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

## TL;DR

This review explores how cancer patients face higher risks from vaccine-preventable diseases and examines the challenges and future strategies for improving vaccination in oncology.

## Contribution

The paper provides a comprehensive synthesis of vaccine immunogenicity, effectiveness, and safety in oncology patients, highlighting emerging strategies to improve vaccination outcomes.

## Key findings

- Cancer patients, especially those with hematological malignancies, show attenuated immune responses to vaccines.
- Vaccine hesitancy and timing relative to cancer therapies are significant clinical challenges.
- Booster dosing and adjuvanted vaccines are emerging strategies to enhance vaccine effectiveness in oncology.

## Abstract

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.