Value of top-hat procedure in management of squamous intraepithelial lesion

Aim: To investigate the features of skip lesions and evaluate value of top-hat procedure in management of squamous intraepithelial lesion.

Methods: We reviewed the records of patients who underwent loop electrosurgical excision procedure (LEEP) in Peking University First Hospital between 2011 and 2016. Patients were confirmed to have CIN1-3. The term 'skip lesion' refers to lesion lying deep in cervical canal discontiguous with other lesions in transformation zone and was confirmed by top-hat. We compared their lesion grade in patients with or without skip lesion using logistic regression. We further reviewed patients who underwent subsequent hysterectomy within 6 months following LEEP and evaluated if top-hat procedure led to less residual lesions or was able to predict residual lesions.

Results: A total of 2260 patients were included and 595 underwent top-hat procedure. Thirty-nine out of 595 patients had skip lesions (6.5%), among whom two patients had CIN1 (5.1%), eight had CIN2 (20.5%) and 29 had CIN3 (74.4%). Logistical regression showed CIN3 was associated with higher risk of skip lesions compared to CIN1 (OR = 4.433, 95%CI: 1.036-18.964), while CIN2 was not (OR = 1.762, 95%CI: 0.366-8.471). Sixty-two patients underwent hysterectomy within 6 months following LEEP (CIN1-3), 24 underwent top-hat. Analysis revealed top-hat procedure did not result in less residual lesions. Colposcopy impression or prior HPV test was unable to predict skip lesions.

Conclusion: About 9.4% patients with CIN3 had skip lesions in the study, which is associated with elevated risk for residual lesion. Top-hat procedure is able to detect skip lesions, but should not be performed on routinely because its prognostic value is not proved.