Oncology: General, Treatments, Head, GIT and Abdominal masses (E2) Flashcards
What are the 6 hallmarks of a cancer cell?
Self-sufficiency in growth signals
Insensititvity to anti-growth signals
Tissue invasion and metastasis
Limitless replicative potential
Sustained angiogenesis
Evading apoptosis
What are a few causes of cancer?
Genes- DNA mutation
Diet- high fat, low fiber diets
Exposure to carcinogens and mutagens
Viruses
Age/alterations in immune system
What are the phases of multistep carcinogenesis? Which is rapid and which is slow? At what point do the changes stop being reversible?
Initiation- rapid, DNA damage but not enough to induce neoplastic trasformation
Promotion- reversible changes
Progression- slow and irreversible
What are 3 important aspects of obtaining a comprehensive history of a patient with a tumor?
- Doubling time (rapid vs slow growth)
- Extent of involvement (local vs systemic)
- Co-morbidities (continuum of disease)
How do you definitively establish a tissue diagnosis?
Cytopatholoy
From what 3 distinct cell types do most cancers come from?
Round cells
Mesenchymal cells
Epithelial cells
What are the types of round cell tumors?
Plasmacytoma
Histocytoma
MCT
Lymphoma
TVT
+/- Melanoma
(Please Help Me Learn This, Meow?)
Under a microscope, which tumor hass spindle-shaped, stellate or oval cells arranged in individually or in non-cohensive aggregates? What are some examples of these types of tumors?
Mesenchymal
Sarcomas: OSA, Chondrosarcoma, Fibrosarcoma, HSA
Which tumor has the best diagnostic yield (i.e. exfoliates the best), which has the lowest yield?
Best: Round cell
Poorest: Mesenchymal
How do carcinomas look microscopically? What type of cell tumor are these?
Round, cuboidal, columnar or olygonal cells arranged in cohesive sheets or clusters
Epithelial cell tumors
What does anisokaryosis mean?
Variation in nuclear size (characterstic of malignancy)
What does it mean that cytopatholgy has low sensitivity but high specificity?
Low sensitivity = false negatives likely
High specificity = false positives unlikely
With which neoplasm has needle tract implantation been reported?
Urogenital carcinomas
What are the 2 clinical techniques for FNA? Which is better?
Needle off- coring: better- less blood contamination and better needle control
Needle on-suction
What is the preferred technique for cytology slide preparation? When should you use the other technique?
Horizontal pull-apart
Use vertical pull-apart with fragile cells (e.g. LNs)
What question does staging answer? What system is it based on? What does staging require?
Is the tumor localized, spread regionally or diffusely?
WHO TNM (tumor, node, metastasis) system (0-IV)
Staging requires a series of generally non-invasive testing
What is required to grade a tissue? What does it establish/determine?
A block of tissue (e.g. biopsy, FNA)
It establishes inherent aggressiveness and allows definitive prognostication
Also inflences therapeutic recommendations
What do the stages T1-T4 indicate? What does the N stand for (in staging)? What does the M stand for?
The size and/or extent of the primary tumor
N= regional LNs
M= distant metastasis
T/F: If lymph nodes are normally sized (i.e. not enlaged), they are most likely not metastatic.
False, never assume!
How large does a nodule have to be in order for it to be visible on an x-ray?
7-9mm
What do you call tumor associated alternations in bodily structure or function occuring distant to the tumor?
Paraneoplastic syndromes
What tumors commonly cause the PNS hypercalcemia?
Anal sac ACA
LSA
Multiple myeloma
Mammary tumor
What type of tumor commonly causes the PNS hypoglycemia?
Intestinal leiomyosarcoma
What tumor causes neurologic PNS?
Thymoma
What is the cutaneous PNS that occurs with renal cyadenocarcinoma?
Nodular dermatofibrosis
What is the bone PNS caused by many primary lung tumors, esophageal tumors and metastatic tumors?
Hypertrophic osteopathy
T/F: Conventional chemoterapy drugs target all rapidly dividing cells.
True
What is adjuvant chemotherapy?
