Both cryotherapy and thermal ablation are treatment methods for cervical precancerous lesions in screening programs in resource constrained settings. However, for thermal ablation the World Health Organization stated that there is insufficient data to define a standard treatment protocol. This study used an ex-vivo model to compare the tissue interaction of both cryotherapy and thermal ablation to contribute to a treatment protocol. We used porcine tissue to measure the temperature profile over time at 0, 2, 4 and 6 mm depth. For cryotherapy the standard double freeze method was used, thermal ablation was applied for one cycle of 60 s with 100 °C. Based on literature search we used 4 mm depth as landmark for the depth of precancerous lesions, and -10 °C for cryotherapy and 46 °C for thermal ablation as critical temperature to induce cell necrosis. Cryotherapy achieved the critical temperature for tissue necrosis (-10 °C) in 3 out of 6 experiments at 4 mm depth, median minimum temperature was −9.6 °C (IQR 25–75 -15.8 °C to −4.9 °C). Thermal ablation achieved the critical temperature for tissue necrosis (46 °C) in 3 out of 7 experiments at 4 mm depth, median maximum temperature was 43.1 °C (IQR 25–75 42.3 °C to 49.9 °C). Both treatment modalities achieved tissue necrosis at 4 mm depth in our ex-vivo model. For cryotherapy the double freeze technique should be used. For thermal ablation a single application less than 60 s might not be sufficient and multiple applications should be considered.

Background: Thermal coagulation is gaining popularity for treating cervical intraepithelial neoplasia (CIN) in screening programs in low- and middle-income countries (LMICs) due to unavailability of cryotherapy. Objectives: Assess the effectiveness of thermal coagulation for treatment of CIN lesions compared with cryotherapy, with a focus on LMICs. Search strategy: Papers were identified from previous reviews and electronic literature search in February 2018 with publication date after 2010. Selection criteria: Publications with original data evaluating cryotherapy or thermal coagulation with proportion of cure as outcome, assessed by colposcopy, biopsy, cytology, and/or visual inspection with acetic acid (VIA), and minimum 6 months follow-up. Data collection and analysis: Pooled proportions of cure are presented stratified per treatment modality, type of lesion, and region. Main results: Pooled cure proportions for cryotherapy and thermal coagulation, respectively, were 93.8% (95% CI, 88.5–97.7) and 91.4% (95% CI, 84.9–96.4) for CIN 1; 82.6% (95% CI, 77.4–87.3) and 91.6% (95% CI, 88.2–94.5) for CIN 2–3; and 92.8% (95% CI, 85.6–97.7) and 90.1% (95% CI, 87.0–92.8) for VIA-positive lesions. For thermal coagulation of CIN 2–3 lesions in LMICs 82.4% (95% CI, 75.4–88.6). Conclusions: Both cryotherapy and thermal coagulation are effective treatment modalities for CIN lesions in LMICs.