Development and Internal Validation of a Clinical Response-Estimation Model Incorporating Treatment-Course Exposure
Shufen Wang1, Gaoyuan Peng1, Wenyu Li2
1Department of Dermatology and Venereology, The First Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi, China..
Photodiagnosis and Photodynamic Therapy
|August 3, 2026
Summary
A new model predicts port-wine stain (PWS) essential cure after photodynamic therapy (PDT). Younger age, smaller lesions, facial location, pink type, and more sessions improve outcomes for PWS patients.
Area of Science:
- Dermatology
- Medical Imaging
- Biomedical Engineering
Background:
- Port-wine stain (PWS) treatment response to hematoporphyrin monomethyl ether photodynamic therapy (HMME-PDT) is variable.
- Patient characteristics and lesion properties influence HMME-PDT outcomes in PWS.
Purpose of the Study:
- Develop a predictive model for essential cure in PWS patients undergoing HMME-PDT.
- Assess the likelihood of achieving ≥90% lesion clearance post-HMME-PDT.
Main Methods:
- Retrospective study of 855 PWS patients treated with HMME-PDT.
- Multivariable logistic regression model incorporating age, lesion area, site, type, and treatment sessions.
- Internal validation using fixed stratified five-fold cross-validation.
Main Results:
- Essential cure achieved in 29.6% of patients.
- Younger age, smaller lesion area, face/neck location, pink lesion type, and ≥3 sessions correlated with higher cure rates.
- The five-factor model demonstrated good discrimination (AUC=0.850) and calibration.
Conclusions:
- A five-factor model accurately predicts essential cure likelihood after HMME-PDT for PWS.
- The model aids in treatment assessment and patient communication.
- External validation is recommended prior to clinical implementation.
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