Cold knife versus carbon dioxide for the treatment of preinvasive cervical lesion

Background and Objectives: Cervical cancer (CC) represents a significant health concern worldwide, particularly for younger women. Cold knife (CK) conization and carbon dioxide (CO2) laser conization are two techniques commonly used to remove pre-invasive lesions, offering a potential curative intent in cases of incidental diagnosis of CC. This study aimed to assess the clinical implications and pathological outcomes of CK vs. CO2 laser conization for pre-invasive lesions. Materials and Methods: We retrospectively analyzed women who underwent CO2 or CK conization for high-grade preinvasive lesions (CIN2/3, CIS and AIS) between 2010 and 2022. Patient demographics, surgical details and pathological outcomes were collected. Pregnancy outcomes, including composite adverse obstetric rates, and oncological follow-up data, were also obtained. Results: In all, 1270 women were included; of them, 1225 (96.5%) underwent CO2, and 45 (3.5%) underwent CK conization. Overall, the rate of positive endocervical or deep margins was lower with CO2 laser compared to CK (4.3% vs. 13.3%, p = 0.015). Incidental CC was diagnosed in 56 (4.4%) patients, with 35 (62.5%) squamous and 21 (46.6%) adenocarcinomas. In a multivariate regression model, the relative risk for positive endocervical or deep margins is significantly greater in cases of incidental diagnosis of CC (p < 0.01). In cases of incidental diagnosis of CC, we found that the probabilities of having either positive endocervical or deep margins after CO2 laser or CK conization are similar, with a higher risk in case of adenocarcinoma lesion. Among women with CC, 42 (75%) opted for radical treatment, while 14 (25%) underwent a follow-up. Only one woman (7.1%) in the follow-up group, who had undergone CK conization, experienced a composite adverse obstetric outcome. No recurrences were observed after a median follow-up of 53 months. Conclusions: CO2 laser conization achieved a lower positive margin rate overall. CK and CO2 conization appear to be equivalent oncological options for incidental CC.