Unique recurrence patterns of cervical intraepithelial neoplasia following excision of the squamo-columnar junction.

Recent studies have identified a putative cell of origin for cervical intraepithelial neoplasia (CIN) and cervical cancer at the squamo-columnar junction (SCJ) and suggest that these cells may not regenerate following excision (LEEP). This study addressed the impact of SCJ excision on the temporal dynamics, histologic and viral (HPV) characteristics of recurrent CIN. One hundred thirty one consecutive patients treated by excision and attending follow-up visits were enrolled. We compared recurrent and initial CIN with attention to excision margins, timing of recurrence, CIN grade, HPV types, p16 immunophenotype, and SCJ immunophenotype. During the follow-up period (up to four years), sixteen (12.2%) recurrences were identified. Four (25%) were identified at the first follow-up visit, closely resembled the initial CIN 2/3 in grade and HPV type, and were typically SCJ marker positive [SCJ(+)], suggesting non-excised (residual) disease. Twelve (75%) manifested after the first postoperative visit and all were in the ectocervix or in mature metaplastic epithelium. All of the 12 delayed recurrences were classified as CIN 1 and were SCJ (-). Nine of 11 SCJ (-) recurrences (82%) followed regressed spontaneously. Taken together, these results show that new lesions developing from any HPV infection are delayed and occur within the ectocervix or metaplastic epithelium. This dramatically lower risk of CIN 2/3 following successful SCJ excision suggests that removal of the SCJ could be a critical variable in reducing the risk of subsequent CIN 2/3 and cervical cancer. (c) 2014 Wiley Periodicals, Inc.