Lecture 4

Question 1

What does carcinogenic mean

Answer 1

Agent that causes mutations resulting in tumor formation

Question 2

What is oncology

Answer 2

The study of neoplasia (diagnosis, treatment)

Question 3

What are the characteristics of benign neoplasm

Answer 3

Well differentiated
The cells resemble closely the parent tissue
Little or no anaplasia
Slow growth
No basement membrane invasion
Do not metastasize
Often encapsulated

Question 4

How can a benign neoplasm cause disease

Answer 4

By compressing sensitive tissues
By being metabolically active
By malignant transformation

Question 5

What are the characteristics of malignant neoplasm

Answer 5

Some lack of differentiation
Anaplasia
Rapid Growth
Many mitotic figures
Abnormal mitotic figures
Locally invasive
Infiltrative growth
Frequent metastasis
Usually no capsule

Question 6

What are some names of epithelial tumors

Answer 6

Adenoma
Papilloma
Carcinoma
Adenocarcinoma

Question 7

What are some names of mesenchymal tumors

Answer 7

Tissue -oma

Tissue -sarc0ma

Question 8

How does a tumor metastasise

Answer 8

Invasion of host tissue
Dissemination through vascular system
Implantation on new surfaces

Question 9

What are some diagnostic methods for neoplasm

Answer 9

radiology
computed tomography
ultrasound
MRI
Nuclear Medicine
cytology
DNA, RNA analysis

Question 10

What do you do radiography for

Answer 10

screening test

Question 11

why do you use computed tomography

Answer 11

to characterize and localize lesion
identify metastasis
surgery and radiotheraphy planning

Question 12

Why do we use ultrasound

Answer 12

Abdomen: internal structure of organs and to image body cavities when effusion
Assess vasculature
Ultrasound-guided sampling

Question 13

Why do we use nuclear medicine

Answer 13

administration of radioisotopes

Question 14

What are the advantages to cytology

Answer 14

Relatively low risk of procedures to the animal
Lower cost compared with biopsy
Speed with which results can be obtained
Best to evaluate cellular criteria (ex lymphoma)

Question 15

what are the disadvantages to cytology

Answer 15

Small sample (may not be representative)
No tissue architecture

Question 16

Why do we do DNA and RNA analysis

Answer 16

Study mutations to help classify tumors
Diagnostic utility (lymphocytosis)
Can help guide therapy

Question 17

Why do we do grading

Answer 17

Done to predict/classify the behavior of the tumor.
Different criteria depending on tumor type.
Done by pathologist

Question 18

Why do we do staging

Answer 18

Describing or classifying a cancer based on the extent of cancer in the body.
Often based on the size of the tumour, presence of metastasis
Stages are based on specific factors for each type of cancer

Question 19

What are some clinical effects of neoplasm

Answer 19

The pressure exerted by the neoplasm on the surrounding tissues will cause the following effects:
Pain
Vessels blockage
Dyspnea, hypoxia
Compromise organ function

Question 20

What is cachexia

Answer 20

Weakness and wasting of the body due to severe chronic illness
that cannot be reversed nutritionally
Inflammatory cytokines involved

Question 21

What causes anemia

Answer 21

Suppression of erythropoietin synthesis in kidneys
Hemorrhages
Decreased erythropoiesis
Erythrocyte fragmentation

Question 22

What causes hypercalcemia

Answer 22

Tumor cell secretions

Osteolytic metastases of neoplasms

Question 23

What are some causes of cancer

Answer 23

Genetic
 Immunosuppression
 Chemical carcinogens
 Viral carcinogens
 Physical carcinogens
 Chronic tissue injury

Question 24

What are some environmental factors that cause cancer

Answer 24

Cigarette smoke
Ultraviolet irradiation
Urbanization
Diet

Question 25

What are the intrinsic factor that cause cancer

Answer 25

Oxygen free radicals that result from chronic inflammation Intrinsic errors in DNA replication every time a cell divides, each daughter cell is likely to carry at least a few hundred mutations in its DNA Most are silent, but accumulate

Question 26

describe heritable cancer syndromes

Answer 26

Cancers with clear heritable basis | Not many described in veterinary literature

Question 27

Describe genetic Influence in Sporadic Cancers

Answer 27

It is Why not all smokers get lung cancer

Question 28

Describe Presence of distinct heritable traits that segregate with common cancer phenotypes in dogs (animals)

Answer 28

Will not cause cancer directly (unlike heritable syndrome) | Histiocytic sarcoma in Bernese Mountain dogs

Question 29

What are the characteristics of the chemical extrinsic factors

Answer 29

``` Very wide variety Most bind covalently to DNA Direct carcinogen Indirect: Require metabolic activation ```

Question 30

what are the characteristics of the physical extrinsic factors

Answer 30

``` Sunlight facial, aural, and nasal planum SCC in white or partially white cats and may also play a similar role in some cutaneous SCC lesions in dog Trauma/Inflammation Chronic keratitis Feline vaccine associated sarcoma Radiation At site of radiation therapy Surgery/Implants Anecdotal reports ```

Question 31

what are the characteristics of the hormonal extrinsic factors

Answer 31

Canine mammary cancer most common neoplasm of female intact dogs Similar in cats, but not as well documented Perianal adenoma occurs primarily in intact male dogs, whereas perianal adenocarcinoma occurs in both intact and castrated males Resolves after castration Prostate cancer neutered dogs have been shown to be at increased risk

Question 32

Describe the papilloma virus

Answer 32

Usually multiple lesions affecting young dogs | Most regress without txt

Question 33

Describe the feline leukaemia virus

Answer 33

Still much to discover Only 20% of cats persistently infected with FeLV develop lymphoid cancer Twenty years ago, 70% of lymphomas in cats were believed to be caused by FeLV

Question 34

describe the FIV virus

Answer 34

neoplasms most commonly linked to FIV infection Lymphomas and myeloid tumors (myelogenous leukemia, myeloproliferative disease) few carcinomas and sarcomas Lentiviruses such as FIV not oncogenic in themselves markedly immunosuppressive affect normal immunosurveillance of cancerous cells

Question 35

Describe canine hemangiosarcoma

Answer 35

Highly malignant neoplasm that originates from vascular endothelium Affects middle-age to older dogs, large breed Primary tumor site: Spleen Heart (right atrium) Subcutis Liver Metastasis: lungs, liver, mesentery, and omentum (hematogenous) Direct spread Features helpful for diagnosis (pertinent staging/grading, etc): Often morphologically altered RBCs are present, such as schistocytes, acanthocytes, and poikilocytes Can present as acute abdomen or cardiac tamponade Other (complications, prognosis, etc) Highly metastatic Watch for DIC If Splenic, need to remove spleen, but prognosis still poor (better with chemo - 141–179 days)