PDH?
-2/7 (29%) died within 4 weeks of surgery
- 2/7 (29%) died several months after the surgery
- 1/7 (14%) was in remission for 19 months
What are some surgical complications of transsphenoidal hypophysectomy in dogs?
- hypopituitarism (short or long term)
- electrolyte imbalance
- soft palate dehiscence
- reduced tear production
What’s the outcome of RT for feline PDH?
unclear how it manages the endocrine disease
What’s the medical treatment of choice for feline PDH?
trilostane
What’s the likelihood of acromegaly in cats?
- 10-15% of diabetic cats
- up to 30% of hard-to-control diabetic cats
What’s mechanism of insulin resistance in cats with acromegaly?
- due to GH-induced post-receptor defect in the action of insulin on target cells
- these cats keep on gaining weight! (opposite of a typical diabetic cats)
What’s the blood test that can be used to diagnose acromegaly?
- serum insulin-like growth factor 1 (IGF-1)
- sensitivity = 84%; specificity = 92%
- there can be some overlap with uncontrolled diabetic cats
Is serum IGF-1 concentration reflective of diabetic control for feline acromegaly treated with RT?
No, serum IGF-1 concentration doesn’t appear to correlate with improved diabetic control
What’s the outcome of surgery for acromegaly?
- only a few published cases
- 3/21 died post-op
- remaining 18 had reduction in IGF-1
- 14 achieved diabetic remission
What’s the outcome of SRT for feline acromegaly?
MST = 1072d (2.9y)
- no association noted between tumor size or serum IGF-1 concentration and survival
- 10 had acute RT side effects –> pred resolved issues
- 7/50 had hypothyroidism months to years post
- 39/41 reduced insulin dose
- 13/41 (32%) went into diabetic remission
What are some options for medical therapy for feline acromegaly?
- octreotide –> unsure of long term outcome
- pasireotide –> encouraging, but expensive and causes diarrhea
What’s the outcome of feline acromegaly treated with insulin only (for the diabetes)?
MST = 20.5m
- Patients may succumb to cardiac or renal failure, neurologic disease, or complications of poorly regulated diabetes mellitus
Does mineralization of the adrenal gland indicate malignancy?
no
What’s the sensitivity and specificity to detection adrenal tumour invasion into the caudal vena cava based on U/S? CT?
U/S:
Sensitivity = 80-100%
Specificity: 90%
CT:
Sensitivity = 92%
Specificity: 100%
What’s a general size cut off of canine adrenal glands that would indicate malignancy?
> 2cm
What’s the metastatic rate of canine adrenocortical carcinoma?
50%
Where are the most common locations for metastasis for canine adrenocortical carcinoma?
liver and lungs
What’s the likelihood of vascular invasion into phrenicoabdominal vein/ renal vein/ caudal vena cava for canine adrenocortical carcinoma?
20%
What’s one characteristic of dogs with ADH that is different than those with PDH?
The majority of dogs with ADH >20kg
What would be diagnostic test of choice for ADH?
LDDST,
ACTH stim only has 60% sensitivity for diagnosing ADH
What’s the thickness of the contralateral adrenal gland in dogs to be consistent with ADH?
<5mm
What’s the outcome of adrenalectomy for canine adrenocortical carcinoma?
MST = 230-778d (~0.5-2y)
- adenoma MST - 688d (1.8y)
- can be good if survives the post-op period
- mean ST = 3y
- 29/144 (20%) died during surgery or immediate post-op
What’s the outcome for canine adrenocortical tumours treated with SRT?
in a small case series of 9 dogs:
- 6 = non secretory
MST = 1030d (2.8y)
What are some medical treatment options for ADH?
mitotane (cytotoxic) or trilostane
- MST is similar, worse if metastasis is present
- Mitotane: 3.5-15.6m
- Trilostane: 12-15m
What’s a key feature of aldosterone-secreting adrenal tumour on serum biochem?
hypokalemia
What’s the most common adrenocortical disorder in cats?
Hyperaldosteronism (aka primary aldosteronism or Conn’s syndrome)
What are some clinical signs of Conn’s syndrome?
- muscle weakness from hypokalemia
- arterial hypertension/ ocular changes
- hypernatremia usually not present due to intact water balance mechanism
- concurrent renal disease
What’s one test that has been shown to be useful in diagnosing feline hyperaldosteronism?
oral fludrocortisone suppression test
How is primary aldosteronism treated in cats?