Chemo given as adjunct to local therapy (i.e. after sx)
Why is neoadjuvant chemo given?
To try to shrink the tumor prior to definitive treatment (i.e. sx)
What is it called when you are using chemo as the sole treatment for measurable disease?
Induction/maintenance chemotherapy
What is the purpose of palliative chemotherapy?
To improve QOL by helping alleviate signs (expectation is not to cure)
What do you call the dose of chemo that produces an acceptable level of toxicity?
MTD (maximum tolerated dose)
T/f: Chemotherapy dosages are based on toxicity rather than efficacy.
True
In what animals and with what drugs can using body surface area for chemo dosages be problematic?
Smaller patients, small breed dogs (receive higher dose)
Doxorubracin, Melphalan, Cis-and Carboplatin
What are the “4 R’s” that should be considered prior to any chemotherapy treatment?
Right drug
Right dose
Rigth route
Right patient
Which chemo drugs pose an increased risk for dogs with ABCB-1 gene mutations?
Vincristine
Vinblastine
Paclitaxel
Doxorubracin
What things are required for the safe handling of chemo drugs?
BCS (biological safety cabinet) - at least BSL-2
CSTDs (closed-system drug-transfer devices)
PPE- gloves, gowns, face shields + aseptic technique
Written policy and procedure for safe handling of chemo
What can you do to ensure client safety with chemotherapy drugs?
Provide handout and gloves
Make sure pills are never split or crushed
No handling of meds if nursing or pregnant
What are the 3 common adverse effects of cytotoxic chemotherpy?
BAG:
Bone marrow suppresion
Alopecia (non-shedding breeds only)
Gastrointestinal cells
Why must a CBC always be done on the day of chemo? (what are you looking for and what values are acceptable)
Neutrophils: Must be >/= 1500-2500 (/microL)
PTL: Must be >/= 50k-100k
What are you establishing with the CBC after the 1st chemo treatment?
The NADIR of the WBCs (expected low point of BM suppresion)
What does it mean when a chemo patient’s NADIR is <1000? What can be given to boost this number and is it commonly used, why or why not?
Myelosuppresion/neutropenia
Higher risk for systemic infection
Prophylactic antibiotics are warrented
Rx: Nupogen (Filgrastim)- uncommonly used because it is a human-source product and can cause HS reactions
What 2 chemo drugs commonly cause GI toxicity?
Cisplatin
Doxorubracin
What do you call chemo drugs that can kill cancer cells at any stage in the cell cycle?
Cell-cycle non-specific
Antimitotic chemo drugs disrupt or immbolize the mitotic spindle during mitosis. What are the 2 drug classes that fall into this category?
Vinca alkaloids (vincristine, vinblastine) **most commonly used**
Taxanes (paclitaxel, docetaxel)
What tumor types is vincristine used for and what are the 3 major side effects?
Vincristine: LSA and TVTs
Side effects: Gastrointestinal, vesicant, neuropathy
What class of chemo agent binds to DNA strands, inserts an alkyl group and changes the structure of the DNA, interfering with transcription, replication and repair machinery? Are these cell-cycle specific or non-specific?
Give some examples of drugs in this class. Which aspect of BAG do these drugs affect most?
Alkylating agents
Non-specific
Chlorambucil, CCNU,Cyclophosphamide, Melphalan- Bone marrow
What is a drug-specific toxicity of cyclophosphamide? What is this drug used for?
Affects bone marrow severely and causes sterile hemorrhagic cystitis
Used for LSA metronomic chemotherapy
(alkylating agent)
What is a drug-specific toxicity of CCNU? What can you give to lessen some of these effects? What tumors is this drug used for?
Strongly affects bone marrow and causes liver toxicity
Give with Denamarin
LSA, MCT, histocytic sarcoma
(alkylating agent)
What type of chemo agent is doxorubricin? What are some side effects and can you give anything to lessen these?
Cell-cycle non-specific Antibiotic agent
GI side effects
Dose-related cardiotoxicity- can give Dexrazoxane to reduce
Tinnitus
Vesicant (very strong)- can apply frozen peas (pee on it) or give Dexrazoxane within 3 hours
What chemo agent is known as “blue thunder”? What tumors is it used for and what type of agent is it?
