introduction to cancer Flashcards
what is a carcinoma
a type of cancer that starts in the epithelial tissue of the body, which lines the inside and outside of the body
form approx 85% of cancers
why does cancer risk increase with age
because cells accumulate damage over time, making them more likely to become cancerous
as cells replicate, mutation(erros) occur too. with age, more cells have replicated, and more mutations occur rendering it more likely for cancer to occur.
cancer is a multi-step process true or false
true
neoplasm
an abnormal growth of tissue or mass of cells in the body, also known as a tumor
neoplasia= new growth
the two main tumour types
benign and malignant
benign= non cancerous , normally end in just “oma”
tumours indicated in cells with their names ending in “oma” like lymphoma, carcinoma…etc
some differences between benign and malignant tumours
note that some benign tumours can become malignant
benign tumours;
usually small
slow growing
non-invasive(do not invade surrounding tissue)
encapsulated
they stay localised
eradicated by surgery
do not tend to relapse
well differenciated
while for malignant;
they are large when advanced
fast growing
invasive
non-encapsulated
poorly differentiated(difficult to tell the tissue from which the tumour originates)
can spread
surgery not sufficient often
tend to relapse
malignant tumours often referred to as cancer
An encapsulated tumor is a tumor that is surrounded by a thin layer of tissue and is confined to a specific area
some examples of benign tumours
Adenoma – benign tumour arising from glandular cells
Leiomyoma – benign tumour arising from smooth
muscle cells
Chondroma – benign tumour arising from chondrocytes
Papilloma – has finger-like projections
Polyp – projects upward, forming a lump
Cystadenoma – has hollow spaces (cysts) inside
Fibroma – fibrous or connective tissue
Fibroadenoma – mixed characteristics
chrondocytes are cells that create cartilage, a flexible connective tissue that protects bones at joints and provides structural support
some examples of malignant tumours
carcinomas like adenocarcinoma, Squamous cell carcinoma, Basal cell carcinoma & Melanoma
sarcomas like Chondrosarcoma, Angiosarcoma, Rhabdomyosarcoma(affects skeletal tissue)
angioma(benign) or angiosarcoma(malignant) affect blood vessels
in which tissue do sarcomas arise from
mesynchymal tissue eg Bone, cartilage, vessels, muscles, fat
name some lymphoid and haemopoietic neoplasms and which cells they affect
Lymphocytes Lymphoma OR Leukaemia*
Granulocytes Myeloid leukaemia
Marrow lymphocytes Lymphocytic leukaemia
Plasma cells Multiple myeloma
leukaemia is a cancer that affects the bone marrow, but is not characterised by a solid tumour. leukaemia does not just affect WBCs, can affect various blood cell types including RBCs
some key causes of cancer
meat
alcohol
infections like oncoviruses
ionising radiation
sun exposure and sunbeds
tobacco
lack of fibre
obesity
lack of fruits and vegs
post menopausal causes…etc
most of these can also act as risks of cancer
state some of the mechanisms of action of carcinogenic chemicals
some act as ;
base analogues , substituting for DNA bases and causing copying erros
deaminating agents, by deaminating the DNA bases
intercalating agents
alkylating agents , by donating akly groups to other molecules
hydroxylating agents, by adding a hydroxyl group to the DNA base cytosine, cause a G:C to A:T transition
what are the following deaminated to?
cytosine
adenine
guanine
5-methylcytosine
Deamination of cytosine converts it into uracil
* Deamination of adenine converts into hypoxanthine
* Deamination of guanine converts into thymine
* 5-methylcytosine into thymine
how does ionising radiation increase cancer risk
damages DNA by breaking DNA strands, generating free radicals and causing chromosomal abnormalities
the two different types of skin cancer
malignant melanoma and non-melanoma skin cancer
the difference is in the cells that each of them affects. melanoma affects melanocytes while non-melanoma affects basal cells and squamous cells
non melanoma more prevalent in the uk but melanoma more fatal
melanoma the least common type of skin cancer
types or examples of non melanoma skin cancer
basal cell carcinoma
squamous cell carcinoma
BCC the most common type of skin cancer
the most common cancer causing additives found in processed meat
sodium nitrate
MSGs
which class of hormones are considered as “cancer promoters”
androgens or sex hormones, they are involved in prostate, breast, uterine and ovarian cancers
oral contraception increases the risk of which cancer
what other factor increases the risk of this particular cancer
break cancer
Hormone replacement therapy in post-menopausal women
how does alcohol cause cancer
