Colorectal disease diagnosis with deep triple-stream fusion and attention refinement.

Colorectal cancer constitutes a significant proportion of global cancer-related mortality, underscoring the imperative for robust and early-stage diagnostic methodologies. In this study, we propose a novel end-to-end deep learning framework that integrates multiple advanced mechanisms to enhance the classification of colorectal disease from histopathologic and endoscopic images. Our model, named TripleFusionNet, leverages a unique triple-stream architecture by combining the strengths of EfficientNetB3, ResNet50, and DenseNet121, enabling the extraction of rich, multi-level feature representations from input images. To augment discriminative feature modeling, a Multi-Scale Attention Module is integrated, which concurrently performs spatial and channel-wise recalibration, thereby enabling the network to emphasize diagnostically salient regions. Additionally, we incorporate a Squeeze-Excite Refinement Block (SERB) to selectively enhance informative channel activations while attenuating noise and redundant signals. Feature representations from the individual backbones are adaptively fused through a Progressive Gated Fusion mechanism that dynamically learns context-aware weighting for optimal feature integration and redundancy mitigation. We validate our approach on two colorectal benchmarks: CRCCD_V1 (14 classes) and LC25000 (binary). On CRCCD_V1, the best performance is obtained by a conventional classifier trained on our 256-D TripleFusionNet embeddings-SVM (RBF) reaches 96.63% test accuracy with macro F1 96.62%, with the Stacking Ensemble close behind. With five-fold cross-validation, it yields comparable out-of-fold means (0.964 with small standard deviations), confirming stability across partitions. End-to-end image-based baselines, including TripleFusionNet, are competitive but are slightly surpassed by embedding-based classifiers, highlighting the utility of the learned representation. On LC25000, our method attains 100% accuracy. Beyond accuracy, the approach maintains strong precision, recall, F1, and ROC-AUC, and the fused embeddings transfer effectively to multiple conventional learners (e.g., Random Forest, XGBoost). These results confirm the potential of the model for real-world deployment in computer-aided diagnosis workflows, particularly within resource-constrained clinical settings.