Mitotoxantrone
TCC and LSA
Antibiotic agent
What is cisplatin and what are its side effects? Which drug is used as an alternative?
Platinum chemotherapy agent
Dogs- B,G, nephrotoxicity
NEVER USE IN CATS (SPLATS CATS)
Preferred alternative: Carboplatin (ok in cats and dogs for OSA and other sarcomas)
Why should elspar not be given IV?
It causes severe HS rxns which can lead to DIC
How does Tanovea work and what is it used for?
Inhibits DNA synthesis thus inhibitng lymphocyte and LSA cell line proliferation
LSA in dogs
(FDA approved)
How does metronomic chemotherapy help prevent recurrence? What are the pros and cons?
Eliminate break point by giving low dose continuous chemotherapy
Pro: Lower toxicity, reduced side effects, PO administration, lower cost
Cons: Not cytotoxic/ less potent, not designed to cure (palliative therapy)
What are the 3 MOAs for metronomic chemotherapy?
Anti-angiogenesis
Immunomodulation
Direct targeting
What cells does metronomic chemotherapy downregulate?
T-regulatory cells (CD4+, CD25+)
What substances form in the urine when sterile hemorrhagic cystitis occurs, resulting in urinating blood? What drug causes this? How can it be avoided?
Acrolein and 4-hydroxymetabolites
Cyclophosphamide
Giving furosemide concurrently helps prevent
How does Torceranib (Palladia) work?
Inhibits replication/growth of cells by blocking tyrisine kinase (irreversibly binding to receptor)
What type of treatment are tumor vaccines, oncolytic virus therapy, monoclonal antibodies and T-cell therapy?
Immunotherapy
For what type of tumors are there vaccines?
Oral melanoma (stage II or III) Oncept Canine Melanoma Vaccine
Feline fibrosarcoma Oncept Feline IL-2
What plant is used to reduce proliferation and increase apoptosis in cancer cells?
C. versicolor mushroom (Turkey Tail mushroom)
What chinese medication has been shown to improve clotting time and enhance platelet function? What tumor has it been shown effective against?
Yunnan Baiyao
HSA
What is the standard, accepted unit for radiation dose measurement?
Gray (Gy)
What tissues are considered early and late responding tissues (radiation therapy)?
Early: epithelial layers of skin or mucosa, bone marrow
Late: nervous tissue, bone
What does the term fractionation mean?
Dividing radiation therapy dose into multiple doses rather than one large dose to improve toleration and effectiveness of the treatment
What are the “Big 3” variables that dictate the reponse of tissue to radiation?
Total dose
Fraction size
Duration of treatment
What are the 3 forms of teletherapy? Which is superficial, which is deep?
Orthovoltage - superficial
Megavoltage - deep
Protons - superficial
What is stereotactic radiosurgery used to treat? How many doses are required?
OSA (distal limbs in dogs)
Single dose
What is RECIST?
Response Evaluation Criteria in Solid Tumors
Used to measure response to therapy, objective guidelines
Either get complete response (CR), partial response (PR- >30% reduction in tumor size), progressive disease (PD- >20% increase in tumor size) or stable disease (SD- <30% reduction and <20% increase in tumor size)
What is the purpose of phase 1 of clinical trials? Phase 2? Which phase is done after the drug has been approved?
1: Establishing the safety of the drug or device
2: Efficacy of the drug/device (small scale study)
Phase IV (4) is done post-approval (post-marketing surveillance)
What are the DDx for nasal planum tumors in cats? Dogs?
Cats: SCC, LSA, eosinophilic granuloma, MCT
Dogs: SCC, MCT, sarcoma (fibro-)
What is the therapy in which chemotherapeutic drugs are used in combination with high-voltage electric pulses resulting in reversible permiation of cell membranes, allowing more efficient entry of drugs into the cells?
Electrochemotherapy (ECT)
If an older cat develops an ear canal tumor, what is your top DDx? What is another Ddx?
