A 30-year-old woman's cervical biopsy shows koilocytes and nuclear atypia confined to the basal and middle thirds, with normal surface maturation. The correct CIN grade and typical HPV association are:
- A CIN 1 — typically low-risk HPV (6/11) or transient high-risk infection ✓
- B CIN 3 — HPV 16/18
- C CIN 2 — HPV 31/33
- D CIN 1 — exclusively HPV 16
Correct answer: A. CIN 1 — typically low-risk HPV (6/11) or transient high-risk infection
Explanation
CIN 1 (mild dysplasia) shows nuclear atypia in the lower one-third, koilocytes (perinuclear halos from HPV cytopathic effect), and intact surface maturation. Most CIN 1 is associated with low-risk HPV types (6, 11) or transient high-risk infections that often regress spontaneously. CIN 2 involves two-thirds and CIN 3 shows full-thickness atypia; both are more strongly linked to persistent HPV 16/18 infection.
Reference: Robbins & Cotran Pathologic Basis of Disease, 10th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.