Ocular Toxicities of Anticancer Therapies in the Era of Precision Oncology: A Practical, Clinically Oriented Narrative Review

The introduction of modern anticancer therapies, including targeted therapies (TTs), immune checkpoint inhibitors (ICIs), and antibody–drug conjugates (ADCs), has significantly improved survival across a wide range of malignancies. At the same time, these agents have expanded the spectrum of treatment-related adverse events, with ocular toxicities emerging as a clinically relevant and increasingly recognized complication. Ocular adverse events may affect multiple anatomical structures, including the ocular surface, cornea, anterior and posterior segments, and optic nerve, often reflecting drug class-specific biological mechanisms. The pathogenesis of ocular toxicity is multifactorial and includes on-target inhibition of signaling pathways expressed in ocular tissues, off-target effects on rapidly renewing epithelia, non-specific uptake of cytotoxic payloads in ADCs, immune-mediated inflammation associated with ICIs, and microvascular dysregulation observed with selected targeted agents, such as mitogen-activated protein kinase (MEK) inhibitors. Because ocular adverse events are inconsistently reported in clinical trials and frequently described through case reports or pharmacovigilance data, their true incidence is likely underestimated and management strategies remain heterogeneous. This narrative review provides an overview of the epidemiology, biological mechanisms, and clinical manifestations of ocular toxicities associated with contemporary anticancer therapies. In addition, it offers practical, mechanism-based recommendations for prevention, monitoring, and stepwise management, emphasizing the importance of multidisciplinary collaboration to preserve visual function while maintaining effective oncologic treatment.