Ceruminous gland adenocarcinoma
Undifferentiated SCC, Round cell tumors, Sarcomas
What surgery is indicated for ear canal tumors? What surgery should never be done?
TECA-BO
Never lateral canal resection
T/F: Assuming aggressive surgery and no pre-op mestastasis, ear canal tumors have a long MST in dogs and cats.
True
>58m in dogs
12-50mo in cats
What are negative prognostic indicators related to ear canal tumors?
Extension beyond ear canal
Diagnosis of SCC or undifferentiated sarcoma (adenocarcinoma is better)
Neuro signs
Vascular or lymphatic invasion (histology)
High mitotic index (histology)
What dogs tend to get sinonasal tumors? What is the classical presentation?
Older medium to large breed dolicocephalic dogs (esp those with high environmental contaminant exposure)
2-3mo hx of unilateral epistaxis, sneezing, open-mouth breathing, partial response to empirical treatments, facial deformity
What are the top DDx for sinonasal tumors in dogs? Cats?
Dogs: Carcinomas (ACA, SCC, undiff)
Cats: LSA
T/F: With sinonasal tumors, if there is not blood on the floor, you have not gotten a good biopsy.
True
What landmark should you use when performing a blind biopsy of a sinonasal tumor?
Medial canthus of eye
What is the MST for sinonasal tumors if we do nothing?
95 days
Why can COX-2 inhibitors be used for palliative treatment in dogs with nasal carcinomas?
80% of these tumros have COX-2 overespression which is used by the tumors to recrcuit blood vessels
COX-2 inhibtors (NSAIDs) are anti-angiogenic to the tumor
What is the go-to curative intent treatment for sinonasal tumors?
Radiation therapy - IMRT and SRT are best
What are negative prognostic factors for sinonasal tumors in dogs?
Older age
Epistaxis
Longer duration of CS
Advanced tumor stage (cribiform involvement)
Metastasis
SCC/undifferentiated carcinomas
Failue to achieve resolution of CS after tx
What is the go-to treatment for sinonasal tumors in cats?
Radiation + Chemo
T/F: Salivary tumors are most commonly adenocarcinomas or carcinomas. Surgery alone is rarely curative.
True
What cat breeds are at decreased disk for thyroid tumors?
Siamese
Himalayan
In dogs, ___% of thyroid tumors are malignant, and ___% are benign. The same rule is true for functionality, ___% are non-functional and ___% are functional. Most of these tumors are ____.
In cats, ___% of thyroid tumors are malignant and ___% are benign. The same rule is true for functionality. Most of these tumors are _____ .
In dogs, 90% of thyroid tumors are malignant, and 10% are benign. The same rule is true for functionality, 90% are non-functional and 10% are functional. Most of these tumors are CARCINOMAS.
In cats, 10% of thyroid tumors are malignant and 90% % are benign. The same rule is true for functionality. Most of these tumors are ADENOMAS .
Dogs with thyrpid tumors can have multiple distinct malignancies, which are often ________.
Intra-abdominal
What is the most important factor when you are staging a thyroid tumor?
Fixed vs Not fixed
What commonly occurs in dogs after bilateral thyroidectomy?
Hypocalcemia
T/F: Oral tumors are more common in dogs than cats, and more common in males than females.
True
What are the “Big 3” DDx for oral tumors in dogs? What are the “Big 2” for cats?
Dogs: Melanoma, SCC, Fibrosarcoma (in order of most to least common)
Cats: SCC, Fibrosarcoma
What type of biopsy is indicated for a proliferative oral tumor? Non-proliferative oral tumor?
Proliferative - Incisional “shave” biopsy (under heavy sedation)
Non-proliferative- Incisional biopsy never through lip and NOT under sedation
DO NOT DO EXCISIONAL BIOPSY
What is the most important prognostic/staging indicator for oral tumors?
Size
What special stain can be used to differentiate a sarcoma from an amelanotic melanoma?
Melan A
Thorough staging is required for oral tumors, especially malignant melanoma. What needs to be done do stage these?
Abdominal US
Full body CT
A 1.5 year old golden retreiver presents with a very large benign loooking oral tumor. The biospy comes back as a fibroma. Thoughts?
