Vaccination in Oncology Patients: Evidence, Clinical Challenges, and Future Directions

This narrative review provides a comprehensive synthesis of patients with cancer disproportionately affected by vaccine-preventable infectious diseases due to malignancy-related immune dysfunction and treatment-induced immunosuppression. Vaccination represents a cornerstone of supportive care in oncology; however, vaccine uptake remains suboptimal and immune responses are frequently attenuated, particularly in patients with hematological malignancies and those receiving highly immunosuppressive therapies. This review provides a comprehensive synthesis of current evidence on vaccine immunogenicity, clinical effectiveness, and safety in oncology patients. We discuss immunological mechanisms underlying impaired vaccine responses, summarize evidence for major vaccines recommended in oncology practice, and address key clinical challenges such as timing relative to anticancer therapies, heterogeneity of immune responses, and vaccine hesitancy. An extended discussion highlights emerging strategies, including booster dosing, adjuvanted vaccines, and personalized vaccination approaches. Finally, future perspectives are outlined to improve integration of vaccination into routine oncology care.