Exam 1 - Paraneoplastic Syndromes & Cancer Flashcards
what is paraneoplastic syndrome?
alteration in body structure and/or function that occur distant to the tumor
what may be the first sign of malignancy in cancer?
presence of paraneoplastic syndrome
paraneoplastic syndromes _______ underlying malignancy
parallels
what is paraneoplastic syndrome associated with?
noninvasive actions of the tumor
T/F: paraneoplastic syndrome can result in greater morbidity than the tumor itself
true
causes of paraneoplastic syndrome is variable, but is most commonly associated with what?
production of small molecules (ie, cytokines, hormones) that are released into circulation
T/F: paraneoplastic syndrome may be the first sign of malignancy & may be indicative of certain histology
true
how do you treat paraneoplastic syndrome?
you must address the primary tumor
what happens if you can’t treat the primary tumor in an animal with paraneoplastic syndrome?
supportive care may alleviate some of the clinical signs but complete control of the syndrome is highly unlikely & any improvement is usually short lived
what is cancer cachexia?
weight loss & metabolic abnormalities in cancer patients despite adequate nutritional intake
what is cancer anorexia?
alterations & abnormalities due to poor nutritional intake
when considering GI manifestations of cancer, what is likely to kill the animal before the primary tumor?
cancer cachexia/anorexia
how do you treat cancer cachexia?
treat the underlying disease, increase intake!!! calculate RER**, small frequent meals, calorie dense diet, & monitor the animal closely
how do you treat cancer anorexia?
treat underlying disease, nausea vs. inappetence (anti-emetics, gastroprotectants, & appetite stimulants), highly palatable (bland) diet, & feeding tube placement (sooner rather than later)
T/F: initially getting a cancer patient to eat something is better than them not eating anything
true - keep it bland & once eating again, try to transition to a more balanced diet
why should you consider feeding tube placement in cancer patients?
-why is the patient anorexia
-feeding tube likely to be short or long term
-is the patient likely to start eating again once the tumor is treated
-patient temperament
-medication administration
what is PLE as a GI manifestation of cancer?
serum proteins are lost into the gi tract leading to hypoproteinemia through either impaired synthesis or increased loss into the gi tract or urine
why is it important to remember that the half-life of serum proteins is long?
because it is long, the hypoproteinemia represents a long term protein loss
in PLE, the increase in mucosal serum protein permeability leads to what in the gi tract?
erosion, ulceration, & lymphatic obstruction
gastroduodenal ulceration is most commonly seen with what tumor? why?
canine mast cell tumors
excess production of histamine & stimulation of gastric acid production
what is a gastrinoma?
gastrin-secreting non-islet pancreatic tumor
what clinical signs are associated with gastrinomas?
lethargy, blood loss, vomiting, anorexia, & abdominal pain
how would you treat gastroduodenal ulceration as a result of a mast cell tumor?
treat underlying disease - MCT causing ulceration are often metastatic, large, & +/- visceral involvement
complete control may not be possible - palliative care
in a dog with a known mast cell tumor, presenting with vomiting, blood loos, & abdominal pain, why would you pick these medications?
animal likely has gastroduodenal ulceration as a result of the MCT - essentially palliative care to make the animal more comfortable
what is the most common cause of hypercalcemia in the dog?
cancer
hypercalcemia of malignancy is ___ of canine hypercalcemia cases & ___ of feline hypercalcemia cases
2/3 of canine
1/3 of feline
what is the most common lab abnormality seen with lymphoma?
hypercalcemia
what are some examples of other tumors that may cause hypercalcemia?
anal sac apocrine gland adenocarcinoma, thymoma, thyroid carcinoma
what is the most common mechanism of hypercalcemia seen in lymphoma & AGASACA?
ectopic production of parathyroid hormone or parathyroid related peptide (PTHrp)
extensive multifocal lytic bone metastasis is seen in what kind of cancer & causes what lab abnormality?
multiple myeloma & hypercalcemia
what are 4 examples of other causes of hypercalcemia?
-primary hyperparathyroidism
-tumor associated prostaglandins
-interleukin 1b
-transforming growth factor beta (TGF-b)
how is hypercalcemia diagnosed?
total serum calcium, ionized calcium, & hypercalcemia panel (michigan state)
T/F: when running diagnostics for hypercalcemia, you don’t have to account for serum albumin
true
what would you expect your results to be for a hypercalcemic patient in regards to, PTH, PTH-rp, serum Ca, & serum P?