- Surgery if unilateral - has good outcome
- if no surgery, medical management with potassium supplementation, spironolactone, and antihypertensive drugs can give reasonable ST
What’s the metastatic rate of pheochromocytoma in dogs?
up to 40%
What’s the rate of caudal vena cava invasion in canine pheochromocytoma?
up to 82%
What are the most common metastatic sites of pheochromocytoma?
liver, spleen, lungs, regional lymph nodes, bones, and CNS
Which IHC can be used for diagnosing pheochromocytoma?
chromogranin-A
Which blood test can be used to diagnose pheochromocytoma?
normetanephrine (in urine or blood)
What’s the outcome adrenalectomy for pheochormocytoma?
if survive the peri-op period, MST = 374d
What’s the outcome of SRT for canine pheochromocytoma?
5/8 dogs were alive at the time of follow up, with a median follow up time of 25.8 months (>2y)
What’s the mortality rate of adrenalectomy in dogs?
15-37%
What are some prognostics factors for adrenalectomy in dogs?
- presence/ size of thrombus
- concurrent nephrectomy
- blood transfusion
- tumour type
- tumour size (>5cm)
What medical therapy is needed for patients with ADH post adrenalectomy in dogs?
supraphysiologic dose of prednisone post-op, tapered off over several weeks
- good to perform TEG and ACTH stim, too
What’s the outcome of adrenalectomy in cats?
- MST = 50 weeks (just under a year)
- 70% survived >2week post-op
- Laparoscopic: MST = 803d (2.2y)
What’s the outcome for cats with Conn’s syndrome treated with adrenalectomy?
MST = 1297d (3.5y)
What’s a suggested protocol for monitoring incidentaloma?
If the mass is <2cm and there is concurrent endocrine abnormalities, then repeat U/S every 3m
- need to make sure this is not an adrenal met!
When should adrenalectomy be considered for incidentaloma?
- > 2.5cm
- locally invasive
- functional
What type of thyroid carcinoma is more common in the dog? what’s the significance?
- Follicular thyroid carcinoma is more common in the dog
- Medullary thyroid carcinoma is thought to be less metastatic
- more of a human thing –> this distinction is rarely used clinically
How good is U/S for diagnosing thyroid carcinoma?
- it’s a good screening tool
- but not as good as CT or MRI for determining the invasiveness or thyroid origin
What are the most common places for thyroid carcinoma to spread to?
- Regional LNs (including the mandibulars!)
- lungs
- abdominal organs
What’s a good way to assess the invasiveness of a thyroid carcinoma?
CT scan!
- it’s better than palpation
- if it looks round/ovoid & mobile then likely noninvasive
What are some potential complications of surgery for thyroid carcinoma?
- hemorrhage
- damage to the recurrent laryngeal nerve/ laryngeal paralysis
Is bilateral thyroid carcinoma worse (in terms of ST) than unilateral thyroid carcinoma?
- the ST after surgery is comparable between total thyroidectomy and unilateral thyroidecotmy
What medical therapy may be required for dogs undergoing total thyroidecotmy?
- if the parathyroid gland is not preserved, need to monitor for hypocalcemia and supplement as needed
- not all dogs with post-op hypocalcemia will need long-term supplementation
What’s the outcome of radiation therapy for invasive thyroid carcinoma in dogs?
- hypofractionated protocol = 96 weeks (1.8y)
- definitive intent = 24.5m
- palliative = 170d (6m)
Is pulmonary metastasis a negative prognostic factor for canine thyroid carcinoma treated with RT?
no!
What endocrine abnormalities can occur after RT for canine thyroid carcinoma?
hypothyroidism
What’s the outcome of dogs with invasive thyroid carcinoma treated with I131?
- good!
- if based on scintigraphy and body (+/- surgery), MST = 30m (2.5y)
- if based on emprical dosing = 34m (~3y)
- if using really high dose, fatal bone marrow suppression is possible
- those with metastasis = 366 d (1y) vs 839 d (2.3y) without metastasis
What’s an advantage of I131 or RT?
I131 can also target metastatic disease
(RT is can offer even dose distribution within the tumour)
What’s the general outcome of dogs with unilateral, mobile, thyroid carcinoma treated with thyroidecotmy?
- good!
