cervical intraepithelial neoplasia (CIN)
Gynaecology
Also known as: zervikale intraepitheliale Neoplasie (CIN) · servikal intraepitelyal neoplazi (CIN)
What it is for
Cervical intraepithelial neoplasia (CIN) is the histological grading of precancerous changes of the cervical squamous epithelium caused by persistent infection with high-risk human papillomavirus (HPV); it is not cancer.
Classification
| Category | Description |
|---|---|
| CIN 1 | abnormal (dysplastic) cells in the lower third of the epithelium (mild dysplasia). |
| CIN 2 | abnormal cells in up to the lower two thirds (moderate dysplasia). |
| CIN 3 | abnormal cells in more than two thirds up to the full thickness (severe dysplasia, includes carcinoma in situ). |
| Two-tier terminology (LAST project, also used by the WHO) | low-grade squamous intraepithelial lesion (LSIL) = CIN 1; high-grade squamous intraepithelial lesion (HSIL) = CIN 2 and CIN 3. |
| p16 rule (LAST) | when the H&E morphology is CIN 2 (or the differential is a high-grade lesion versus a mimic), p16 immunostaining is used to adjudicate: strong, diffuse block-positive p16 supports HSIL; negative or non-block (patchy) staining favours LSIL (or a non-HPV-related change). The morphological grade may be added in brackets, e.g. HSIL (CIN 2). |
Source
The Lower Anogenital Squamous Terminology Standardization Project for HPV-associated lesions
Arch Pathol Lab Med 2012;136:1266–1297 (Darragh TM et al.)
PMID: 22742517
- Edition
- LAST project 2012 / WHO
- Checked on
Summary of the published classification in our own words. Not a substitute for the original publication.
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