Cervical intraepithelial neoplasia (CIN) is a premalignant condition of the uterine cervix . The ectocervix (surface of the cervix that is visualized on vaginal speculum examination) is covered in squamous epithelium, and the endocervix, including the cervical canal, is covered with glandular epithelium. CIN refers to squamous abnormalities. Glandular cervical neoplasia includes adenocarcinoma in situ and adenocarcinoma. (See "Cervical cytology: Evaluation of atypical and malignant glandular cells" and "Cervical adenocarcinoma in situ" and "Invasive cervical adenocarcinoma".)
Screening tests for cervical cancer include cervical cytology and testing for oncogenic subtypes of human papillomavirus (HPV) (table 1). Follow-up of abnormalities in screening tests with colposcopy and cervical biopsy may result in a diagnosis of CIN, glandular neoplasia, or cervical cancer .
CIN may be low grade or high grade. Women with low-grade CIN have a low potential for developing cervical malignancy, while those with high-grade lesions are at high risk of progression to malignancy. In managing women with CIN, the goal is to prevent possible progression to invasive cancer while avoiding overtreatment of lesions that are likely to regress.
Management of CIN is reviewed here. Related issues are discussed separately:
●Treatment of CIN (see "Cervical intraepithelial neoplasia: Treatment and follow-up")