Oral Cancer: Epidemiology, Molecular Pathogenesis, Early Detection Strategies, and Targeted Therapies

This chapter provides a comprehensive review of the global epidemiology and shifting risk factor profile of oral squamous cell carcinoma, with particular attention to the rising incidence of human papillomavirus-associated oropharyngeal cancer and the persistent burden of tobacco- and alcohol-related disease in low- and middle-income countries. It examines the molecular mechanisms underlying oral carcinogenesis — including oncogene activation, tumour suppressor gene silencing, epigenetic modifications, and immune evasion — and evaluates advances in biomarker discovery for early detection in saliva, tissue, and liquid biopsy. Emerging therapeutic strategies, including checkpoint inhibitor immunotherapy, targeted molecular therapies, and the promise of personalised oncology in the management of advanced oral cancer, are critically reviewed.