Immune Checkpoint โ Releasing the Brakes on Immunity
Why this matters
CTLA-4 and PD-1/PD-L1 represent distinct checkpoint axes that suppress T-cell responses. Blocking these pathways can restore antitumor responses in certain cancers, but the effects are not uniform across all tumors or patients. While immune activation may lead to durable responses, it can also trigger immune-related adverse events affecting multiple organs. Biomarkers such as PD-L1, MSI-H/dMMR, and TMB should be interpreted within the context of their respective assays, cutoff values, and approved indications. Selection of therapeutic agents and management of adverse events remain within the domain of specialized clinical guidelines.
Interpretation boundary
This article explains the concept and the limits of the evidence. It does not provide diagnostic, testing, or treatment decisions for an individual patient.