Oncology

Question 1

Define:

• Transcription

- Translation

Answer 1

Transcription = the formation of RNA from DNA
Translation = the formation of proteins from RNA

Question 2

Molecular components of a DNA nucleotide?

Answer 2

(backbone) Deoxyribose + phosphoric acid bound to a base (pyrimidine/purine).

The base binds to the deoxyribose unit.

Question 3

Which base is substituted for uracil in RNA?

Answer 3

Thymine

Question 4

Which enzyme is responsible for transcription?

Answer 4

RNA polymerase

Question 5

Define complete response (CR)

Answer 5

A complete resolution of the tumour and clinical signs f disease

Question 6

Define partial response (PR)

Answer 6

Decrease in tumour volume >50% or diameter >30%

Question 7

Define stable disease (SD)

Answer 7

Neither increase or decrease in tumour size or disease symptoms (+/- 20% diameter change)

Question 8

Define progression free interval (PFI) vs. disease free interval (DFI)

Answer 8

PFI = the time in which there is no progressive growth of the tumour

DFI = the time in which the patient is free from disease recurrence.

Question 9

What type of agent is lomustine?

Answer 9

Alkylating agent

Question 10

What type of agent is cyclophosphamide?

Answer 10

Alkylating agent

Question 11

What type of agent is chlorambucil?

Answer 11

alkylating agent

Question 12

What type of agent is doxorubicin?

Answer 12

Anti-tumour antibiotic

Question 13

What type of agent is vincristine?

Answer 13

Anti-microtubule agent

Question 14

What type of agent is carboplatin?

Answer 14

Platinum compound that cross links DNA

Question 15

Pre-treatment considerations for taxanes (e.g. paclitaxel0

Answer 15

These agents can cause marked hypersensitivity reactions so require pretreatment with anti-histamines and corticosteroids as well as a prolonged infusion. For this reason they are rarely used in veterinary medicine.

Question 16

Unique side effect of vincristine in cats?

Answer 16

Paralytic ileus (it can cause peripheral neurotoxicity)

Question 17

Vesicant chemotherapy drugs and treatments

Answer 17

Vincristine = HEAT and hyaluronidase, DMSO, flucinolone, flunixin
Doxorubicin = COLD and dexraxozane +/- DMSO

Meclorathamine = sodium thiosulfate
Actinomycin D = COLD

Question 18

Dose limiting toxicity of chlorambucil?

Answer 18

Myelosupression - this occurs after 2-3 weeks of therapy.

Question 19

Unusual neurological side effect of chlorambucil

Answer 19

Cerebellar toxicity

Question 20

What is the mechanism of action of cyclophosphamides bladder toxicity?

Answer 20

Acrolein is a metabolite of cyclophosphamide that is toxic to the bladder mucosa.

Question 21

Why should dacarbazine be avoided in cats?

Answer 21

It is not thought to be converted to enough of its active metabolite.

Question 22

Unique side effects of lomustine in cats and dogs?

Answer 22

Dogs: hepatotoxicity with chronic use
Cats: pulmonary fibrosis

Question 23

Specific GI side effect of doxorubicin

Answer 23

Colitis (often haemorrhage)

Question 24

Side effect of doxorubicin in cats?

Answer 24

Nephrotoxicity

Question 25

Side effect of rabacfosadine (tanovea)

Answer 25

Idiosyncratic pulmonary fibrosis

Question 26

Why is cisplatin contraindicated in cats?

Answer 26

It causes severe pulmonary vasculitis and oedema

Question 27

Weird side effects of hydroxyurea in cats and dogs

Answer 27

``` Dogs = claw detachment Cats = Methoglobinaemia ```

Question 28

MoA of hydroxyurea

Answer 28

It inhibits ribonucleotide reductase leading to a reduction in RNA pools available for new cell production. Therefore it is often used for myeloproliferative diseases and neoplasias.

Question 29

WHO staging of lymphoma in dogs

Answer 29

``` I = local lymph node involvement only II = regional lymphatic spread III = more generalised lymphatic spread IV = involvement of the liver and spleen V = bone marrow involvement a = without systemic signs b = with systemic signs ```

Question 30

Staging of lymphoma in cats

Answer 30

``` I = single extra nodal tumour or single anatomic area (nodal) II = same side of the diaphragm or resectable GI tumour (can have LN involvement) III = crossing of the diaphragm, paraspinal or epidural, or extensive/unresectable GI disease IV = stage 1-3 with liver and spleen involvement V = stages 1-4 with involvement of CNS or one marrow or both. ```

Question 31

How to differentiate thymic lymphoma vs. thymoma with flow cytometry.

Answer 31

Thymoma is more likely to be double positive for CD4 & CD8.

Question 32

Where does renal lymphoma tend to metastasise in cats?

Answer 32

CNS

Question 33

Where does GI lymphoma tend to metastasise to in cats?

Answer 33

Renal system.

Question 34

Most common neoplasia associated with pulmonary metastatic disease?

Answer 34

Mammary carcinoma.

Question 35

What is the other name for tignalol tigalate (Stelfonta)

Answer 35

EBC-46