Oncology Flashcards
What is the reported overall survival time for tonsillar carcinomas in dogs, all treatment modalities combined (surgery, chemotherapy (conventional, tyrosine kinase inhibitors or metronomic chemotherapy), radiotherapy, nonsteroidal anti- inflammatory drugs (NSAIDs) or a combination of these) ?
Overall survival time was 126 days (95% confidence interval [CI], 88-164). Significantly longer survival was seen in dogs without evidence of metastatic disease (median survival time, 381 days; 95% CI, 116-646).
Ref : JVIM dec 2023, Treggiari, Tonsillar carcinoma in dogs: Treatment outcome and potential prognostic factors in 123 cases
Between primary tonsillar carcinoma and non-tonsillar oral carcinomas in dogs, which one has the higher potential for local metastatic disease ?
Primary tonsillar carcinoma is reported rarely in dogs when compared to non-tonsillar oral carcinomas and has a higher potential for local metastatic disease (up to 73%), when compared to oral carcinomas in other locations. Metastatic disease usually involves regional lymph nodes (mandibular, retropharyngeal, cervical) and lungs.
Ref : Mas A, Blackwood L, Cripps P, et al. Canine tonsillar squamous cell carcinoma—a multi-centre retrospective review of 44 clinical cases. J Small Anim Pract. 2011;52:359-364.
JVIM dec 2023, Treggiari, Tonsillar carcinoma in dogs: Treatment outcome and potential prognostic factors in 123 cases
Which factors are positive prognostic factors for dogs with primary tonsillar carcinoma ?
Absence of metastatic disease, absence of clinicals signs at presentation, surgery (tonsillectomy), use of adjuvant chemotherapy and use of NSAIDs.
Ref : JVIM dec 2023, Treggiari, Tonsillar carcinoma in dogs: Treatment outcome and potential prognostic factors in 123 cases
What is the use of telomerase in cancer (and germinal) cells?
It allows replication of telomeres and increase lifespan of cells
What is the purpose of mesna administration with cyclophosphamide?
Reduce risks of cystitis (binding in the urine)
What is the purpose of the administration of dexrazoxane with Doxorubicin?
Reduce cardiotoxicity and lesions after extravasation
What is the difference between overal response rate and clinical benefit?
Clinical benefit also includes stable disease
True or false: cross resistance in chemotherapy does not occur with alkylating agents?
True
True or false: definitive intent RT protocols usually consist of large number or low dose fractions with more acute side effects and less late side effects
True
True or false: palliative intent RT protocols usually consist of small number of high dose fractions with less acute side effects and more late side effects
True
How does radiation interact with tissue?
A photon removes an orbiting electron from an atome (ionization) and a second photon is emitted from this action. The electron and secondary photon can interact with the tissue. The electrons emitted damage the tissues.
True or false: low energy X-ray (such as brachytherapy) deposit the energy at or just below the skin surface
True (and high energy deposit most at greater depth - “skin sparing”)
What are the 4R that determine response to RT?
Repair (intensity of damage)
Redistribution (G1 and mid-S phase cells are more resistant, cells are redistributed into synchron phases)
Repopulation (cellular division)
Reoxygenation (O2 increases RT damages)
Of what is predominantly dependent acute toxicity after RT?
The total dose of radiation (higher dose, higher risk) but also shorter time of administration and higher fraction size
What type of tissue is mainly affected by acute toxicity of RT? And late toxicity?
Acute: rapidly renewing tissue
Late: slowly proliferating tissue
On what depends the likelihood of late toxicity or RT?
The fraction size (the higher, the higher the risk)
Do dogs who have Mast cell tumor with KIT mutation respond better to TKI treatment ?
Yes
Almost all myelosuppressive chemotherapeutics have a nadir at 6-8 days, except 2 molecules, which ones?
Lomustine in cats: 7-28 days
Carboplatine: 14 days in dogs, 25 days in cats
True or false: coadministration of l-asparaginase and vincristine may result in more severe neutropenia
True
To which chemotherapeutics MDR-1 dogs are more susceptible?
Vincristine, vinblastine, Doxorubicin…
Which chemotherapeutics more frequently produce thrombocytopenia?
Carboplatine, lomustine, Doxorubicin, melphalan…
What chemotherapeutics extravasation cause the more damage?
Vincristine, vinblastine, doxorubicine…
True or false: Vincristine via a neurotoxic effect may induce iléus in dogs and cats
True
What is the impact of liposomal form of Doxorubicin?
Reduced cardiotoxicity but new dermatologic toxicity
True or false: vincristine is mainly eliminated via biliary excretion and should be avoided or dose reduced in case of marked cholestasis
True
True or false: Vincristine risks to be more neurotoxic in case of MDR-1 dogs
True
What is acrolein?
An inactive metabolite of cyclophosphamide that is a direct urothelial irritant
What can reduce cystitis secondary to cyclophosphamide ?
Mesna or furosemide administration
What type of hypersensitivity reaction may be seen with l-asparaginase? And Doxorubicin?
L-asparaginase : type I (IgE)
Doxorubicin: histamine release from mast cells with rapid administration (non IgE)
Why is cisplatin contraindicated in cats?
Fatal pulmonary edema
What may result from high cumulative doses of lomustine in cats?
Pulmonary hypertension and fibrosis
True or false: CSF cytology is more useful for the diagnosis of CNS lymphoma in dogs than in cats
True due to the extradural form preponderance in cats
In cats suspected of CNS lymphoma what other 2 sites are frequently involved?
Kidneys and bone marrow
What chemotherapeutics may act on a CNS lymphoma?
