International Journal of Scientific Research and Engineering Development

Cancer remains a major global health challenge due to its increasing incidence, mortality, and complex biology. Traditional chemotherapy has long served as the primary treatment, but its non-selective cytotoxicity often results in significant toxicity. Advances in molecular oncology have enabled the development of targeted therapies, hormonal treatments, and immunotherapies that selectively disrupt cancer-specific pathways, improve survival, and reduce adverse effects. Preclinical evaluation using in vitro models, 3D cultures, and animal studies supports drug discovery, although many agents fail to translate clinically due to tumor heterogeneity and microenvironmental barriers. Drug delivery challenges including poor bioavailability and off-target effects limit therapeutic outcomes, prompting the development of nanocarriers and stimuli-responsive systems. Natural products continue to provide promising anticancer leads. Despite progress, resistance, toxicity, and limited specificity remain obstacles. Future success depends on precision medicine, biomarker-guided treatment, combination strategies, and advanced delivery platforms to achieve safer and more effective cancer therapy.