36m (3y)
What are some features of canine thyroid carcinoma likely means higher risk of metastasis?
- large tumour size (diameter and volume)
- bilateral
What are some features of canine thyroid carcinoma likely means shorter disease free interval?
gross and histological evidence of vascular invasion
What’s the role of chemotherapy for dogs with surgically removed thyroid carcinoma?
- undefined
- one study did not find improved ST after surgery
- carboplatin is the chemo choice
What’s the outcome of canine metastatic thyroid carcinoma treated with Palladia?
- 12/15 dogs had a benefit: 4 PR and 8 SD
(wasn’t used as first line treatment) - can be considered for metastatic disease
What are some medical management options for canine thyroid carcinoma that Sx, RT or I131 can’t be done?
- methimazole
- iodine-restricted diet
What’s the thyroid status of dogs with thyroid carcinoma?
- 50‐60% of affected dogs are euthyroid
- 30‐40% are hypothyroid,
- 10‐20% are hyperthyroid
What’s the metastatic rate of canine thyroid carcinoma on presentation?
8-16‐38%
How common in bilateral thyroid carcinoma in dogs?
9%
What’s the most common thyroid tumour associated with hyperthyroidism in cats?
- thyroid adenoma
- malignant thyroid carcinoma only in 1-3% of cats with hyperthyroidism
How common is bilateral involvement in feline thyroid adnoma?
70-90% of cases
How common is metastasis on presentation for feline thyroid carcinoma and what’s the most common metastatic sites?
- 70%
- regional LNs and lungs
What’s the most likely environmental contributor t0 (increase) in feline hyperthyroidism?
- consumption of canned cat food
- many others are reported, but inconsistent/ contradictory
- ex: iodine content of cat food, indoor residence, use of cat litter, exposure to brominated flame retardants, and use of flea-control products
How is hyperthyroidism diagnosed in cats?
- elevated tT4
- if clinical signs present but tT4 is normal/ high normal, can follow up with free T4
- fT4 should never be used alone as cats with nonthyroid illness can have elevated fT4
- suppression tests (T3) or stimulation test (TSH, TRH), or scintigraphy
Can scintigraphy distinguish between malignant and benign thyroid tumours in cats?
no
What’s the most common medical therapy for feline hyperthyroidism?
Methimazole (carbimazole in Europe, which is converted to methimazole in the body)
How often to cats experience adverse effects to methimazole/ carbimazole? What are those signs?
10-25%
- GI (anorexia, vomiting, diarrhea) –> can try dermal formulation instead, but usually self limiting
- facial excoriation
- hepatotoxicity
- bleeding diatheses
- bloody diathesis (esp in the 1st 3 months)
What’s a potential long term disadvantage of medical therapy for feline hyperthyroidism?
Methimazole/ carbimazole are not cytotoxic. The nodules will continue to grow and it will become more difficult to control, and may be less responsive to I131.
What dietary management is available for hyperthyroid cats? what’s a potential disadvantage?
Hills y/d –> ultra low iodine diet.
- cat will need to be fed on it exclusively, even a small amount of treats, flavored meds can negate its benefits
- also no cytotoxic, no long-term study on the theoretical concerns of increased malignancy overtime
- not sure how this will affect I131
What are some definitive treatment options for feline hyperthyroidisim?
Surgery (extracapsular or intracapsular)
I 131 radiotherapy
What should be done prior to surgery for feline hyperthyroidism to determine the surgical dose?
Scintigraphy need to be performed to determine if it’s unilateral vs bilateral
(patient also need to be stabilized prior to GA, with meds and Beta-adrenergic blockers)
What’s the most common intra-op complications for feline hyperthyroidism?
cardiac dysrhythmia
What’s the most common post-op complication of feline hyperthyroidism?
6-15% will have hypocalcemia
(Horner’s and laryngeal paralysis = rare)
What’s the outcome of cats with thyroid carcinoma undergoing thyroidectomy?
Initially good with resolution of clinical signs, but may remain hyperthyroid or develop recurrent hyperthyroidism within a few months after surgery
What are some indications of I131?
- it’s is definitive treatment for feline hyperthyroidism
- thyroid carcinoma
- ectopic hyperplastic thyroid tissue
- bilateral thyroid hyperplasia
What’s the MOA of I131?
