Immunooncology

Immuno-oncology is a field that studies interactions between the immune system and cancer, and develops therapies that harness or modulate immune responses to treat tumors. It emerged from observations that the immune system can recognize and sometimes control cancer, and from the success of cytokines and later checkpoint inhibitors.

The main approaches include immune checkpoint blockade (antibodies against CTLA-4, PD-1, PD-L1), adoptive cell therapy such as CAR-T cells and T cell receptor-engineered cells, therapeutic cancer vaccines, oncolytic viruses, cytokines like IL-2 or interferons, and bispecific T cell engagers that redirect T cells to tumor cells. These strategies aim to overcome tumor-induced immunosuppression and to promote durable anti-tumor responses.

Clinically, several checkpoint inhibitors have become standard of care for multiple cancers, including melanoma, non-small cell lung cancer, renal cell carcinoma, and others. CAR-T cell therapies are approved for certain B cell malignancies. The effectiveness varies with tumor type and individual factors. Tumor microenvironment characteristics influence response; biomarkers such as PD-L1 expression, tumor mutational burden, and microsatellite instability are used to guide treatment.

Challenges include primary and acquired resistance, immune-related adverse events affecting various organs, and high treatment costs. Research continues into combination therapies, novel targets, personalized vaccines, and better biomarkers to expand benefit and minimize toxicity.