neoplasia Flashcards
neoplasia (def)
persistent abnormal growth of tissue which exceeds and **uncoordinated w/ growth of surrounding normal tissues.
2 defining characteristics of neoplastic cells
- ability to replicate in absence of control by growth factors
- making a mass of new cells with no useful function
3 tumor characteristics like their parent organ
- all have parenchyma (functioning part of tissue) and stroma (supporting part of tissue)
- tumor cells look similar to cells in the organ where tumor arose
- tumor cells perform some of the functions of the parent organ
4 ways tumor characteristics are different from organs
- don’t contribute to body homeostasis
- grow more rapidly than surrounding tissue
- some benign and all malignant tumors never cease to grow (sign of malignancy)
- most tumors show some derangement of histologic architecture (this is dysplasia)
4 characteristics of benign tumors
- cells resemble normals cells and tumor architecture resembles that of the parent organ
- usually are spherical and compress the surrounding tissue
- grow slowly
- never metastasize (spread from primary location to another)
5 characteristics of malignant tumor
- grow more rapidly than benign
- differ morphologically and functionally from normal cells and tumor architecture is less organized than that of parent cell
- locally invasive and grow into surrounding tissue and destroy it
- tumor will metastasize, spreading to another site remote from original tumor (**not all malignant tumors metastasize **exceptions: basal cell skin carcinoma and brain glioma)
- cells resemblance to parent cells will be better or worse depending on whether tumor is “well differentiated” or “poorly differentiated” (more difference = more aggressive)
nomenclature of tumors
ends in “oma”
ends in “carcinoma”
ends in “sarcoma”
- ends in “oma”- usually benign (except melanoma)
- ends in “carcinoma”- epithelial - malignant- lymphatic
- ends in “sarcoma”- mesenchymal - malignant- BV
tumor grades and stages
why stages are assigned - what it’s based on
how grades are assigned- what it’s based on
- stages are assigned to give prognosis and determine treatment - based on how far it spread
- grades are assigned by the cancers degree of differentiation which correlates with how aggressive it is
tumor grades (5)
I- well differentiated (like normal) II - not so well differentated III - worse than grade II (anaplastic) IV - poor differentation (anaplastic) V - not differentiated (anaplastic)
what is anaplastic?
not recognizable/ no resembalance
tumor stages (3)
I - smaller than 1 cm diameter - no metastases
II - larger than 1 cm w/ metastases to regional lymph nodes
III - tumor has infiltrated a deep tissue structure w/ distant metastases
TNM grading system(malignant tumors)
T- tumor (T1-T3)
N- lymph nodes (N0-N2)
M- metastases (M0-M1)
T1: tumor is < 1cm T2: > 1cm T3: invading non-resectable structure N0: no tumor in regional lymph nodes N1: tumor in nearby lymph nodes N2: tumor is in further lymph nodes M0: no distant metastases M1: distant metastases
malignancy
microscopic appearance
histologic diagnosis (what mitoses looks like)
size of malignancy
- increased nuclear DNA, increased nuclear/ cytoplasmic ratio, wrinkled nuclear edges = chaotic and disorganized
- numerous bizarre mitoses that last longer than in healthy tissue
- widely varying sizes with loss of orientation to one another
miotic figure…
def
what it may indicate
when you see it normally
- def- microscopic appearance of a cell undergoing mitosis
- are more likely to be seen in malignant neoplasm.
- normally this number of mitoses can be seen in bone marrow, gonads and GI tract
malignant tumor invasion
local infiltration
“intraepithelial spread”- characteristic of early cancers in wh/ an epithelial surface is replaced by a layer (several cells deep) of malignant tumor which has not yet penetrated the basement membrane
