Cell Growth and Neoplasia Flashcards
Give examples of human cells with different hemostatic states
continuously dividing cells: epithelium
quiescent tissues: normally little turnover: liver cells
non-dividing cells: CNS
What are some cell intrinsic mechanisms of maintenance?
Differentiation program, age of cell
What are some cell extrinsic (microenvironment) mechanisms of maintenance?
ECM/ “stroma”, growth factor and inflammatory milieu
What are some cell extrinsic (macroenvironment) mechanisms of maintenance?
Circulating factors: cytokines, hormones
What are some external environmental interactions?
Physical environment, infectious agents, inhaled substances
Give an example of hypertrophy
pregnant uterus
pathologic: hypertensive cardiac hypertrophy
Give an example of hyperplasia
mammary gland at puberty
pathologic: endometrium
Give an example of metaplasia
=change from one benign, differentiated cell type to another, usually in response to injury (eg: inflammation)
bronchial squamous metaplasia, esophageal columnar metaplasia
What are characteristics of dysplasia
=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)
Which of the following are associated with an increased risk of neoplasia?
a. Hypertrophy
b. hyperplasia
c. metaplasia
d. dysplasia
All except for hypertrophy
What are the features of a benign neoplasm?
circumscribed/encapsulated
necrosis uncommon
well differentiated
cytologic uniformity (cells similar to eachother)
border between adjacent tissue is maintained
What are the features of a malignant neoplasm?
necrosis common variable differentiation high turnover cytologic pleomorphism general loss of boundary between adjacent tissue
Where is there highest risk for injury by a benign neoplasm?
Brain!
Cause injury by compression or interference of function of adjacent cells
What is the original meaning of “tumor”?
Swelling
About how many Americans will get cancer? How many will die from it?
About 1 in 2 americans will get cancer
1 in 5 will die from it
What non-genetic factors can cause cancer?
- age
- lifestyle
- environment
- occupational hazards
- radiation
- infection
- inflammation
What are some characteristics of cancer pathobiology?
- 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
How are tumors classified?
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
How is the histologic grade used?
=degree of tumor histologic differentiation
Low grade > more differentiation/ resemblance to normal cells
High grade > less differentiation/ resemblance to normal cells
What are some rule breakers to the carcinoma TNM classification?
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
How are pediatric neoplasms different from adults?
- Originate in developmental precursors
- short latency and early metastasis
- fewer mutations
- relative chemosensitivity (at a price)
