Epithelial dysplasia
[2] Examples of epithelial dysplasia include cervical intraepithelial neoplasia – a disorder commonly detected by an abnormal pap smear) consisting of an increased population of immature (basal-like) cells which are restricted to the mucosal surface, and have not invaded through the basement membrane to the deeper soft tissues.
The principle behind these tests is that physicians expect dysplasia to occur at the same rate in a typical individual as it would in many other people.
Because of this, researchers design screening recommendations which assume that if a physician can find no dysplasia at certain time, then doing testing before waiting until new dysplasia could potentially develop would be a waste of medical resources for the patient and the healthcare provider because the chances of detecting anything is extremely low.
Epithelial dysplasia becomes microinvasive squamous cell carcinoma once the tumor begins to invade nearby tissue.
These terms are related since they represent three stages in the progression of many malignant tumors of the epithelium.
A. Normal histology, negative for anal intraepithelial neoplasia lesion (AIN)
B. Low-grade dysplasia, here called low-grade squamous intraepithelial lesion (LSIL)
C. High-grade dysplasia, here called high grade squamous intraepithelial lesion (HSIL)
D. Squamous cell carcinoma , infiltrating the stroma (middle and left in image), and HSIL (right in image)
