Neoplasia Flashcards
Neoplasia Definition
New Growth, another term for cancer
What is neoplasia?
Neoplasia occurs when damage occurs to a cell that allows it to divide regardless of whether it is told to by other cells
What is oncology?
The study of neoplasia
What is cellular proliferation?
cells rapidly dividing
What are the four components of a neoplasm?
-divide at a faster rate
-not coordinated with surrounding tissue
-do not perform a function that supports the organism
-essentially like a parasite; it benefits from the support of other cells, but is detrimental to the organism as a whole
Why are neoplasms bad?
-They are not concerned with the organism as a whole.
-These growths do not perform a function that supports the function of the organism.
Tumor definition
swelling or growth; more often associated with being benign
Benign vs Malignant Overall Definitions
Benign- non-dangerous tumors
Malignant- invade and spread (dangerous tumors)
Key difference: malignant tumors are capable of invading and damaging the surrounding tissues and can spread to other parts of the body
What is cancer?
Cancer is a word most commonly used with malignant neoplasms.
Derived from the word “crab” from Greek physician, Hippocrates
Anaplasia
completely undifferentiated
What are the four key factors that determine whether a tumor is malignant or benign
- Differentiation
Benign- well-differentiated
Malignant- poorly-differentiated - Rate of Growth
Benign- Slow growth rate
Malignant- High growth rate - Local invasion
Benign- well-contained/encapsulated (fibrous tissue that keeps the tumor as a clearly defined mass); does not invade the tissues/structures surrounding them; rarely grows back once surgically removed
Malignant- not encapsulated; invades surrounding tissues/structures; difficult to have clarity where the edges are and cut out completely; can grow back if not completely removed - Metastasis
Benign- does not metastasize
Malignant- have the potential to metastasize
Well-differentiated
cells look similar to the surrounding cells
Poor-differentiated
cells look nothing like the surrounding cells
How is the rate of growth related to differentiation?
Well-differentiation (Benign tumors) grow more slowly/ have a lower rate of growth
Poor-Differentiation (Malignant tumors) grow quickly/ have a higher rate of growth
What is metastasis?
Cancer spread; tumors that appear in other parts of the body that are separate from the original or primary tumor; spread occurs by the bloodstream, lymphatic system, or body cavities; in most cases, it is impossible to cure once the cancer has spread
Adenoma
form of benign tumor that is glandular; theses can release hormones
ex. adenoma of the pituitary gland cause the release of hormones (Cushing’s disease)
Polyps
technically benign tumors but can also be precursors to malignant tumors
Are there ever any benign tumors of the brain?
any tumor in the brain cannot truly be considered benign; the skull is a fixed volume, so anything else inside will create pressure and cause various problems
*any type of brain tumor will cause an increase in pressure as they grow and start compressing parts of the brain
How do tumors develop?
Tumors develop from the proliferation of a single abnormal cells
How does damage to the cell’s DNA pass on to the following generation of tumor cells?
Transcription and Translation!
Transcription is changing the DNA to mRNA and translation to translating the code of the mRNA into proteins. Any mutation in the original DNA will pass on to the original cell’s daughter cells when it undergoes mitosis (or meiosis for sex cells)
The proteins that a cells makes determines the type of cell it is and what the cell does. If the DNA changes then the mRNA changes then the protein changes —> so the function of the cell ultimately changes
Is cancer a genetic disease?
Yes! Mutation occurs at the gene level; this doesn’t mean that it is hereditary
What properties does a cancerous cell have?
- Self-sufficiency in growth signals
- Insensitive to anti-growth signals
- Tissue invasion and metastasis
- Limitless replicative potential
- Sustained angiogenesis (stimulate new growth of blood vessels to supply bloody supply necessary for growth)
- Avoiding apoptosis (cell death)
