Known Benefits and Unknown Risks of Active Surveillance of Cervical Intraepithelial Neoplasia Grade 2

Cervical intraepithelial neoplasia grade 2 (CIN 2) is an equivocal diagnosis with high interobserver variation. Owing to high regression rates of 50%, many countries recommend active surveillance of CIN 2, especially in women younger than age 25–30 years, where regression rates are even higher (ie, 60%). Additionally, excisional treatment is associated with increased risk of reproductive harm, particularly preterm birth. Active surveillance typically consists of semi-annual follow-up visits for up to 2 years, including colposcopy and either cytology, testing for human papillomavirus, or both. Excisional treatment is recommended for progression or persistent disease after 2 years. Because active surveillance in younger women is relatively new, knowledge on subsequent risk of cervical cancer is limited. Considering human papillomavirus latency, women undergoing active surveillance might be at higher risk of cervical cancer than women undergoing excisional treatment. Furthermore, there are limited data describing preferences of women for the management of CIN 2, and it is also unclear how active surveillance may affect planning for future pregnancy. In this context, biomarkers for risk stratification of CIN 2 into either high or low probability of progression would allow for targeted treatment. Currently, immunohistochemical staining for p16 is used to clarify the histologic diagnosis, but whether it or other biomarkers can be used for risk-stratification in clinical management of women with CIN 2 remains unknown. In conclusion, active surveillance of CIN 2 needs further investigation, including understanding the long-term cervical cancer risk and evaluation of markers that may enable risk stratification of CIN 2.