Cell Growth and Neoplasia

Question 1

Give examples of human cells with different hemostatic states

Answer 1

continuously dividing cells: epithelium

quiescent tissues: normally little turnover: liver cells

non-dividing cells: CNS

Question 2

What are some cell intrinsic mechanisms of maintenance?

Answer 2

Differentiation program, age of cell

Question 3

What are some cell extrinsic (microenvironment) mechanisms of maintenance?

Answer 3

ECM/ “stroma”, growth factor and inflammatory milieu

Question 4

What are some cell extrinsic (macroenvironment) mechanisms of maintenance?

Answer 4

Circulating factors: cytokines, hormones

Question 5

What are some external environmental interactions?

Answer 5

Physical environment, infectious agents, inhaled substances

Question 6

Give an example of hypertrophy

Answer 6

pregnant uterus

pathologic: hypertensive cardiac hypertrophy

Question 7

Give an example of hyperplasia

Answer 7

mammary gland at puberty

pathologic: endometrium

Question 8

Give an example of metaplasia

Answer 8

=change from one benign, differentiated cell type to another, usually in response to injury (eg: inflammation)

bronchial squamous metaplasia, esophageal columnar metaplasia

Question 9

What are characteristics of dysplasia

Answer 9

=proliferation of cells of abnormal type, “disordered growth”

loss of cytologic uniformity, loss of normal maturation, loss of architectural orientation

usually assigned histologic grade (low vs. high)

Question 10

Which of the following are associated with an increased risk of neoplasia?

a. Hypertrophy
b. hyperplasia
c. metaplasia
d. dysplasia

Answer 10

All except for hypertrophy

Question 11

What are the features of a benign neoplasm?

Answer 11

circumscribed/encapsulated
necrosis uncommon
well differentiated
cytologic uniformity (cells similar to eachother)
border between adjacent tissue is maintained

Question 12

What are the features of a malignant neoplasm?

Answer 12

necrosis common
variable differentiation
high turnover
cytologic pleomorphism
general loss of boundary between adjacent tissue

Question 13

Where is there highest risk for injury by a benign neoplasm?

Answer 13

Brain!

Cause injury by compression or interference of function of adjacent cells

Question 14

What is the original meaning of “tumor”?

Answer 14

Swelling

Question 15

About how many Americans will get cancer? How many will die from it?

Answer 15

About 1 in 2 americans will get cancer

1 in 5 will die from it

Question 16

What non-genetic factors can cause cancer?

Answer 16

• age
• lifestyle
• environment
• occupational hazards
• radiation
• infection
• inflammation

Question 17

What are some characteristics of cancer pathobiology?

Answer 17

• self sufficiency in growth signals
• insensitivity to anti-growth signals
• tissue invasion and metastasis
• limitless replication potential
• sustained angiogenesis
• evading apoptosis
• clonal evolution > proliferation gives tumor cell variants heterogeneity

Question 18

How are tumors classified?

Answer 18

TNM classification (for carcinomas)

• T: tumor (how much has it evaded into tissue)
• N: Lymph nodes
• M: Distant metastasis

The higher the numbers associated with each letter, the worse the prognosis

Question 19

How is the histologic grade used?

Answer 19

=degree of tumor histologic differentiation

Low grade > more differentiation/ resemblance to normal cells

High grade > less differentiation/ resemblance to normal cells

Question 20

What are some rule breakers to the carcinoma TNM classification?

Answer 20

It doesn’t apply to the pre-malignant lesion or in-situ phases of sarcomas, lymphomas, and CNS neoplasms (see chart from his slides)

Pediatric neoplasms

Question 21

How are pediatric neoplasms different from adults?

Answer 21

• Originate in developmental precursors
• short latency and early metastasis
• fewer mutations
• relative chemosensitivity (at a price)