Path: Epidemiology and Classification of Neoplasia

Question 1

What is heterotopia?

Answer 1

congenital anomaly characterized by normal tissue in an abnormal location

Question 2

What is metaplasia?

Answer 2

replacement of one cell type with another cell type.

Question 3

What is dysplasia?

Answer 3

abnormal growth- pre-neoplastic change seen in the epithelia

Question 4

What is a benign neoplasia?

Answer 4

localized neoplasm that cannot spread to other sites

Question 5

What is a malignant neoplasia?

Answer 5

cancer. Can invade locally and spread to distant sites

Question 6

What is anaplasia?

Answer 6

A lack of differentiation within a tumor.

Question 7

What terminology surrounds benign neoplasms?

Answer 7

typically end in -oma.

Question 8

What terminology is used to describe malignant mesenchymal neoplasms?

Answer 8

end in -sarcoma

mesenchymal refers to connective tissue

Question 9

What terminology is used to describe malignant epithelial neoplasms?

Answer 9

carcinoma

Question 10

What is lymphoma?

Answer 10

malignant neoplasm of lymphocytes

Question 11

What is melanoma?

Answer 11

malignant neoplasm of melanocytes

Question 12

What is mesothelioma?

Answer 12

malignant neoplasm of mesothelium

Question 13

What is seminoma?

Answer 13

malignant neoplasm of the seminiferous tubules

Question 14

What is choristoma?

Answer 14

heterotopia- normal tissues found in abnormal locations

Question 15

What is hepatoma?

Answer 15

old term for hepatocellular carcinoma

Question 16

What are four features typically used to help distinguish between benign and malignant neoplasms?

Answer 16

differentiation and anaplasia
rate of growth
local invasion
metastasis

Question 17

What are some features associated with lack of differentiation?

Answer 17

1. pleomorphism- variation in size and shape; lack of uniformity
2. abnormal nuclear morphology: hyperchromasia, increased N:C ratio, irrecular nuclear contours, course chromatin; large nucleoli
3. mitosis/atypical mitosis
4. loss of polarity
5. tumor giant cell formation
6. necrosis

Question 18

What are three pathways for metastatic dissemination?

Answer 18

1. direct seeding (ie. colon cancer grows through serosa and seeds peritoneal cavity)
2. lymphatic
3. hematogenous

Question 19

How much of cancer risk is thought to be attributable to the environment?

Answer 19

2/3

Question 20

What are three genetic sources for cancer risk?

Answer 20

1. autosomal dominant cancer syndromes: mutations in tumor suppressor genes
2. defective DNA repair
3. familial cancer: high freq. of cancer in a family w/o a clearly defined tansmission pattern. potentially due to multiple low penetrance alleles

Question 21

What are three examples of chronic inflammation as a non-hereditary predisposing condition for cancer?

Answer 21

H. pylori, chronic viral hepatitis C infection, and ulcerative colitis

Question 22

What kinds of genes are usually mutated in cancer?

Answer 22

1. oncogenes
2. tumor suppressor genes
3. genes that regulate apoptosis
4. DNA repair genes

Question 23

What are 7 changes that happen with malignancy?

Answer 23

1. self-sufficiency in growth signals
2. insensitivity to growth inhibitory signals
3. evasion of apoptosis
4. limitless replicative potential
5. sustained angiogenesis
6. ability to invade and metastasize
7. defective DNA repair

Question 24

What are some ways in which a cell might acquire self-sufficiency in growth signals?

Answer 24

overproduction of growth factor and a switch from paracrine to autocrine
mutations or overexpressions of growth factor receptors that allow them to dimerize and activate in the absence of growth factor binding. HER2 receptor gene amplification in breast/gastric cancers is an example.

Question 25

What are examples of activation of signal transducers?

Answer 25

RAS genes are an example. point mutations most common abnormality of proto-oncogenes

Question 26

How do tumor suppressor genes contribute to growth?

Answer 26

tumor suppressor mutations lead to an insensitivity to growth inhibition

Question 27

What are some of the steps required for metastasis?

Answer 27

``` get through the ECM get through the serosa survive interactions with lymphocytes extravasation angiogenesis in new site growth ```

Question 28

What mutation is involved in HNPCC?

Answer 28

(hereditary nonpolyposis colorectal cancer) aka lynch syndrome. mutation in DNA mismatch repair enzymes.

Question 29

How might epigenetic changes lead to cancer?

Answer 29

hypermethylation might silence critical tumor suppressor genes

Question 30

How might immune cells promote cancer?

Answer 30

1. pro-survival and pro-proliferation cytokines 2. may promote switch from vascular quiescence to angiogenesis 2. tumor infiltrating macrophages may promote metastasis, potentially by chemotactic migration of tumor toward the vasculature.

Question 31

To what does immuno-editing refer?

Answer 31

immune system may play a role in selecting tumor variants that have reduced immunogenicity

Question 32

Why do we think the immune system might combat cancer (the evidence- 4 reasons)

Answer 32

lymphocytic infiltrates are seen around cancer, transplanted tumors don't always survive well, incr. incidence of cancer in the immunocompromised, tumor-specific T cells and antibodies

Question 33

What are some potential tumor antigens? (5)

Answer 33

mutated gene products, overly expressed proteins, oncogenic virus proteins, fetal proteins expressed in an adult, alter glycolipids/proteins

Question 34

What are 4 antitumor mechanisms?

Answer 34

1. cytotoxic T cells 2. natural killer cells 3. macrophages (ROSs) 4. antibodies (in therapy)

Question 35

What are 6 ways that tumor cells evade the immune system?

Answer 35

1. antigen-neg variants 2. reduced MHC expression 3. lack of costimulation leading to T cell apoptosis 4. immunosuppression (TGF-beta) 5. antigen masking 6. induction of apoptosis of T cells

Question 36

What is one example of a therapeutic anti-tumor vaccine? How does it work?

Answer 36

provenge for metastatic prostate cancer stimulates an immune response to prostatic acid phosphatase (PAP). must be customized to each patient. APCs are cultured with PAP and reinfused into patient.

Question 37

How might benign neoplasms have catastrophic effects (4)?

Answer 37

location (ie. in the brain) hormone synthesis bleeding infection

Question 38

What is cachexia? Why is it important?

Answer 38

cachexia: loss of body fat and lean body mass associated with profound weakness, anorexia, and anemia. unexplained by nutritional demands of the tumor, but may be related to cytokine production. May limit therapeutic options.

Question 39

What is paraneoplastic syndrome?

Answer 39

symptom complex not explained by local or distant spread of tumor or elaboration of hormones. May be lethal; may be earliest manifestation of the tumor.

Question 40

What are some examples of paraneoplastic syndromes?

Answer 40

pancreatic cancer that promotes venous thrombosis; gastric and bronchogenic cancers that promote overly robust immunloogic responses.

Question 41

What is tumor grade?

Answer 41

degree of differentiation- specific for each cancer type. usually 2-4 tiers.

Question 42

What is tumor stage? What is it used for?

Answer 42

used to predict prognosis and make treatment decisions.

Question 43

In what ways are tumor markers useful?

Answer 43

generally useful for detecting recurrence but not for definitive diagnosis.

Question 44

What are four sampling techniques?

Answer 44

1. excisional biopsy (cut all the way around the lesion and send to path) 2. incisional biopsy 3. fine needle aspiration 4. exfoliative smear (pap smear)