Neoplasia Flashcards
Cancer is what type of disorder and caused by what
it is a genetic disorder caused by DNA mutations
what are the hallmarks of cancer
accumulation of mutations
the characteristics of cancer are:
- self sufficiency in growth signals
- insensitivity to growth inhibitory signals
- absence of apoptosis
- limitless proliferative capacity
- sustained angiogenesis
- tissue innovation and metastasis
- reprogramming of metabolic pathways
- ability to evade immune system
definition of neoplasia and neoplasm
- new growth
- tumour/cancer
cancer causes cells to undergo what
uncontrolled proliferation
benign is defined as
cells grow as compact mass and remain at their site of origin
malignant is defined as
growth of cells is uncontrolled and can spread to surrounding tissue
all tumors have two basic components:
parenchyma: neoplastic cells (determine behavior)
stroma: supporting host derived connective tissue, blood vessels, and inflammatory cells (help in growth)
characteristics of benign tumors
- expansive compressing tiusse
- do not recur
- do not metastasized
- grow slowly
- don’t cause cachexia
sarcomas are defined as
malignant neoplasms arising in mesenchymal tissue or its derivatives
leukemias or lymphomas are
malignant tumors arising from mesenchymal cells of blood
characteristics of malignant tumors
- invasive replacing tissue
- can recur
- may metastasize
- grow quickly
- can cause cachexia
mixed tumors are
when tumor cells undergo divergent differentiation
teratoma are
mixed tumor that originate from totipotential germ cells
the fundamental features by which benign and malignant tumors can be distinguished
- differentiation and anaplasia
- rate of growth
- local invasion
- metastasis
lack of differentiation is called
anaplasia
dysplasia is known as
disordered but non-neoplastic proliferation (vary in size and shape)
differentiation refers to
extent that neoplastic cells resemble normal cells
rate of growth depends on
doubling time of tumor cells, number of cells remaining in preoperative pool and rate that cells die
benign neoplasm often develop
fibrous capsule
cancer grow by
- progressive infiltration
- invasion
- destruction
- penetration of surrounding tissue
how are metastatic cancers spread
- direct seeding of body cavities
- lymphatic spread
- hematogenous spread (liver/lungs)
what affect does acquired preneoplastic lesion have on
increase likelihood of malignancy
what are the four classes of normal regulatory genes that are principal targets of genetic damage
- growth promoting proto oncogene
- growth inhibiting tumor suppressor genes
- genes that regulate apoptosis
- genes involved in DNA repair
proto oncogenes are
normal genes that regulate growth, cell division, and ability to adhere to other cells
tumor suppressor genes are genes that
prevent uncontrolled cell division
a mutation to tumor suppressor genes leads to
predisposition of cancer
a mutation to proto oncogenes may lead to
cause it to become an oncogene
types of genetic lesion in cancer are
- point mutation
- insertion/deletion/translocation
- chromosome changes
- amplification
- gene silencing
- exogenous sequences
what are epigenetic modifications
- DNA methylation
- histone tail modification
what are the hallmarks of cancer
1&2: proliferated cell growth
3: cells don’t die easily
4: cells divide forever
5: cells get more blood supply
6: cells escape and spread
why do cells get more blood supply in cancer
fast growing cells need more nutrients and get rid of more waste
due to a larger amount of cells seen in cancer, what do cancer cells induce
angiogenesis by signaling VEGF
in tissue invasion and metastasis what occurs
primary tumor spawn pioneer cells that move out founding new colonies
what are the steps for invasion-metastasis cascade
- local invasion
- intravasation into blood lymph vessels
- transit through vasculature
- extravasation
- formation of micrometastases
- growth of micrometastases
what the classes of carcinogenic agents
- chemicals
- radiant energy
- microbial agents