Radioactive iodine emits beta and gamma radiation
- beta irradiation accounts for 80% of the tissue damage
- only travels max 2mm in tissue –> good for local destruction
What’s the outcome of I131?
- <5% will have persistent or recurrence of hyperthyroidism
MST = 2-4y
most common cause of death/ euthanasia = cancer or renal disease
What’s one potential complication of I131 treatment?
Hypothyroidism
ST is significant less for cats who develop hypothyroidism with azotemia (compared to nonazotemic cats)
What are some risk factors for developing hypothyroidism post I131?
maybe a higher dose (4mCi vs 2mCi)
What’s the dose of I131 for thyroid carcinoma in cats?
20-30mCi (that’s >10x the typical dose!)
How can cats with thyroid carcinoma be more effectively treated with I131?
Have a combination of surgery followed by I131 –> remove the thyroid cysts
What are some alternative treatments for feline hyperthyroidism?
- U/S guided ethanol ablation –> ok for unilateral, not to be used with bilateral disease
- solitary adenoma can have good response –> resolution of c/s >12m
- U/S guided percutaneous heat ablation –> not effective long term
How does the development of azotemia influence ST for hyperthyroid cats treated with I131?
- one study didn’t show a significant decrease in ST
- but this is the same group that found the ST to be shorter if the cat becomes hypothyroid and azotemic
How common is parathyroid tumours in dogs and cats?
uncommon in dogs
rare in cats
What’s the most likely tumour type for primary hyperparathyroidism?
90% of cats/ dogs will have solitary mass –>
adenoma
- metastasis = extremely rare
- if there are 4 hyperplastic masses –> need to look for secondary hyperparathyroidism
What’s the main function of the parathyroid gland?
Calcium metabolism through parathyroid hormone (PTH)
- increases Ca2+ from bones, kidneys and intestines, mediated by vitamin D
Which breed is predisposed to primary parathyroidism?
keeshond dog
- autosomal dominant fashion, causative gene not identified
What’s the most common c/s for dogs with hyperparathyrodism?
lower urinary tract issues
- urolithiasis or UTI
What are some clinical signs of hypercalcemia?
- PU/PD
- decreased appetite/ anorexia
- weakness, lethargy
- weight loss
- muscle wasting
- trembling
- vomiting
Would the parathyroid gland be palpable with hyperparathyroidism?
- reported in some cats
- extremely rare finding in dogs
How often is PTH normal for dogs with hypercalcemia?
73%!
What could be a differentiating factor on serum biochemistry for primary parathyroidism induced hypercalcemia vs vitamin D or renal failure?
phosphorus!
In primary hyperparathyroidism, the phosphorus level should be low, but it would be high with vitamin D toxicosis and renal failure
Which imaging modality is commonly used for detecting parathyroid nodules?
ultrasound
What’s the risk of AKI in patients with primary hyperparathyroidism?
low!
- 95% of dogs will have BUN and creatinine WNL
- most of the time the increase in calcium takes time to progress and patients are not presented on emergency
What biochem value would indicate an increased risk of mineralization for a patient with hypercalcemia?
phosphorus x calcium > 70
What’s the cause of PU/PD in primary hyperparathyroidism?
secondary nephrogenic diabetes insipidus (kidneys become resistant to the effects of ADH)
What’s the definitive therapy for primary hyperparathyroidism?
surgery
How many lobes are there for a normal parathyroid?
4 –> 2 internal and 2 external
- 2 are in close proximity to the thyroid gland
- they are small, disc shaped, distinct from the thyroid glands
How should post-op hypocalcemia be treated?
- Calcium level should be measured twice daily for 5-7d post-op
- if total Ca is < 8-9 mg/dL or Ca2+ is < 0.8-0.9 mmol/L
- or if there are signs of tetany
- use IV calcium salt for acute setting (No SQ)
- Calcium or vitamin D PO can be used in subacute/ chronic setting
How is hypoparathyroidism treated?
1,25-dihydroxyvitamin D3 (Calcitriol)
- rapid onset and short-acting
- use oral vitamin D instead of oral calcium supplement to avoid risk of hypercalcemia
How does the pre-op calcium level influence the risk of post-op hypocalcemia?
one study found a the higher the calcium level pre-op, the lower the post-op calcium level.
- other studies did not find correlation between pre-op calcium and PTH level and post-op hypocalcemia
What’s hungry bone syndrome?