Probably not a fibroma, but a fibrosarcoma
Aggressive surgery required
T/F: Oral fibrosarcomas and SCC have low metastatic rates but are locally invasive.
True
Why are significant bone resorption and hypercalcemia common PNS in cats with oral SCC?
Tumors tend to express PTH-rp
What is the predilication site for oral SCC in cats?
Sublingual
What is the feline counterpart for acanthomatous amelioblastomas? What is done to control these tumors?
Feline Inductive Odotogenic tumors
Aggressive local surgery
Why do more rostral oral tumors havea better prognosis?
Easier to excise
What is the benign slow growing oral tumor common in dofs that contains proliferative fibroblastic connective and odontogenic tisssue and how should you address it?
Peripheral odotogenic fibroma
Surgically excise mass, preferrably using cryo. Can wait and see if you have a confirmative biopsy.
What can be done to shrink oral melanomas?
Radiation therapy
What drug should be given to all cats with oral SCC?
Piroxicam (prolongs survival)
What parasite causes esophageal tumors and what kind of tumor forms?
Spirocerca lupi
Sarcomas
What is the most common esophageal tumor? Where do they tend to form in cats and which sex is prediposed?
What is the other most likely DDx?
SCC
Middle 1/3 of esophagus just caudal to thoracic inlet, females prediposed (cats)
DDx: Leiomyosarcoma
What is the gold standard for diagnosing esophageal tumors?
Biopsy via esophagoscopy
What breeds are prediposed to gastric tumors? Sex prediliction?
Belgian Shepherds
Chow chows
Males >> Females
What is the most common clinical sign with gastric tumors?
Anorexia
What are the “Big 2” Ddx for gastric tumors in dogs? What is the most common gastric tumor in cats?
Dogs: ACA (adenocarcinoma), Leiomyosarcoma
Cats: LSA
Where do gastric adenocarcinomas tend to form? What do they look like?
Pyloric antrum/lesser curvature
Often scirrhous (firm, white or serosal surface), Linitis plastica (leather bottle)
What is the staging test of choice for gastric tumors? What is the best tool for assessing resectability?
Ultrasound (US-guided FNA/cytology)
Endoscopy
Which gastric tumor has a better prognosis, ACA or leiomyosarcoma?
Leiomyosarcoma (MST 12-21 mo)
(ASA most dead within 6mo)
Species: Large intestinal tumrs are more common than small intestinal tumors in ____ while the opposite is true in ____.
Dogs
Cats
What are the “Big 3” DDx for intestinal tumors in dogs? Cats?
Dogs: LSA, ACA, Leiomyosarcoma
Cats: LSA, ACA, MCT
Unlike other tumors, WHO staging for intestinal tumors depends on what rather than tumor size?
Depth of invasion
What are negative prognostic indicators for dogs with intestinal LSA? Cats?
Dogs: failure to achieve remission, diarrhea at initial presentation (MST 2 mo)
Cats: poor response to chemo (MST<3.5mo vs >11mo if do respond)
What is a negative prognostic indicator for dogs with ACA?
Being female (MST males 27days, females 28 days)
From what cells do gastrointestinal stromal tumors originate? What is their prediliction site?
Interstitial cells of Cajal
Cecum
____ is a receptacle for metastasis and receives mets 2.5x more frequently than developing primary tumors in dogs. In cats primary tumors of this organ are more common than mets.
Liver
What are the 4 general categories of primary liver tumors? What are these categories based on?
Hepatocellular
Bile duct
Neuroendocrine (carcinoid)
Mesenchymal
Based on cell of origin
What do you call a primary hepatobiliary tumor that is large, solitary and confined to a single liver tobe? What tumor type is most commonly of this morphology?
Massive
Hepatocellular
What is the morphologic descriptor for hepatocellular masses that are multifocal and involve all liver lobes? What tumor type is most commonly of this morphology?
Diffuse
Neuroendocrine
What staging modality is recommended for staging an assessing resectability for large or infiltrative hepatobiliary tumors?
