AIM: To assess the risk factors for positive margin and residual high-grade lesions after cold knife conization (CKC) in postmenopausal patients.

METHODS: This retrospective study included a total of 173 postmenopausal patients aged ≥50 years who underwent hysterectomy after CKC at Peking University Third Hospital between September 2012 and February 2023. Statistical analyses were carried out using SPSS 22.0 for Windows. Variables with p-values ≤ 0.05 on univariate analysis were included in multiple logistic regression analysis, which utilized the forward likelihood ratio method.

RESULTS: Among the 173 patients, 27.17% (47/173) patients exhibited positive endocervical margins after conization, including seven patients (14.89%) with cervical intraepithelial neoplasia (CIN)2, and 40 patients (85.11%) with CIN3. Independent predictors of positive endocervical margin (> CIN1) were identified, including abnormal ThinPrep cytologic test (TCT) type (> low-grade squamous intraepithelial lesion, LSIL) (odds ratio [OR] = 2.193, 95% CI: 1.058–4.546, p = 0.035). All patients received hysterectomy. Pathological findings of uterine specimens revealed residual CIN2 in 18 patients (10.40%), CIN3 in 18 patients (10.40%), and cervical cancer in 3 patients (1.73%). Endocervical curettage (ECC) results (> CIN1) (odds ratio (OR) = 2.663, 95% CI: 1.049–6.764; p = 0.039) along with endocervical margin status (OR = 6.510, 95% CI: 2.935–14.444; p < 0.001) were identified as significant independent predictors of residual lesions. A regular post-hysterectomy follow-up in 97 patients revealed vaginal intraepithelial neoplasia (VaIN) grade 2/3 in two individuals six months later.

CONCLUSIONS: CKC can serve as a primary diagnostic modality for high-grade intraepithelial lesions in postmenopausal patients. Although this study did not identify cone height as a risk factor for positive endocervical margins, it is still recommended to maintain sufficient cone height, given that atrophy and upward migration of the cervical transformation zone are common in postmenopausal patients. For menopausal patients with positive endocervical margin, glandular involvement, and abnormal ECC results (> CIN1), immediate treatment such as hysterectomy is recommended.