PTH - LOW
PTH-rp - HIGH
serum ca - HIGH
serum P - LOW
why is hypercalcemia considered a medical emergency?
renal damage can occur & azotemia may or may not be reversible
what is the mechanism of PU/PD in a hypercalcemic patient?
initially occurs due to impaired action of ADH on the tubular cells of the collecting ducts - dehydration is common
what renal damage can occur in hypercalcemic patients?
renal vasoconstriction
mineralization of the renal tubules, basement membrane, or interstitium
tubular degeneration or necrosis
interstitial fibrosis
what should your treatment plan focus on in a patient with hypercalcemia?
treat the hypercalcemia while trying to make the diagnosis!!!! focus on supporting the kidneys
in a patient with hypercalcemia, what should your treatment plan avoid?
treatments that would negatively impact your ability to make a diagnosis (corticosteroids) & anything that would hurt the kidneys (no lasix- would further dehydrate)
your symptomatic treatment for hypercalcemia should address what?
promote the loss of calcium
increase renal excretion
inhibit bone reabsorption
where do you start with a hypercalcemic patient?
aggressive iv fluid diuresis (saline), no furosemide, supportive meds (anti-emetics, appetite stimulants, gastric protectants)
if your patient has lymphoma & is hypercalcemic, what does your treatment plan start with?
injection of dex sp, switch to oral pred once eating, & start chemo
if your patient has AGASACA & is hypercalcemic, where do you start in your treatment plan? what is your goal?
avoid a steroid!!
if more than IV fluids are required, administer bisphosphonates
make patient a surgical candidate
what is the most common cancer that causes hypoglycemia?
insulinoma
what is a pathognomonic finding in a suspect case of insulinoma?
hypoglycemia associated with high insulin levels
with hypoglycemia as an endocrinologic manifestation of cancer, what are common characteristics of the primary tumor?
usually very large, increased use by the tumor, decreased hepatic glycogenolysis/gluconeogenesis, & secretion of insulin, IGF-1, or IGF-2
how do you treat hypoglycemia as a manifestation of cancer?
emergency!!! can cause hypoglycemic seizures!!
iv catheter & dextrose bolus (0.5ml/kg of 50% dextrose diluted 1:1 with an isotonic crystalloid)
dextrose CRI only if needed (2.5-5%)
treat the patient, not the numbers
what is the primary choice when treating an insulinoma?
surgical removal - get the nodule out
how does prednisone work when used for insulinoma treatment?
insulin antagonizing, gluconeogenic, & glycogenolytic
how does diazoxide work in treating insulinomas?
suppresses insulin release from beta cells, stimulates hepatic gluconeogenesis & glycogenolysis, & inhibits cellular uptake of glucose
how does octreotide work in treating insulinomas?
somatostatin receptor ligand, & inhibits synthesis & secretion of insulin
how does streptozocin work in treating insulinomas?
chemo that destroys pancreatic beta cells
how does palladia work in treating insulinomas?
tyrosine kinase inhibitor
hypergammaglobulinemia is an example of what kind of manifestation of cancer?
hematological
what are monoclonal gammopathies?
excessive production of proteins from a monoclonal line of immunoglobulin producing plasma cells or lymphocytes
what kinds of cancer can have monoclonal gammopathies?
plasma cell tumors mostly
sometimes lymphoma/leukemia - b cell if so
if an animal with hyperviscosity of their blood due to a monoclonal gammopathy is in your clinic, what clinical signs would you expect to see?
ataxia, dementia, depression, heart disease, heart failure, seizures, & coma
cats with hyperviscosity due to a monoclonal gammopathy commonly have heart failure why?
heart is working so hard to pump the thick blood
if an animal with tissue hypoxia & bleeding due to a monoclonal gammopathy is in your clinic, what clinical signs would you expect to see?
poor platelet aggregation, platelets coated in immunoglobulins, & release of platelet factor III
if an animal with ocular disorders due to a monoclonal gammopathy is in your clinic, what clinical signs would you expect to see?
retinal hemorrhage or detachment (increased ocular pressure)
what diagnostic test would you run if you suspect hypergammaglobulinemia?
protein electrophoresis
what does this result represent?
monoclonal protein electrophoresis
what does this result represent?
polyclonal protein electrophoresis - chronic inflammatory granular issues!!!
why may you see anemia as a hematological manifestation of cancer?
disordered iron storage & metabolism, shortened life span of RBC,& decreased bone marrow response
if a cancer patient presents with IMHA, what should you do?
when possible, treat the primary tumor
surgical removal
start immunosuppressive therapy
______ ____ anemia & __________ may also be hematological manifestations of cancer
blood loss
myelophthisis
what tumor types can cause erythrocytosis?
