“My LEEP was negative, but my patient had high grade dysplasia. Did I miss it?” A common question among physicians. Even the most conservative, in-office excision is not easy—and the idea that  a procedure could be performed unnecessarily or perhaps leave residual dysplasia untreated is frustrating and upsetting. On the other hand, a confirmation of an original diagnosis through the identification of previously diagnosed HSIL/CIN 2/3 within a cervical LEEP provides an assuring sense of closure to both provider and patient.  

According to literature, negative LEEP following a biopsy diagnosis of HSIL (CIN 2+) occurs between 14-17% of the time1. Assuming an adequately excised transformation zone, this may be due to two reasons:

  • Complete removal of the lesion via biopsy
  • Destruction or regression of the dysplasia by post-biopsy inflammation

Negative LEEP and High-Grade Dysplasia Data

A recent article2 sought to confirm the actual frequency of a negative LEEP, and to examine the clinical significance. 378 patients who underwent a LEEP procedure were selected, 306 of which had a biopsy proven diagnosis of CIN 2+. The findings showed:

  • 76% of patients had residual HSIL/CIN 2+ on the LEEP
  • 24% patients showed CIN 1 or negative findings within the LEEP specimen

Recurrence of HSIL/CIN 2+, after LEEP was as follows:

  • 13% of patients with HSIL/CIN 2+ in the LEEP had recurrent disease
  • 10% of patients without HSIL/CIN 2+ in the LEEP had recurrent disease

Other studies3 show a similar pattern of recurrence, although with higher recurrence rates:

  • 27% recurrence in patients with residual in HSIL/CIN 2+ in the LEEP
  • 24% recurrence in the patient group without residual HSIL/CIN 2+ in the LEEP.

(Importantly, there is no statistical difference between these pairs of recurrence rates.)  

In short, based on these results, patients with residual HSIL/CIN 2+ and negative (no residual) LEEPs should be followed up similarly. Approximately 10-25% of LEEPs performed for a diagnosis of HSIL/CIN 2+ will show recurrence of a high-grade lesion during the subsequent follow up, regardless of the presence of dysplasia within the excision specimen (assuming adequate excision of the transformation zone). Follow up cervical cytology six months after the procedure (allowing inflammation to subside) with concurrent HPV testing may be considered. In this testing plan, a patient can be giving a more reassuring confirmation about their diagnosis over time and the appropriate treatment plan will be able to be better applied.  

At PathAdvantage, we treat your patients as our patients. Read more about the PathAdvantage difference.



  1. Negative cone biopsies: a reappraisal. Diakomanolis E, Haidopoulos D, Chatzipapas I, Rodolakis A, Stefanidis K, Markaki S. 2003, J Reprod Med, pp. 617-621.
  2. Negative Loop Electrosurgical Cone Biopsy Finding Following a Biopsy Diagnosis of High Grade Squamous Intraepithelial Lesion; Frequency and Clinical Significance. . Witt BL, Factor RE, Jarboe EA, Layfield LJ. 2012, Arch Pathol Lab Med, pp. 1259-1261.
  3. The clinical significance of a negative loop electrosurgical cone biopsy for high-grade dysplasia. Livasy CA, Moore DT, Van Le L. 2004, Obstet Gynecol, pp. 250-254.