-
What is neoplasia?
uncontrolled growth of cells whose proliferation cannot be adequately controlled by normal regulatory mechanisms in normal tissues
-
Why is cancer called "cancer"?
- latin word for crab
- tumors invade tissues like crawling crabs
-
What does the word tumor mean?
swelling
-
What are some other names for tumor?
-
What is oncology?
the study of neoplasia
-
What is the proliferation of normal cells regulated by?
- genetic program of each cell
- signals transmitted between cells by direct contact
- various soluble substances which have growth promoting or inhibiting effects
-
What happens once cells stop proliferating?
they assume specialized functions by activating specific genes and suppressing unneeded genes
-
Do cancer cells usually achieve the same level of differentiation as normal cells?
no
-
Describe the growth of a tumor cell.
- autonomous
- excessive
- disorganized
-
How is the growth of a tumor cell autonomous?
independent of growth factors and stimuli that promote the growth of normal cells
-
How is the growth of a tumor cell excessive?
do not respond to normal regulations of cell proliferation - growth does not stop
-
How is the growth of a tumor cell disorganized?
random growth - does not try to form normal tissue
-
Can more than one type of neoplasia occur in an individual?
yes
-
Are all cells in a tumor neoplastic?
- no
- supportive elements are not neoplastic - connective tissue, blood vessels
-
What can interfere with the recognition of a tumor?
- hemorrhage
- necrosis
- inflammation
-
Can spontaneous regression of neoplasia occur?
yes
-
Can tumors develop from any cell type?
yes
-
What are the different types of neoplasia of the spleen?
- lymphosarcoma (lymphocytes)
- hemangiosarcoma (blood vessels)
-
What are the different types of neoplasia of the skin?
- melanomas (melanocytes)
- sebaceous adenomas (oil glands)
- lipomas (adipose cells)
-
Not all masses are neoplasms. What types of masses are not neoplastic?
- granulomas
- cysts
- abscesses
- hyperplastic nodules (spleen, prostate, mammary)
-
Not all neoplasms are masses. What are some neoplasms that are not masses?
- leukemia (malignant cells in circulation)
- diffuse infiltration or enlargement of an organ
-
Does the size of the tumor indicate the degree of malignancy?
- no
- tiny tumors can be malignant, large tumors can be benign
-
Can neoplasia be present as a non-healing lesion or as an ulcerated mass?
yes
-
Is neoplasia usually a different color from adjacent normal tissue?
yes
-
Can we identify neoplasia by a gross exam?
- no
- microscopic identification is needed
-
Why is important to identify the specific type of neoplasia?
for prognosis, treatment, and to predict the behavior of the tumor
-
What is the role of the LVT regarding neoplasia?
- recognize potential neoplasms (grossly and microscopically)
- may observe tumor cells in sediment cytology of urine, body cavity fluid, blood smears, aspirates
- prepare tissue for cytology
|
|