When the bones are so aggressively, unregulated taking up calcium that calcium supplementation fails to improve serum calcium level
What should be the goal of the calcium level post-op?
barely below the normal level, rather than WNL to avoid hypercalcemia
What are the reasons for persistent hypercalcemia after surgical removal of a parathyroid gland?
- nodule in another gland
- ectopic hyperplastic or neoplastic parathyroid nodule
- can use imaging to find, but since it’s small so can be difficult
What’s the % of calcium control after surgery vs ethanol ablation vs radiofrequency ablation?
Surgery = 94%
Ethanol = 72%
RFA = 90%
What’s the prognosis of primary hyperparathyroidism treated with surgery or ablation techniques?
- very good!
- metastasis = very rare
- hypocalcemia can be medically managed
- even if it’s a carcinoma, both tumour control and resolution of hyperparathyroidism = excellent
What’s the % of patients that will have recurrent hypercalcemia after definitive therapy?
10%
- and do a 2nd course of therapy
What’s the short-term outcome if hyperparathyroidism is not treated with surgery or ablative techniques?
Fine
- the disease is slowly progressive
- mild clinical signs
- low risk of kidney failure
How common is pancreatic beta-cell tumours in the dog and the cat?
rare in cats, uncommon in dogs
What’s the hallmark bloodwork changes for insulinoma?
low glucose level with normal to high insulin
What hormones are produced by insulinoma?
insulin!
but also:
- glucagon
- somatostatin
- pancreatic polypeptide
- growth hormone
- IGF-1
- gastrin
How aggressive pancreatic beta-cell tumour in people?
90% of insulinoma in people are benign
- 5-10% are associated with MEN-1
How aggressive is insulinoma in dogs?
Mostly malignant
- but malignancy does not consistently reflect behaviour
How common is metastasis in canine insulinoma?
50%
What are the most common metastatic sites of canine insulinoma?
- regional lymph nodes and liver = most common
- lungs = rare in dogs
What’s the WHO staging system for insulinoma?
Stage 1: T1N0M0
Stage 2: T1N1M0
Stage 3: T1N1M1
What difference in gene expression is noted between the low-metastatic and high-metastatic insulinoma
- Down regulation of acinar enzymes
- DNA and cell repair pathways
What are some histologically prognostic factors for canine insulinoma?
- Ki67
- tumour size
- TNM stage
- presence of necrosis
- cellular atypia
- stromal fibrosis
What’s neuroglycopenia?
the effect of hypoglycemia on the nervous system
What are some signs of hypoglycemia?
- faint/ collapse
- weakness/ ataxia
- disorientation
- change in behaviour
- seizure
What’s the pathophysiology of muscle tremors with hypoglycemia?
- catecholamine in released in response to hypoglycemia
- also have shaking, anxiety, and hunger
How is insulinoma diagnosed?
hypoglycemia (<60mg/dL/ 3.3mmol/L) with normal or high insulin.
- Insulin/glucose ratio is not accurate
- glycosylated hemoglobin is usually low with hypoglycemia, but it’s not pathognomonic for insulinoma
How good is u/s at diagnosing canine insulinoma?
- can only clearly identify and localize a mass in < 50% of cases
- also low sensitivity and specificity for detection of metastasis
Which imaging modality is more sensitive technique for identifying canine insulinoma: U/S, CT, or SPECT?
CT! (10/14)
- but also found a significant number of false positive metastases
- triple phase CT (esp late arterial phase) is pretty good
- SPECT sensitivity = 50%
How is canine insulinoma treated?
Definitive tx = surgery
- most tumours can be visualized or are palpable in surgery
Where is canine insulinoma most likely located?
can be found in equal frequency between the left and right limbs
What are some post-op complications of canine insulinoma removal?
- need to monitor the glucose level
- can have transient to long-term hyperglycemia
- pancreatitis
Which chemotherapy is used for treating canine insulinoma?
Streptozocin
- cytotoxic
- side effects include: hypoglycemia, diabetes mellitus, vomiting (during infusion), increased liver enzymes, mild hematological changes
- historically nephrotoxicity = DLT, but with aggressive saline diuresis, it’s ok
- can control tumour growth, but glycemic control may be no better than other medical treatments
What’s the MOA of prednisone for treating canine insulinoma?
