What is CIN?
CIN is caused by the persistent infection of high-risk HPV subtypes. It is not a cancer but a 'preinvasive' disease, in which a group of malignant cells (called a lesion) has formed but has not yet invaded surrounding tissues and other parts of the body. In the name 'Cervical Intraepithelial Neoplasia', 'neoplasia' indicates an abnormal growth, and 'intraepithelial' indicates the position of the growth in between layers of cell tissue.CIN is usually categorized into grades which signify the proportion of abnormal to normal cells and correlates to the risk of progression to invasive cancer. Grade 1 signifies a low risk of cancer: most low grade CINs resolve themselves within a relatively short space of time. However, grades 2 and 3 imply a greater proportion of abnormal cells and a higher probability of eventual cancer.