Dysplasia is dysfunctional cell growth involving abnormal morphological changes, there are four ways cells can become dysplastic.
Dysplasia Definition Pathology
This is normal non dysplastic stratified squamous epithelium, the nuclei are all evenly spaced and mature and flattened off as they ascend to the surface of the epithelium.
This is an area of the same epithelium but here you can see that the cells are not flattening off and they're not maturing this is dysplastic and impact it's severely dysplastic.
Dysplasia is an alteration in the size shape and organization of cells and there is a continuum from mild to severe or low grade to high grade dysplasia. and the really important thing about dysplasia is that it is pre malignant.
Dysplasia may develop in the mucosa of patients with long-standing host of colitis and displays it was always seen in adenomatous polyps.
Dysplasia is pre malignant the low-grade changes however may regress but high-grade or severe dysplasia has a significant chance of eventually developing into carcinoma.
Dysplasia has an alternative definition and this is an abnormal development of an organ or tissue this is completely different to the type of dysplasia that Tooker's in epithelium and importantly it is not pre malignant.
In this context dysplasia is a congenital condition and examples include fibrous dysplasia of the bone renal dysplasia, angiodysplasia in the right column and a potentially fatal condition in the heart called arithmetic right ventricular dysplasia.
The Progression of Cancer - Dysplasia
Firstly cells can grow large in size this is called hypertrophy or they can grow large and number this is called hyperplasia.
Cells can also shrink or decrease in number we refer to this as atrophy and finally cells can also change type we refer to this as metaplasia.
These changes occur due to some of normal stimuli to the cells. these stimuli could be non carcinogenic such as chronic irritation from smoke.
The stimuli could be carcinogenic which could cause genetic damage to the cells.
Dysplasia is often part of a pre malignant process we will use stratified squamous cells as an example.
Stratified squamous cells exist as such and are bound to a basement membrane with an abnormal stimulus such as a genetic abnormality cells lose general regulation over growth.
Proliferation they begin as low grade dysplasia which means the cell are not too different from the original selves.
However without removal of the stimulus in this case genetic damage the dysplasia only gets worse.
it then changes to medium grade and finally high grade dysplasia for the cells are very different from their original selves.
High-grade dysplasia is also termed less differentiated because they lose their original tissue specificity and the mutations cause them to form odd cell types which have no differentiation in the body.
Finally once the dysplasia takes the entire height of the epithelium up to the basement membrane it is referred to as carcinoma insights you.
Essentially this means that the cells are high-grade and ready to be invasive like a cancer but they have not yet penetrated the basement membrane.
Most carcinoma sites use do penetrate the basement membrane and then begin invading other regions.
once they break past the basement membrane they are referred to as invasive carcinomas or basically cancer.