Immune clusters in tumors follow a universal pattern
Organised clusters of immune cells inside tumours follow the same structural pattern across dozens of cancer types. That is the headline finding of a large-scale spatial atlas of tumour immunity.
Some tumours contain organised groupings of immune cells that resemble lymph nodes found elsewhere in the body. These are called tertiary lymphoid structures, or TLS. They have previously been linked to better treatment outcomes in certain cancers, but whether that applies broadly was unclear.
The researchers mapped these structures in a pan-cancer analysis, comparing patterns across many cancer types simultaneously. They used spatial data that recorded the exact position of each cell in tumour tissue. The result is a reference atlas of TLS patterns spanning dozens of cancer types.
Structure predicts outcome
The presence and maturity of TLS correlated with how well patients responded to treatment, including immunotherapy. More mature structures, with clearly distinct B-cell and T-cell zones, were associated with better survival. That pattern held across multiple cancer types.
This is relevant to aging because the immune system becomes less effective at building and maintaining these structures over time. Older patients sometimes respond less well to immunotherapy, even when their tumour looks similar on paper to that of a younger patient.
A target for therapy
If TLS are a reliable predictor of treatment response, they may also become a therapeutic target. Treatments that promote the formation or maturation of these structures could enhance the effectiveness of existing immunotherapies. That is a direction now being actively explored.
The atlas itself serves as a reference. Researchers can now check whether a tumour contains TLS, how mature they are, and what that has historically meant for comparable patients. That improves the basis for personalised treatment decisions.