- antagonizes insulin
- gluconeogenic
- glycogenolytic
What’s the MOA of diazoxide for treating canine insulinoma?
- not cytotoxic
- suppresses insulin release from beta cells
- stimulates hepatic gluconeogenesis and glycogenolysis
- inhibits cellular uptake of glucose
What are the side effects diazoxide?
uncommon
- ptyalism
- vomiting
- anorexia
- diarrhea
- expensive!!!
What’s the MOA of octreotide in treatment of canine insulinoma?
- somatostatin receptor ligand
- inhibits the synthesis and secretion of insulin by pancreatic beta cells
(also expensive)
What’s the outcome of canine insulinoma with partial pancreatectomy?
good!
MST: 12-14m; more recent ~2y (DFI of 1.3y)
- if followed with prednisone, MST = 1316d reported (~3.5y)
- also stage dependent
- Stage III MST < 6m
How is the glycemic control after partial pancreatectomy for dogs with insulinoma based on the different stages?
Stage 1: 50% will still still be normoglycemia at 14m
Stage II/III: < 20% are free of hypoglycemia at 14m
What’s the MST with medical therapy only for canine insulinoma?
MST = 452d (1.2y)
What’s the outcome of surgery for feline insulinoma?
MST 1-32m
What medical treatment options are available for cats with insulinoma?
- prednisolone
- diet
- octreotide
- no evidence to support the use of diazoxide or streptozocin
How common is gastrinoma in dogs and cats?
rare in dogs, very rare in cats
What’s Zollinger-Ellison syndrome?
Triad of non-beta cell neuroendocrine tumour of the pancreas, high gastrin, and GI ulcer
How metastatic is gastrinoma and what are the most common sites of metastasis?
- up to 85% of dogs and cats at diagnosis!
- liver, reginal LNs, spleen, peritoneum, small intestines, omentum or mesentery
What are the consequences of hypergastrinemia?
- gastric mucosal hyperplasia
- gastric acid hypersecretion
What are some common clinical signs of gastrinoma?
vomiting and weight loss = most common
- melena, abdominal pain, anorexia, regurgitation, hematemesis, hematochezia, and diarrhea can also occur
How does H2 and proton pump inhibitors influence gastrin level?
the effects of gastrin increase in mild and short-lived
- may not inhibit the diagnosis of a gastrinoma
What’s the treatment of choice of gastrinoma?
Exploratory laparotomy
- even with metastatic disease, tumour removal can enhance medical therapy
What’s the outcome of gastrinoma in dogs and cats?
MST 1 week to 26m!
What are some medical treatment options for gastrinoima in dogs?
octreotide - it was successful in 3 dogs
What’s a paraneoplastic syndrome of glucagonoma?
necrotizing migratory erythema
- hyperkeratosis, crusting, ulceration, and erosions
- footpads, mucocutaneous junctions, external genitalia, distal extremities, pressure points, and ventral abdomen
DDX: liver disease (more common for NME)
What’s the outcome of glucagonoma?
poor, highly metastatic
- NME may resolve with surgery or medical therapy
What bloodwork changes can be noted with glucagonoma?
hyperglycemia
- hypoaminoacidemia
- increased liver enzymes
Can glucagonoma be diagnosed on bloodwork?
plasma glucagon and amino acid level have been tried, but unknown sensitivity/ specificity
What’s the treatment for intestinal carcinoid?
Surgery, though metastasis is common on presentation
Where can intestinal carcinoids be located?
They are from the neuroendocrine cells of the GI system
- liver
- intestines
- gallbladder
- pancreas
What’s the prognosis of intestinal carcinoid?
poor, metastasis is common
Is SRT better than CFRT for canine pituitary tumours?
In one retrospective comparison study, the overall MST = 608d (1.6y)
- younger dogs (<9y) MST = 753d (~2y) vs 445d (1.2y)
- ST was not associated with protocol
What are some CT features of exocrine pancreatic carcinoma in dogs/ cats?
- well defined mass with contrast enhancement
- heterogenous
- more common in R lobe
- lymphadenopathy (esp with larger masses)
What’s the metastatic rate of canine thyroid carcinoma on presentaiton?
1/3
- 14-26% for LN mets
- 20-38% pulmonary mets
What does the thyroid follicular cells produce? medullary cells produce?
