Neoplasia

Question 1

Neoplasm

Answer 1

An abnormal mass of tissue, whose uncoordinated and excessive growth exceeds that of normal tissues and persists after the cessation of the initial stimulus.

Question 2

Are tumors autonomous?

Answer 2

Yes, but they depend on the host for nutrition.

Question 3

Characteristics of Benign Tumors

Answer 3

Cohesive, slow/limited growth, well circumscribed, lobulated, encapsulated, mobile.

Question 4

How can benign tumors be lethal?

Answer 4

If they’re in very sensitive areas like the heart (atrial myxoma) or the brain (meningioma).

Question 5

Characteristics of malignant tumors

Answer 5

Aggressive and limitless growth, invasion/destruction of adjacent structures, poorly demarcated. Infiltrating borders.

Question 6

How are neoplasms named?

Answer 6

Named for the tissue they are becoming, or for the tissue from which they are derived.

Question 7

Leiomyoma, and cancerous equivalent

Answer 7

Smooth muscle benign tumor. Leiomyosarcoma.

Question 8

Adenoma and cancerous equivalent

Answer 8

Glandular epithelium benign tumor, adenocarcinoma.

Question 9

Hamartoma

Answer 9

Disorganized growth of indigenous tissue. Ex: disorganized bile ducts in the liver

Question 10

Choristoma

Answer 10

Normal architecture in the wrong location, happens during development. Ex: heterotopic pancreas in the stomach.

Question 11

Parenchyma vs Stroma

Answer 11

P: The tumor. S: supporting cells and connective tissue.

Question 12

Hyperplasia

Answer 12

Increase in the number of cells.

Question 13

Metaplasia

Answer 13

Replacement of one mature cell type with another. Ex: Columnar to squamous in the lungs of smokers.

Question 14

Dysplasia

Answer 14

Loss of cell uniformity and orientation. Generally with epithelium, where the cells grow in number. First sign on way to malignant neoplasm.

Question 15

Desmoplasia

Answer 15

A collagenous fibrosis reaction to invasion.

Question 16

Anaplasia

Answer 16

Complete lack of differentiation. Certainly a malignancy.

Question 17

Grading of Neoplasms

Answer 17

Assigning a level of differentiation. Grade predicts future behavior.

Question 18

Criteria for determining grade

Answer 18

Uniformity, nuclei, mitoses, architecture

Question 19

What is abnormal about cancer cell nuclei?

Answer 19

They are enlarged and elongated, hyperchromatic, increased nucleus to cytoplasm ratio. Prominent nucleoli.

Question 20

What is abnormal about cancer cell uniformity?

Answer 20

Pleomorphism: large variation in size and shape.

Question 21

What is abnormal about cancer cell mitoses?

Answer 21

Higher number relative to healthy cells. Atypical shapes of mitotic cells. Sometimes tripolar.

Question 22

What is abnormal about cancer cell architecture?

Answer 22

Loss of polarity and luminar orientation.

Question 23

Clinically detectable rate of tumor growth vs rate that’s incompatible with life

Answer 23

10^9 (30 doublings) vs 10^12 (40 doublings)

Question 24

Rate of tumor growth dependent on…

Answer 24

Doubling time, growth fraction (% of neoplastic cells dividing), rate of cell loss. Growth fraction most important.

Question 25

Susceptibility to chemotherapy determined by...

Answer 25

Growth Fraction.

Question 26

How does surgery affect growth fraction?

Answer 26

Increases it! Increasing susceptibility to chemo.

Question 27

What is easier to resect, benign or malignant growth?

Answer 27

Benign, good borders. Malignant tumors have terrible borders and cause a desmoplastic response if they have infiltrated surrounding tissue, increasing collagen and fibrous tissue.

Question 28

Carcinoma in situ

Answer 28

Dysplasia that involves that entire thickness of epithelium. Seen generally in the cervix, the thin squamous cells at the top are replaced by rounded cells all the way through.

Question 29

Metastasis

Answer 29

Remote tumor deposits, a keystone feature of malignant tumors. Correlates with tumor grade

Question 30

3 means of metastasis

Answer 30

Lymphatic spread- carcinomas spread through regional lymph nodes. Hematogenous spread- through vessels, generally to liver and lungs. By both carcinomas and sarcomas. Seeding of cavities- pleura and peritoneum, carcinomas.

Question 31

Tumor Staging

Answer 31

T (Size of primary tumor, 0-4), N (number/location of regional nodes), M (metastases, number sites). More important for prognosis than grading.

Question 32

Paraneoplastic syndrome

Answer 32

A comorbidity of cancer, unrelated to the tumor's location.

Question 33

Trousseau Syndrome

Answer 33

Causes venous thrombosis and a hypercoagulable state. Found with cancers like pancreatic carcinoma.

Question 34

What tumor suppressor is lost leading to polyp formation?

Answer 34

APC

Question 35

When is p53 lost? What is the consequence?

Answer 35

Usually late stage, causes development of full blown carcinoma.

Question 36

Things associated with invasion and metastasis

Answer 36

Loss of cadherins, ecm degradation by metalloproteases, increased attachment and migration, angiogenesis.

Question 37

Causes of skin cancer:

Answer 37

UVB exposure causes pyrimidine dimers.

Question 38

Cause of melanoma vs non-melanoma skin cancer

Answer 38

Intensity of light in melanoma, total exposure in non-melanoma.

Question 39

Cervical Squamous Cell Carcinoma caused by...?

Answer 39

HPV

Question 40

Cribiform

Answer 40

A gland within a gland