renal tumors, lymphoma, lung tumors, liver tumors, cecal leiomyosarcoma, nasal fibrosarcoma, & TVT
what are 3 causes of erythrocytosis?
overproduction of erythropoietin
erythropoietin from renal hypoxia
increased production of HIF-1
T/F: it is important to differentiate primary from secondary erythrocytosis
true
what tumor types commonly cause neutrophilic leukocytosis? typical cell lines involved?
lymphoma, renal tumors, primary lung tumors, rectal polyps, & metastatic fibrosarcoma
G-CSF or GM-CSF
in a cancer patient with neutrophilic leukocytosis, do their neutrophils work?
function varies - unlikely because it’s disordered
what hematological manifestation of cancer is reported to occur in up to 36% of cancer patients prior to starting chemo?
thrombocytopenia
what are the causes of thrombocytopenia?
platelet destruction, platelet sequestration, consumption, decreased production, & ITP
what is the most common cause of hypocoagulability in cancer patients?
thrombocytopenia & platelet dysfunction
what is the most common mechanism of hypocoagulability in cancer patients?
release of heparin by MCT which inactivate clotting factors XI, X, & IX
which is more common in cancer patients, hypocoagulability or hypercoagulability?
hypercoagulability
what is the incidence of DIC in dogs with malignant neoplasia? what were the tumor types involved?
~10%
hemangiosarcoma, inflammatory mammary carcinoma, thyroid carcinoma, intra-abdominal tumors, & primary lung tumors
what is shinny skin syndrome in cats a result of?
progressive, non-scarring, acute, bilateral, symmetrical (ventrum & limbs), & glistening skin & hair easily epilates (severe follicular atrophy)
what type of cancer is has shinny skin syndrome as a result?
pancreatic carcinoma in cats
what are the clinical signs of thymoma in cats?
nonpruritic scaling & mild erythema on the head & pinnae, & progressively involves the neck, trunk, & limbs
pancreatic carcinoma in cats results in what kind of clinical manifestation?
cutaneous - alopecia
how is thymoma treated?
most cats don’t undergo treatment - typically sx removal of the thymoma results in the resolution of skin lesions
thymoma in cats has a cutaneous manifestation of what?
exfoliative dermatitis
what is nodular dermatofibrosis?
slowly growing cutaneous nodules associated with bilateral renal cystadenocarcinoma - well differentiated in collagen tissue
where is nodular dermatofibrosis most commonly found? what breed is predisposed?
limbs
german shepherds - autosomal dominance, mutation in birt-hogg-dude locus
superficial necrolytic dermatitis is commonly associated with what tumor type?
glucagonoma
what is a glucagonoma?
glucagon secreting tumors of pancreas or liver - hepatic disease (hepatocutaneous syndrome) & diabetes mellitus
what is superficial necrolytic dermatitis?
erosive blistering & ulceration
what major clinical sign is seen on the foot pads of animals affected with superficial necrolytic dermatitis?
fissuring, ulceration, & crusting of the foot pads
what clinical signs are seen with animals that have superficial necrolytic dermatitis?
erosions & ulcerations with alopecia, exudation & adherent crusts (feet, pressure points, flank, perineal area, muzzle, mucocutaneous junctions, & oral cavity)
myasthenia gravis is most commonly seen in dogs with what tumor type?
thymoma!!
does myasthenia gravis associated with thymoma carry a better or worse prognosis? why?
worse - animals typically get megaesophagus +/- aspiration pneumonia
hypertrophic osteopathy is most commonly seen with what kind of tumors?
primary lung tumors - metastatic osteosarcoma
what is hypertrophic osteodystrophy?
periosteal proliferation along the shafts of the long bones in response to malignant or non-malignant disease
what are the clinical signs of hypertrophic osteodystrophy?
shifting lameness, difficulty ambulating, ocular discharge & episcleral injection, pyrexia, lethargy, decreased appetite, heat, pain, & swelling on palpation of limbs
what is the treatment for hypertrophic osteodystrophy?
removal of primary tumor if possible, NSAIDS, steroids, bisphosphonates, & euthanasia
what is this condition known as?
hypertrophic osteodystrophy
what is this? what tumor is it associated with?
superficial necrolytic dermatitis
glucagonomas
this is associated with bilateral renal cystadenocarcinomas, what is it?
nodular dermatofibrosis
what is this?
renal cystadenocarcinoma
what tumor is this condition associated with?
pancreatic carcinomas in cats
this skin lesion is commonly seen with thymomas in cats - what is it?
exfoliative dermatitis
