A 35-year-old woman has a cervical biopsy showing dysplastic cells confined to the lower two-thirds of the epithelium without surface maturation. HPV genotyping shows high-risk HPV 16. This is best classified as:
- A CIN 1 (low-grade squamous intraepithelial lesion, LSIL)
- B CIN 2 (high-grade squamous intraepithelial lesion, HSIL) ✓
- C CIN 3 / carcinoma in situ
- D Reactive atypia
Correct answer: B. CIN 2 (high-grade squamous intraepithelial lesion, HSIL)
Explanation
CIN 2 is characterized by dysplastic changes extending through the lower two-thirds of the cervical epithelium, with surface maturation still present in the upper third. CIN 1 (LSIL) shows dysplasia limited to the lower third with koilocytosis. CIN 3 / carcinoma in situ involves full-thickness dysplasia without surface maturation. HPV 16 is the highest-risk oncogenic type most associated with progression to CIN 2-3 and invasive squamous cell carcinoma, acting through E6-mediated p53 degradation and E7-mediated pRb inactivation.
Reference: Robbins & Cotran Pathologic Basis of Disease, 10th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.