- Follicular cells = colloid, thyroid hormones and thyroglobulins
- Medullary cells = c-cells = parafollicular cells = calcitonin
What IHC markers can be used to distinguish between follicular thyroid, medullary thyroid, and parathyroid tumours?
- Follicular thyroid: thyroglobulin (+), thyroid-transcription factor 1 (+), neuroendocrine markers (-)
- Medullary thyroid: thyroglobulin (-), thyroid-transcription factor 1 (-), neuroendocrine markers (+), calcitonin (+), calcitonin gene-related peptide (+)
- Parathyroid: thyroglobulin (-), thyroid-transcription factor 1 (-), neuroendocrine markers (+), parathyroid hormone (+)
What’s the outcome of incompletely removed canine thyroid carcinoma without adjuvant therapy?
10m
What’s the relationship between gastrin and dogs with primary hyperparathyroidism?
27/151 (17.9%) of dogs with PHPT have hypergastrinemia, but this is independent of the presence of GI signs
What’s the prognosis of dogs with endocrine/ neuroendocrine tumours that develop bone metastasis?
With therapy, >100d
(compared to other tumour types, generally < 30d)
What’s the MST of canine thyroid neoplasia that underwent thyroidectomy?
MST = 802d (2.2y)
- risk factors for cancer related death: presence of metastasis, non-follicular carcinoma, administration of chemo
What’s the outcome of SRT for canine pheochromocytoma?
n = 8 (11Gy x 3 daily, or 7Gy x 5 EOD)
- all had resolution of clinical signs
- 5/8 still alive at median follow-up time of 25.8m (just over 2y)
- can resolve caval invasion
- RT AE mostly GI
What’s the outcome of Palladia for pheochromocytoma?
1 PR, 5 SD
Is there a insulin concentration difference in the stage and ST for canine insulinoma?
No…
there is no significant differences in insulin concentration between dogs with or without metastasis at diagnosis.
Is u/s guided core needle biopsy of thyroid tumours in dogs feasible?
yes.. apparently it’s safe
Which is more sensitive at diagnosing canine pheochromocytoma - plasma free noremetanephrine or metanephrine?
normeteanephrine! 100 % vs 73%
both have specificity of 94%
What’s the outcome of cats with insulinoma treated with surgery?
Study with 20 cats:
-18/20 had euglycemia or hyperglycemia after surgery
- MST = 863d (2.4y)
- Negative prognostic factors = young age, and low serum glucose level, metastasis, tumour invasion, and shorter time to euglycemia
( Veytsman et al, 2023)
How can pre-I131 USG in cats predict the risk of post-RAI azotemia in hyperthyroid cats?
if pre treatment USG > 1.035 –> 6.4% developed azotemia vs if pre-treatment USG < 1.035, then the risk is 44%
(Peterson and Rishniw, 2023)
What’s the post-op complication rate for unilateral adrenalectomy in dogs? What are some factors that contribute to poor outcome?
- Complication rate = 25%
- Peri-op mortality associated with: increased surgical time, medical treatment other than pheochromocytoma (that had no effect)
- Decreased overall ST: pancreatitis, aspiration pneumonia, ureternephrectomy
(Piegols et al 2023)
What’s the outcome of canine pituitary macrodenoma treated with RT?
- there was no significant difference between PDH and non-PDH macroadenoma for MST (590d vs 738d {1.6 vs 2y])
Rapastella, et al 2023
How good is PET-CT with 18-FDG for canine insulinoma staging?
Unpredictable tumoural avidity limits the value of (18) F-fluorodeoxyglucose positron emission tomography-CT for staging canine insulinomas.
What’s the outcome of cats with hypersomatotropism and DM treated with cabergoline?
in 23 cats
- IGF-1 concentration improved in 26%
- DM remission in 35%
(Miceli et al 2022)
Should alpha-blockers be used prior to surgery for dogs with pheochromocytoma?
53 dogs didn’t have pretreatment with pheochromocytoma and 44 survived to discharge with MST of 3.2y
What’s a risk factor of developing post-op hypocalcemia for primary parathyrodism?
- if pre-op hypercalcemia is > or = 1.75mEq/L = 7.5x risk of post-op hypocalcemia
(Burkhardt, et al 2021)
What U/S feature is more consistent with a malignant parathyroid tumour?
nodule > or = 8mm
(Burkhardt, et al 2021)
How accurate is U/S as pre-op assessment for primary parathyroids in terms of number of nodules affected and laterality compared to surgery?
