An Explainable Privacy Preserving Multimodal Ensemble Framework For Skin Lesion Classification

Among dermatological diseases, skin cancer is among the most life-threatening. Early and accurate diagnosis is important for improving a patient's prognosis. Nevertheless, traditional AI-based diagnostic methods face several challenges, including privacy concerns, limited interpretability, and a severe class imbalance in multi-class skin lesion datasets. To overcome these challenges, the proposed paper proposes a privacy-aware, explainable multimodal skin lesion classification model that combines complex deep learning models and an ensemble modeling approach with explainable artificial intelligence methods. Experimental evaluation is conducted using publicly available HAM10000 benchmark data on multi-class skin lesion classification that can be accessed by means of Kaggle Hub, distributed over seven clinically significant lesion classes (akiec, bcc, bkl, df, mel, nv, vasc). To balance the data, a class-balancing technique is used to boost the minority classes. The EfficientNet B4, DenseNet201, and MobileNetv2 are used to extract deep feature representations, afterward combined with salient clinical metadata to create a robust multimodal feature space. These multimodal features are used to train XGBoost, LightGBM, Deep Neural Classifier (DNC) that resulted classification accuracies of 92%, 90% with 94% respectively. A stacked ensemble strategy is applied to combine the outputs of XGBoost, LightGBM, and Deep Neural Classifier (DNC), which leads to an improvement in accuracy of 96%. Model interpretability techniques provide feature-level explanations that increase transparency. The experimental findings proved the practicality of the suggested framework in terms of efficiency with clinically relevant real-life classification of skin lesions.