Advancements in immune monitoring and modulation technologies are driving transformative changes in cancer immunotherapy. These innovations are crucial for assessing patient-specific immune responses, enabling more accurate predictions of therapeutic efficacy and enhancing treatment outcomes. This review provides a comprehensive overview of current technologies used in immune monitoring, such as flow cytometry, single-cell RNA sequencing, and multiplex cytokine profiling. It also explores cutting-edge immune modulation methods, such as biomaterials that activate immune cells and genetically engineered cell-based therapies. We examine the strengths and limitations of these techniques and identify areas where further progress is needed. In particular, we explore how personalized therapies, real-time monitoring systems, and artificial intelligence shape the future of immune-based treatments. Through a comparative analysis of existing platforms and emerging solutions, this paper underscores the importance of integrating diverse scientific approaches-from immunology and bioengineering to data science-in advancing safer, more effective cancer treatments. This interdisciplinary approach promises to enhance the precision and accessibility of immune-based therapies, offering new hope for improved cancer care.