CT
What is the most common liver tumor in dogs? Cats?
Dogs: HCC
Cats: Hepatocellular adenoma
What dictates the treatability of hepatocellular tumors?
Morphologic subtype
In division of the liver are complications of tumor removal most severe and why?
Right division
Vena cava runs through liver here
T/F: MST for dogs who have had surgery to remove a liver mass is significantly higher than for patients who did not undergo surgery.
True (>1460 days vs 270 days)
How much of the total mass of the liver can you remove and how long does it take for it to regain its original size?
75%
6 weeks
What tumor is common in cats and account for >50% of all feline hepatobiliary tumors?
Hepatobiliary cystadenoma
What is a risk factor for bile duct carcinomas in dogs and cats?
Trematode infestation
What is carcinomatosis and in what species does it occur?
Diffuse intraperitoneal mets from bile duct carcinomas
Cats
T/F: Chemotherapy and RT are not effective for bile duct carcinomas.
True
How are neuroendocrine tumors differentiated from carcinomas? Does this tumor occur in younger or older animals? Is it common?
Silver stains
Younger
No, rare
What is the non-invasive interventional radiologic technique used to isolate affected liver lobes microvascularly (i.e. stop blood supply)?
Chemoembolization
Why does chemotherapy not work well for liver tumors? How do you bypass the issues that make chemo ineffective?
Rapid development of drug resistance
Bypass by using chemoembolization
Why does radiation therapy not work well for liver tumors?
Liver cannot tolerate the high levels of radiation (>30 Gy) required to achieve remissions
Where is the preferential site of metastasis for renal tumors?
Lungs
What are the 4 general categories of primary renal tumors?
Renal tubular carcinomas
Transitional cell carcinomas
Nephrobastic tumors
Non-epithelial tumors (Sarcomas and LSA)
What PSA occurs in GSD with renal cystadenocarcinoma?
Nodular dermatofibrosis
Females get uterine leiomyomas
What is the gold standard for assessing and staging renal tumors?
Abdominal ultrasound + US guided FNA/cytology
Why do we tend to shy away from using excretory urography for renal tumors?
Contrast agents are nephrotoxic and could compromise the healthy kidney
Why would you want to use CT to work-up/stage a renal tumor?
To ensure the caudal vena cava is not being infltrated
What is the most common renal tumor in dogs? Is it usually uni- or bilateral? What is the most common PNS associated with this tumor?
Renal cell carcinoma
Unilateral
Polycythemia
Aside from the autosomal dominant cystadenocarcinomas that GSD get, what congenital tumor also affects young dogs? What is this tumor called in humans?
Nephroblastomas
Humans: Wilms’ tumor
What is the most common renal tumor in cats? Why is staging very important? Is it usually uni- or bilateral?
Lymphoma
Staging important because LSA is often multicentric
ALWAYS consider disease bilateral
How is renal lymphoma treated in cats
Multi-agent chemotherapy
(NEVER SURGERY)
What is the treatment for renal carcinoma in dogs?
Surgery (resistant to chemo, hormonal therapy and RT)
What symptoms accopany functional adrenocortical tumors originating in the zona glomerulosa?
Cushinoid symptoms
Where do pheochromocytomas originate? What do they produce?
Medulla of adrenal gland
Epi, norepi, dopamine
If a dog is asymptomatic and has an adrenal mass that is ____cm it is probably benign. Serial US should be done every ________ to monitor the mass and track its growth.
<2cm
3 months
What tests can you use to confirm functionality of an adrenocortical ACA or adenoma?
ACTH stim
U:C ratio
What test can you perform to confirm that an adrenocortical tumor is adrenal dependent?
Endogenous ACTH
What test can you use to diagnose a pheochromocytoma?
Metanephrine/Normetaneohrine to Creatinine ratio (urine test)
If you suspect that a tumor is a pheochromocytoma, what should you pre-treat the animal with before surgery? Why?
Phenoxybenzamine (q2-3 weeks)
To minimize the potential for surges in blood pressure during surgery
T/F: The prognosis is the same regardness of whether an adrenal tumor is an ACA or an adenoma.
True
