Exam 4: Neoplasia 2

Question 1

What are the direct effects of neoplasia?

Answer 1

Replace normal tissues
Compression of neighbor tissue
Obstruction or rupture
Disrupt anatomical relationships
Vascular compression/infiltration- infarction --> necrosis
Erosion of vessels- rupture, hemorrhage

Question 2

What are the paraneoplastic effects of neoplasia in the systemic system?

Answer 2

Anorexia/cachexia, fever

Question 3

What are the paraneoplastic effects of neoplasia in the endocrine system?

Answer 3

Hypercalcemia
Hypoglycemia
Hyperestrogenism
Thyrotoxicosis

Question 4

What are the paraneoplastic effects of neoplasia in the skeletal system?

Answer 4

Myelofibrosis

Hypertrophic osteopathy

Question 5

What are the paraneoplastic effects of neoplasia in the vascular/hematopoietic system?

Answer 5

Leukocytosis
Leukopenia
Anemia
DIC

Question 6

What are the paraneoplastic effects of neoplasia in the neruologic system?

Answer 6

Myasthenia gravis

Peripherial neuropathy

Question 7

What are the paraneoplastic effects of neoplasia in the cutaneous system?

Answer 7

Alopecia

Nodular dematofibrosis

Question 8

What can paraneoplastic effects facilitate?

Answer 8

Early tumor detection

Question 9

What is cachexia?

Answer 9

Weigh loss and debility associated with cancer
Muscle and fat are lost
No compensatory decrease in basal metabolism
Added caloric intake does bot alleviate
TNF-α, IL-1, IL-6

Question 10

What do thyroid carcinomas cause?

Answer 10

Hyperthyroidism

Question 11

What do pancreas islet cell carcinomas (insulinomas) of β cells cause?

Answer 11

Hyperinsuilinemia/hypoglycemia

Question 12

What is ectopic hormone production?

Answer 12

Production of hormone not normally found in tissue of origin

This is a paraneoplastic effect

Question 13

What causes hypercalcemia?

Answer 13

Parathyroid hormone-related peptide: humoral hypercalcemia of malignancy
Adenocarcinoma of the apocrine glands of the anal sac
Lymphoma
Multiple myeloma

Question 14

How does Parathyroid hormone-related peptide cause hypercalcemia?

Answer 14

It mimics the function of PTH, inducing calcium release from bone, reabsorption from kidneys, and absorption from intestine

Question 15

What are the hematopoietic/vascular paraneoplastic effects?

Answer 15

Eosinophilia, neutrophilia, basophilia, mast cells- cytokines
Anemia- chronic disease, blood loss, bone marrow invasion, hemolysis
Thrombocytopenia- immune mediated, hemangiosarcoma
Gastric mast cell tumors- histamine release, ulcerations

Question 16

What are the hallmarks of cancer?

Answer 16

Avoiding immune destruction
Evading growth suppressors
Enabling replicative immortality
Tumor-promoting inflammation
Activating invasion and metastasis
Genomic instability
Inducing angiogenesis
Resisting cell death
Deregulating cellular energetics
Sustaining proliferative signaling

Question 17

What are heritable alterations to neoplasia?

Answer 17

A progressive accumulation of genetic and epigenetic abnormalities

Question 18

What do heritable alterations lead to?

Answer 18

Cell growth, death, differentiation, DNA repair

Question 19

What are cancer phenotypes due to?

Answer 19

DNA mutations
Epigenetic changes
Chromosomal alterations

Question 20

What is karyotype?

Answer 20

Number and arrangement of chromosomes

Question 21

What are telomeres?

Answer 21

Terminal DNA sequences that protect cells from DNA damage

Question 22

What are molecular determinants of neoplasia?

Answer 22

Driver mutations (oncogenes, tumor suppressor genes)
Multiple changes needed for neoplasia to occur
Proto-oncogenes
Mutation leads to overexpression (oncogene) and cells become less responsive to inhibitory signals

Question 23

What are proto-oncogenes?

