The tumor immune microenvironment is a crucial predictor of response to immunotherapy. Tumors infiltrated by activated T cells, a cancer immune phenotype referred to as “immune-inflamed,” are most likely to respond to immune checkpoint blockade. However, approximately one-third of cancer patients have tumors that spatially compartmentalize T cells to the periphery of the tumor, referred to as the “immune-excluded” phenotype, and these tumors have a poor response rate to immunotherapy. The research we will discuss today has the potential to impact the future of immunotherapy, offering novel approaches for improved treatments and outcomes.
This session will highlight the latest research defining the cellular and molecular mechanisms of immune exclusion. It will feature an active debate on whether the physical versus the functional barrier prevents immune cell infiltration into the tumors. It will also explore the relevant crosstalk between stromal cells, myeloid cells, and lymphocytes that contributes to the immune-excluded immunophenotype. Based on the identified immune cell crosstalk, novel approaches to overcome immune exclusion will be discussed. The session will combine the perspectives of clinicians, pathologists, and basic science researchers from academia and industry to take a multi-prong approach to overcoming the challenges of immune exclusion.