Over the recent years, immunomodulators have opened a new avenue in cancer treatment by virtue of their ability to boost the immune system for neoplastic cell elimination. Improving treatment outcomes by leveraging the interaction of these agents with traditional cancer treatments is the main emphasis of this review. Checkpoint inhibitors, chemokine receptors, and pattern recognition receptors are the immunological targets of their interactive mechanisms. Immunomodulators are generally categorized as inhibitors of checkpoint, cytokines, agonists, or adjuvants. Despite their high efficacy and specificity, modern-day antibody-based therapies face several key limitations such as immunogenicity, insufficient tissue penetration, and restricted oral bioavailability. To address these shortcomings, researchers are crafting small molecules with the potential for oral administration and improved pharmacokinetic properties. These agents can augment antibody therapies for synergistic effects to enhance therapeutic efficacy for different types of cancers. This review explores the synergy between immunomodulators and traditional cancer treatments (chemotherapy, radiation, and targeted therapies) as well as newer strategies like adoptive cell therapies (chimeric antigen receptor therapies such as chimeric antigen receptor-T (CAR-T) cell therapy and chimeric antigen receptor-natural killer (CAR-NK)). These combinations improve treatment effectiveness in a number of ways: radiotherapy increases tumor antigen presentation and T-cell infiltration, chemotherapy-induced immunogenic cell death boosts immune responses and targeted therapies lessen immunosuppression in the tumor microenvironment. Despite the potential appeal as adjuvants, immunomodulators also pose challenges in maximizing their efficacy and minimizing adverse effects. In this paper, clinical trials proving the effectiveness of these combined techniques are reviewed, and innovative approaches including next-generation checkpoint inhibitors and delivery systems based on nanoparticles are also highlighted. Overall, this review evaluates the existing impact of immunomodulatory adjuvants and their prospective trends in cancer care. Further development of immunomodulators will pave the way for more accessible and effective therapies, marking a significant step towards personalized oncological interventions.