Practical Models for Predicting Vaginal Intraepithelial Neoplasia in High-Grade Squamous Intraepithelial Lesions Patients within Two years After Conization.

Purpose: This study aimed to identify reliable risk factors for the development of Vaginal intraepithelial neoplasia (VaIN) within two years after the conization for high-grade squamous intraepithelial lesions (HSIL). We developed a prediction model to predict the risk of VaIN based on preoperative and follow-up data.

Methods: We collected 5358 patients who underwent conization for HSIL, of whom 99 developed VaIN within two years after conization. We selected 495 patients as the control group by randomly pairing them 1:5, and were randomly divided into development and validation cohorts at a ratio 7:3. Random Forest (RF), Lasso, and Extreme Gradient Boosting (XGBoost) were employed to identify the most influential variables in the model development dataset. The optimal variables selected through this process were then used for model construction. Subsequently, four machine learning models were developed, and their performance was evaluated using metrics including sensitivity, specificity, accuracy, area under the curve (AUC), and the F1 score. To enhance interpretability, the prediction process was visualized using Shapley Additive Explanations (SHAP). Finally, the model was deployed as a web-based clinical decision support system for practical clinical applications.

Results: Five key clinical predictive variables were identified: age, transformation zone (TZ) type, presence of VaIN before conization, follow-up cytology after conization, and follow-up HPV after conization. The optimal model demonstrated strong predictive performance, achieving AUC of 0.910 (95% CI: 0.854-0.966) in the internal validation cohort and 0.905 (95% CI: 0.859-0.951) in the external validation cohort.

Conclusion: We established a practical and accurate prediction model deployed in the network application to predict the occurrence of VaIN within two years after conization in patients with HSIL. This tool can facilitate targeted clinical decision-making for clinicians.