- # of nodules: 65.9%
- laterality: 72.3%
What’s the outcome of feline hypersomatotropism treated with transsphenoidal hypophysectomy?
in 25 cats:
- MST = 1347d (3.7y)
- 23/24 can remission from hypersomatotropism
- 22/24 achieved diabetic remission
What are some common clinical signs for dogs with insulinoma?
weakness (60%), epileptic seizures (33.6%)
(Ryan et al 2021)
What’s the outcome of canine insulinoma treated with surgery?
MST = 20m, better than 8m for those treated medically.
- metastasis is the only variable associated with prognosis
What’s the detection of canine insulinoma with dual phase CT?
found nodules in 33/35 cases (94%)
- hyperattenuating in the arterial phase (21/22)
Can I-131 resolve hyperthyroidism due to ectopic thyroid tumours in dogs?
yes, 5/5
(Lyssens et al 2021)
What factors are associated with increased odds of relapse and decreased ST in dogs with insulinoma treated with surgery?
- post-op hypoglycemia
- stage
In this study, the MST was 372d (1y), Stage I = 652d (1.8y) and Stage II/III = 320d (8m)
(Del Busto et al 2020)
What’s the complication rate of FNA of adrenal tumour?
1% death
- 3/50 had acute hemorrhage
- 1/50 death due to respiratory distress
How does SDMA predict azotemia in hyperthyroid cats treated with I-131?
- An increased SDMA concentration above the reference interval prior to treatment has a high specificity but poor sensitivity for the prediction of post-treatment azotemia
- there is a discordance with post treatment creatinine and SDMA
What’s the outcome of SRT for dogs with thyroid carcinoma?
RR = 70%; 4 (20%) CR, 10 (50%) PR, 4 (20%) SD, and 2 (10%) PD
MPFS = 10m
MST = 1y
- metastasis was not a prognostic factor
(Lee et al 2020)
- responders MPFS = 1y vs 3m
- responder MST = 1.2y vs 3m
What’s the outcome of dogs with thyroid carcinoma treated with Palladia in naive/ rescue setting?
RR = 88.4%; 1 dog (3.8%) experienced a CR, 11 (42.3%) PR, 11 (42.3%) SD
- Naive MST = 563d (1.5y)
- Rescue MST = 1086d (~3y)
- dogs that were asymptomatic actually had shorter ST
(Sheppard-Olivares et al 2020)
Is the pretreatment T4 and post treatment T4 correlated in cats treated with a fixed dose of oral RAI?
nope!
(Yu et al 2020)
What’s the metastatic rate and pattern of canine thyroid carcinoma?
18.6% on presentation
- all medial retropharyngeal metastasis were ipsilateral (7/77, 9.1%): there was no contralateral mets
- 14/41 (34%) had metastatic deep cervical LN
- medullary or mixed follicular/medullary tumours (62.8%) were more likely to have metastasis than follicular (8.2%)
- All metastatic LNs are ipsilateral
(Skinner et al 2024)
What’s the outcome of adrenalectomy for ruptured adrenal mass?
- good if they survive the periop period
- short term (<2w) complications were 42% (21% death)
- MST = 574d (1.6y)
- MST = 900d (2.5y) if short term death is censored
What’s the significance of intra-op glucose level for dogs undergoing surgery for insulinoma?
- completeness of resection is related to the glucose level
- MDFI = 381d (~1y)
- MST = 762d (2y)
(Cogrolls et la 2022)
What’s the outcome of dogs with exocrine pancreatic adenocarcinoma treated with Palladia?
RR = 75%
MST ~ 90d (3m)
(Musser et al 2021)
What’s the outcome of endocrine status for cats with acromegaly treated with SRT?
- median time to max reduction is 399d (~13m)
- MST = 741d (~2y)
- single fraction 17Gy
(Watson-Skaggs et al 2021)
What’s the outcome of surgery for dogs with parathyroid tumours?
- MST = 2y
- 89/96 dogs have the hypercalcemia resolve within 7 days
- 34% develop hypocalcemia
(Erickson et al 2021)
Can size be used to distinguish between hyperplasia, adenoma, and adenocarcinoma of the parathyroid gland based on ultrasound?
- 3mm seems like a goo cut-off between hyperplasia and neoplasia
- but there is too much overlap
