As the cells mature they rise to the surface and flatten out, so that on the surface the cells are flat. In dysplasia there is a lack of this organized growth process. In mild dysplasia only a few cells are abnormal, while in moderate dysplasia the abnormal cells involve about one half of the thickness of the epithelial surface. In invasive cancer the cells are not only disordered throughout the entire thickness of the lining, but they invade the stromal tissue underlying the surface as well. In this location the abnormal cells can spread to other parts of the body either directly or through blood or lymphatic channels.
Invasive cancer is treated entirely differently than dysplasia.
Important terms Please note that at the Sunnybrook Colposcopy Unit, the CIN and Bethesda classifications of cervical abnormalities are also used. CIN stands for cervical intraepithelial neoplasia. There are a number of epidemiological factors associated with dysplasia. Women who develop dysplasia do not necessarily have all or any of these factors. The virus may also be capable of transforming cells on the cervix so that they are more likely to turn into dysplasia.