Answer 23

Normal genes that regulate growth

Question 24

What is a tumor suppressor gene?

Answer 24

Genes that control cell cycle, apoptosis, DNA repair

Question 25

What is p53?

Answer 25

A tumor suppressor gene that is commonly mutated in cancer

Question 26

What happens to a cell with a normal p53?

Answer 26

DNA damage increases p53 levels Transcription dependent and independent p53 effects on targets p21 is upregulated causing G1 to arrest, GADD 45 directs DNA repair or causes apoptosis with no DNA repair, and BAX upregulation causes apoptosis

Question 27

What happens to a cell with p53 mutation or loss?

Answer 27

DNA damage No p53 activation No cell cycle arrest, DNA repair, sensescence, or apoptosis Mutant cells are produced Expansion and additional mutations leading to a malignant tumor

Question 28

What causes carcinogenesis?

Answer 28

Chemicals

Question 29

What is direct carcinogenesis?

Answer 29

Effective in causing damage in the form encountered

Question 30

What is indirect carcinogenesis?

Answer 30

Require metabolic activation in the body

Question 31

What is radiation?

Answer 31

A complete carcinogen (can initiate and promote)

Question 32

What are examples of oncogenic viruses?

Answer 32

Feline leukemia virus (leukemia/lymphoma) Bovine leukemia virus (leukemia/lymphoma) Feline immunodeficiency virus (lymphoma) Poxviruses

Question 33

What are round cell tumors?

Answer 33

``` Histiocytoma Cutaneous lymphoma Plasmacytoma Mast cell tumors Transmissible venereal tumors ```

Question 34

What are histiocytomas?

Answer 34

``` Only in dogs (most common skin tumor) Young Rapid growth, button-like Skin around head most common Spontaneous regression Round to oval cells Oval nuclei, fine chromatin Abundant pale blue cytoplasm, few vacuoles Ulcerated/alopecici Junctional activity/epitheliotropism ```

Question 35

Describe cutaneous lymphoma

Answer 35

Can be epitheliotropic (mycosis fungoides) or nonepitheliptrophic B and T cells Large cells, abundant cytoplasm, nucleoli

Question 36

Describe plasmacytoma

Answer 36

Benign, older dogs, head feet Rarely functional Round cells, dense, chromatin, 1-3 nuclei Abundant blue cytoplasm, prominent Golgi zone

Question 37

Describe mast cell tumors

Answer 37

``` Nodules, well circumscribed or poorly defined/edematous Solitary or multiple Older dogs All are potentially malignant Dermal (graded) Subcutaneous Eosinophils Abundant metachromatic cytoplasmic granules ```

Question 38

What is an example of transmissible tumors?

Answer 38

Transmissible venereal tumor of dogs

Question 39

Describe transmissible venereal tumor of dogs

Answer 39

Direct physical spread/contact Cells in all tumors have similar genetic and cytologic character that differ from the host (dog) A single tumor that disseminated to multiple hosts

Question 40

Which cells produce tumors?

Answer 40

Undifferentiated stem cells

Question 41

How many cells does it take to produce a tumor?

Answer 41

1

Question 42

What are the angiogenesis factors?

Answer 42

Vascular endothelial growth factor TGF-β Angiogenin

Question 43

How do RNA viruses make tumors?

Answer 43

RNA viruses transcribe RNA backwards into DNA using reverse transcriptase. They insert that DNA copy of the viral genome in the host DNA - a provirus. They steal the genes from the cell and turn them into oncogenes or tumor genes

Question 44

How do DNA viruses make tumors?

Answer 44

No stolen oncogenes are associated with DNA viruses, but they may carry genes that code for transforming genes

Question 45

What is carcinomatosis?

Answer 45

The diffuse seeding or spread via lymphatics of carcinomas on serosal surfaces