Early cancer detection improves patient outcomes by catching disease at more treatable stages. Artificial intelligence (AI) is advancing as an invaluable tool in oncology with its ability to enhance the sensitivity and efficiency of screening and diagnostic methods. AI systems are now leading innovative strategies for finding cancer early, from interpreting medical images to mining health records and analyzing blood biomarkers. This article reviews recent advancements in imaging-based detection, risk prediction, and novel diagnostics like liquid biopsies while also addressing the challenges of data bias, regulation, and privacy.