Overtreatment rate after immediate local excision of suspected cervical intraepithelial neoplasia: A prospective cohort study.

Objective: The gold standard of cervical intraepithelial neoplasia (CIN) treatment is large loop excision of the transformation zone (LLETZ) after histopathological diagnosis from punch biopsies. In addition, treatment may be appropriate at initial colposcopy. Our objective was to study the applicability of immediate treatment strategy according to clinical parameters.

Methods: We conducted a prospective cohort study among patients referred to colposcopy at Helsinki University Hospital, Finland, between January 2014, and September 2018 (ISRCTN10933736). Patients treated with LLETZ, either after biopsies or immediately at initial colposcopy, were included. The main outcome measure was overtreatment (OT) rate defined as normal or low-grade histopathological findings in LLETZ specimen within both treatment groups.

Results: A total of 572 patients treated with LLETZ were included: 360 treated after biopsies and 212 treated immediately at initial colposcopy. When LLETZ was performed immediately after high-grade referral cytology and with colposcopic impression of high-grade disease, the overtreatment (OT) rate was 10.0% (95% CI 9.10 to 17.2), whereas when LLETZ was done after biopsy-confirmed high-grade lesions, the OT rate was 18.9% (95% CI 14.7 to 23.7), resulting in risk difference (RD) -8.91% (95% CI -16.0 to -1.82). Among HPV16/18 positive patients the OT rate was 8.22% (95% CI 3.08 to 17.0) for immediate treatment, resulting in RD of -10.7% (95% CI -18.3 to -3.04) compared to LLETZ after biopsies.

Conclusions: Immediate LLETZ does not result in overtreatment when applied on selected cases, especially after high-grade referral cytology and when high-grade lesion is also colposcopically suspected.