The aim of the study was to evaluate recurrence risk of cervical intraepithelial neoplasia (CIN) 3+ and adenocarcinoma in situ (AIS)+ in a large population cohort of women previously treated for CIN 3/AIS.
Merging administrative databases with information on health services utilization and jurisdictional cancer registry, we identified all women undergoing treatment for CIN 3 or AIS from 2006 to 2010. Recurrence rate 1–5 years after treatment was defined as a biopsy finding of CIN 3/AIS or retreatment (loop electrosurgical excision procedure [LEEP], laser, cone, hysterectomy). Logistic regression was used to determine odds of recurrence.
A total of 15,177 women underwent treatment for CIN 3 (n = 14,668) and AIS (n = 509). The recurrence rate for 5 years was greater for AIS (9.0%) compared with CIN 3 (6.1%). In a multivariate analysis, increased risk of recurrence was shown for age older than 45 years (hazard ratio (HR) = 1.3, 95% CI = 1.1–1.6), AIS compared with CIN 3 (HR = 2.2, 95% CI = 1.5–3.5) first cytology after treatment showing high grade (HR = 12.4, 95% CI = 9.7–15.7), and no normal Pap smears after treatment (HR = 2.8, 95% CI = 2.2–3.7). There was no difference in recurrence risk with treatment type (cone vs LEEP: HR = 1.0, 95% CI = 0.8–1.2, and laser vs LEEP: HR = 1.1, 95% CI = 0.8–1.4) or number of procedures per year performed by physicians (<40 vs >40 procedures: HR = 1.1, 95% CI = 0.9–1.3).
Recurrence risk of CIN 3 and AIS is related to age, histology, and posttreatment cytology, which should assist with discharge planning from colposcopy. Definitive treatment with hysterectomy should be considered in women older than 45 years with additional risk factors for recurrence.