Cancer remains a significant global health challenge, with increasing incidence and mortality rates projected for the coming years. Early detection plays a crucial role in improving survival rates, highlighting the importance of innovative approaches in cancer diagnosis and treatment. This book chapter explores recent advancements in nanomedicine, focusing on the utilization of smart nanoparticles and biosensors for early cancer detection and targeted therapy. Smart nanoparticles offer unique advantages, including precise drug delivery and controlled release mechanisms triggered by endogenous or exogenous stimuli. Biosensors, with their ability to detect specific biomolecules indicative of cancer, provide additional tools for accurate and timely diagnosis. Early detection strategies involving imaging techniques, biomarkers, and biosensors are discussed, alongside the promising role of nanoparticle-based therapies in improving outcomes for patients. These advancements represent a paradigm shift in cancer management, offering enhanced precision, efficiency, and therapeutic outcomes in the fight against this formidable disease.