L-asparaginase, cytosine arabinoside and corticosteroids
Name prognostic factors of lymphoma in dogs
Immunophenotype, clinical substage, histopathology, anemia, corticosteroid treatment, cranial mediastinal lymphadenopathy
True or false: approximately 10% of acute lymphoblastic leukemia are aleukemic leukemia (absence of peripheral circulation)
True
Of leukemia and lymphoma, which one should be CD34+
Leukemia
Name myeloma related disorders (4)
Multiple myeloma
Extramedullary plasmacytoma
IgM macroglobulinemia (Waldenstrom)
Ig secreting lymphoma/leukemia
True or false: in myeloma related disorders, hyper viscosity syndrome is more frequent with IgM macroglobulinemia
True, due to its high molecular weight
What is the diagnosis of multiple myeloma?
Bone marrow plasmacytosis, M-component in the urine or blood and bone/visceral lesion (if the last is absent, progressive increase in M-component should be assessed)
What is the predominant M-component in multiple myeloma in dogs? And in cats?
Dogs: IgA (and IgG)
Cats: IgG
What are two main forms of papilloma associated with age in dogs?
Cutaneous form in older dogs
Oral papillomatosis in young or immunocompromised dogs
In what tumor may rarely progress papilloma in dogs?
Carcinoma
To what might be viral papillomas precursors in cats?
Squamous cell carcinoma
To what tumor, sun damage may be a predisposition in dogs and cats?
Cutaneous squamous cell carcinoma
What is Bowen disease in cats?
Multicentric in situ SCC, might be due to papillomavirus
What is generally the behaviour of melanoma from a mucocutaneous junction? And haired skin?
Mucocutaneous: malignant (including digital)
Haired skin: benign
True or false: It is difficult to predict the biological behaviour of melanoma in cats based on the mitotic index
True
What is the target of the vaccine against melanoma in dogs?
Tyrosinase, an enzyme necessary for the synthesis of melanin
What are the IHC markers of GIST?
GIST: KIT +, DOG1 +, vimentin +
Leiomyoma/leiomyosarcoma: SMA +
True or false: chronic UV light exposure has been associated with dermal hemangiosarcoma along the ventral abdomen or conjunctive
True
Does sterilisation have an impact on hemangiosarcoma in dogs?
Yes, female neutered seem overrepresented
What biomarker may be useful for hemangiosarcoma?
Collagène XXVII
What are the two most common sites of osteosarcoma in dogs?
Proximal humerus and distal radius
What are the two main localisation of feline osteosarcoma?
Proximal humerus and digits
Brachycephalic breeds are predisposed to high grade or low grade mastocytomas ?
Low grade
What coloration and what marker may be useful to see mast cells?
Toluidine blue and CD117
What diseases are associated with Langerhans cells?
Histiocytoma,
Cutaneous Langerhans cell histiocytosis (dog)
Pulmonary Langerhans cell histiocytosis (cats
What influences the differentiation of monocytes into macrophages ? And dendritic cells?
M-CSF –> Macrophages
GM-CSF –> dendritic cells etc ..
What are the cell markers of Langerhans cells?
E-cadherin, CD1a, CD11c/CD18
What are the diseases associated with dendritic cells?
Cutaneous and systemic histiocytosis, histiocytic sarcoma and feline progressive histiocytosis
What are the cell markers of dendritic cells?
CD1a, CD11c/CD18 and for reactive histiocytosis CD4 and CD90
What are the cells of hemophagocytic histiocytic sarcoma and what are the markers?
Macrophages : faible CD1a et CD11d/CD18
True or false: malignant mammary tumors are rare in dogs of <5 years old
True
True or false: obesity and high fat diets have been linked to increased risk of mammary tumor in dogs
True (higher grade and diagnosed at younger age)
What are inflammatory mammary carcinomas?
Rapidly growing tumors with signs of pain, inflammation +/- edema of extremities with a bad prognosis (surgery is not indicated in this case)
What are the three “stop” codon?
TAG, TGA, TAA
Which class of chemotherapeutics may have cross-resistances ?
Antitumor antibiotics (ex: Doxorubicin) and mitotic inhibitors (ex: vinca alkaloids)
Which class of chemotherapeutics are substrate for the MDR pump (p-gp)?
Antitumor antibiotics (ex: Doxorubicin) and mitotic inhibitors (ex: vinca alkaloids)
Which chemotherapeutics are the most myelosuppressives ?
Doxorubicine, mitoxantrone, vinblastine, vinorelbine, lomustine, cyclophosphamide, carboplatine
In which cell cycle phases are cells most sensitive to radiation therapy?
G2 and M
What is the main side effect of rabacfosadine in dogs ?
Dermatologic toxicosis (pruritus, erythema and alopecia)
Which vitamin can lower the risks of palmar-plantar erythrodysesthesia in dogs administered IV liposomal Doxorubicin ?
Pyridoxine (vitamin B6)
Which chemotherapeutic may induce fatal neurotoxicosis in cats ?
5-FU
What are the risk factors for canine dermal SCC?
Thin, non pigmented skin and exposure to sun
Which vaccines are associated with feline injection site fibrosarcoma?
Rabies and FeLV vaccines
What 3 markers are used for IHC to differentiate between GIST and leiomyosarcoma?
GIST: (c-kit)CD117+, DOG1+, SMA+/-
Leiomyosarcoma: CD117-, DOG1-, SMA+
What is the main drawback of stereotactic radiotherapy in dogs with osteosarcoma?
The high risk of pathological fracture
What has been associated with periarticular histiocytic sarcome ?
Previous joint disease/cranial cruciate ligament rupture
Between dogs and cats, which one most frequently has solitary mammary gland tumor ?
Cats
What mast cell tumor localisation has the worst outcome?
Scrotal/preputial
