Is there any clinical advantage in separating CIN 2 from CIN 3 in the current two-tiered cytological classification?

Aim: To investigate the practical use of description for CIN 2 or CIN 3 in HSIL cytology, the objective of the present study is to compare the prevalence of histologic CIN 2/3 or cancer (CIN 2+) between women with cytologic CIN 2 and CIN 3.

Methods: The medical records of women with high-grade squamous intraepithelial lesion (HSIL) on cytology who underwent colposcopy at Rajavithi hospital between January 2001 and March 2005 were reviewed.

Results: Of 152 women with HSIL, 70 and 82 had cytologic change compatible with CIN 2 and CIN 3, respectively. Women from HSIL-CIN 3 were significantly more likely to have CIN 2/3 or cancer than those from HSIL-CIN 2. Histology-proved CIN 2+ was confirmed in 64.3% and 85.4% in HSIL-CIN 2 and HSIL-CIN 3, respectively (p<0.05). Invasive cancer was found in 5.7% in HSIL-CIN 2 and 9.8% HSIL-CIN 3.

Conclusion: The histologic outcome is obviously different between women with cytologic CIN 2 and CIN 3. However, both groups should be managed similarly because of the high prevalence of high-grade cervical lesion including invasive cancer.