Cancer I Flashcards
What are solid mass neoplasms
Tumors
Characteristics of benign neoplasm
- noncancerous
- confined to limited area (circumscribed- covered in fibrous sheath)
- slower growth rate
- mass effect
Characteristics of potentially-malignant neoplasms and examples
- typically localized (does not invade surrounding tissues)
- may transform into a malignant neoplasm
ex- colorectal polyps
What are the two major characteristics of malignant neoplasms
Invasion- Direct extension and penetration into neighbouring tissues
Metastasis- spread to non neighbouring tissues via circulation/lymphatics
What are common metastatic sites
lymph nodes, lungs, liver, CNS, bones (possibility of curative tx is reduced when malignant neoplasms metastasize)
differences bw benign and malignant tumors
benign- grow more slowly, localized, tend to be encapsulated, have regular shapes
Malignant- Growth takes on amorphous shape with irregular borders. grow faster
what is the most common general type of cancer and what is it derived from
carcinoma- cancers derived from epithelium
what is a sarcoma
cancers that arise from connective tissue or muscle
what is a blastoma
cancers of immature precursor cells
Difference bw leukemia, lymohoma, myeloma
leukaemia- in blood or bone marrow
Lymphoma- in lymphoid tissues
myeloma- plasma cells
3 stages of carcinogenesis
- Initiation- cell exposed to appropriate doses of carcinogenic agents rendering an irreversible genetic change
- Promotion- Proliferation of transformed cell (chance of control @ this stage)
- progression- acquisition of malignant characteristics (metastasis, proliferation)
What are examples of carcinogens
-Cigarete smoke
-alcoholic bevs
-infections
-UV radiation
asbestos
obesity + diet
what % of cancers are caused by direct inheritance
5-10%
What is epigenetic alterations and how does it work
- alterations in gene activity without altering a genes DNA sequence
- addition/ removal of methyl or acetyl
cancers is associated w what type of methylation (on cancer suppressing + promoting genes)
Hyper methylation of cancer suppressing genes
Hypomethylation of cancer promoting genes
What are protoonco genes/ oncogenes (+ ex)
proto0ncogenes- normal genes w important cell functions
Oncogenes- Malfunctuned oncogenes that contribute to uncontrolled cell proliferation (HER2/Kras)
What are tumor suppressor genes and examples
negative regulate cell division, DNA repair and genes that activate apoptosis
> 50% of cancers contain p53 mutations
(BRCA1/2)
What is the greatest risk factor for cancer
age >50
What are some biological properties of cancer cells
- growth factor independednt (don’t need signals to proliferate)
- Loss of density dependent inhibition (will still proliferate if crowded)
- Tendency to break free from tissues
- limitless replicative pot
what angiogenic growth factors can cancer cells release
Epidural growth factor
Transforming growth factor beta
mc cancers in canada (+ for genders)
-skin cancer mc
m=prostate
f=breats
children- hematological cancers
What are paraneoplastic syndromes
Clinical manifestations of cancer that occur in sites not directly affected by the malignant neoplasm
ex. clotting factors, hormones produced by the neoplasm
What is the cancer staging system (what does each stand for)
TNM system
T- How large is the primary neoplasm/ degree of invasion
N- Has the tutor speed to lymphocytes nodes
M-has the cancer spread to a non continuous site and to what extent (stage IV)
