Colorectal cancer remains one of the leading causes of cancer-related mortality worldwide. Accurate segmentation of polyps and tumors in colonoscopy images is critical for early detection and effective treatment planning. Traditional segmentation methods relied on hand-crafted features, while deep learning methods, particularly U-Net and its variants, have significantly advanced accuracy. More recently, Generative Adversarial Networks (GANs) have been employed for colon cancer segmentation and synthetic data generation, addressing challenges of limited annotated datasets. This survey summarizes key developments in colon cancer segmentation techniques, explores GAN-based advancements, compares state-of-the-art methods, and highlights challenges such as data scarcity, model instability, and generalization. Finally, future research directions are discussed, emphasizing optimization methods, transformer-GAN hybrids, and privacy-preserving learning.
Introduction
1. Overview
Colorectal cancer (CRC) is a leading global cause of cancer-related deaths.
Early detection is critical to improving survival, with medical imaging (colonoscopy, CT, MRI) playing a key role.
Accurate segmentation of cancerous regions is essential for diagnosis and treatment.
2. Challenges in CRC Image Segmentation
Traditional methods using handcrafted features (intensity, texture, shape) lack robustness across large and diverse datasets.
Tumor irregularities, low contrast, and imaging variations reduce segmentation accuracy.
Deep learning models, especially U-Net and its variants, have improved results but require large annotated datasets.
3. Advancements in Deep Learning and GANs
CNN-based U-Net revolutionized biomedical segmentation with encoder–decoder and skip connections.
Enhanced variants:
UNet++: Dense connections improve small tumor detection.
Attention U-Net: Uses attention mechanisms to focus on tumors.
PraNet: Designed for polyp segmentation using boundary refinement.
Employ semi- and self-supervised GANs to leverage unlabelled data.
Combine with Explainable AI (XAI) to increase clinical trust.
Conclusion
The Colon cancer remains a major health concern worldwide, where accurate segmentation of polyps and tumors plays a vital role in early detection and effective treatment. Advances in deep learning, particularly U-Net variants and Transformer-based models, have significantly improved segmentation performance. More recently, Generative Adversarial Networks (GANs) have shown remarkable potential in both boosting segmentation accuracy and generating realistic synthetic data to overcome dataset limitations. Optimization methods, such as the Sine Cosine Algorithm, further strengthen GAN stability and efficiency. Looking ahead, the integration of GANs with emerging deep learning paradigms offers promising pathways toward more reliable, generalizable, and clinically useful computer-aided diagnosis.
References
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