Sept. 23, 2019 Flashcards
Define NEOPLASIA
A process whereby new CELLS are formed
Are the CELLS formed during NEOPLASIA normal CELLS?
No, they are made through accelerated growth rates, something which almost always results in abn CELLS d/t lack of regulation during accelerated growth
What is a NEOPLASM?
a TUMOR, the result of NEOPLASIA, and abn mass of tissues/CELLS
Characterisitics of a MALIGNANT (CA) TUMOR?
- Rapid, disorderly growth
- need space
- mutated GENES
- CELLS undiff
- invasive, damaging, irreversible
What regulates CELL division and growth?
GENES
How do CA TUMORS make space for themselves to further expand growth?
They secrete ENZYMES into the surrounding tissue
Characteristics of a BENIGN TUMOR?
- Rapid growth, but less rapid than CA
- May be encapsulated
- non invasive
- differentiated CELLS
- May stop
What do GENES code for?
They code for PROTEINS
Can GENES actually carry out any of the actions they code for?
No, the PROTEINS are responsible for carrying out the actions intended by the GENES
What is the TP53 GENE responsible for?
APOPTOSIS if DNA is damaged, mutated in 50% of CA cases
What is the DNA repair GENE responsible for?
Repairing defective DNA, a primary target for CA
What is the PROTO-ONCOGENES (GO-GENE) responsible for?
Triggers CELL differentiation, promotes growth. Mutation results in excessive growth
What is the TUMOR SUPPRESSOR GENES (STOP GENE) responsible for?
Inhibit CELL growth. mutation results in excessive growth
e.g. TP53
What is the ONCOGENE responsible for?
These are GENES that cause CA, can be any GENE
A BENIGN TUMOR will usually end with what suffix?
OMA
A MALIGNANT TUMOR will end with the suffix _________ if it is of EPITHELIAL origin
CARCINOMA
A MALIGNANT TUMOR will end with the suffix _________ if it is of MESENCHYMAL origin
SARCOMA
What is an example of MESENCHYMAL tissue?
MESENCHYME is embrionic tissue, not found in adults, but it gives rise to all tissues in the body that are NON-EPITHELIAL
What would ADENOMA indicate?
“ADEN” indicates GLANDULAR EPITHELIUM, “OMA” indicates BENIGN, therefore this is a BENIGN TUMOR in GLANDULAR EPITHELIUM
What would ADENOCARCINOMA indicate?
“ADEN” indicates GLANDULAR EPITHELIUM, “CARCINOMA” indicates MALIGNANT TUMOR in EPITHELIAL tissue, therefore this is CA of GLANDULAR EPITHELIUM
Approximately how fast do TUMORS grow?
They approximately double in size every 120 days, take roughly 10 yrs before clinically detectable
What happens locally during the spreading of a TUMOR?
Invasion and extension (making room)
What is SEEDING? Where does it typically take place? Is this a local process?
SEEDING is a method by which CA CELLS spread to different parts of the body. Typically takes place in body cavities. This is not a local process.
Define METASTASIS
The development of secondary malignant growths at a distance from a primary site of cancer.
Where is the most common secondary site for METASTASIS to occur?
LYMPHATIC TISSUE
What are 5 other common secondary sites that METASTASIS generally occurs?
1) BONES
2) LIVER
3) LUNGS
4) BRAIN
What makes a site ideal for METASTASIS?
If it is relatively large and is richly PERFUSED
What happens during the 1st step in METASTASIS?
- Local growth and extension
- Will make contact w B and LYMPH
- Invades local tissue w ENZYMES
- EMBOLI (small groups of CELLS) enter B or LYMPH
- Less than 10,000 CELLS survive d/t IR and small numbers of CELLS
What happens during the 2nd step in METASTASIS?
- Passage via B or LYMPH
- Reach area of resistance
- Attach and proliferate at 2nd site aided by CYTOKINES and GFs
What happens during the 3rd step in METASTASIS?
- Determined suitable site
- Begin to proliferate and grow
- Angiogenesis
