T-cells are critical white blood cells that act like a police force in the body, fighting off infections, foreign invaders, and cancer. Tumor-infiltrating lymphocytes (TILs) are a group of white blood cells that work like special forces. They’ve broken off from the bloodstream and entered a cancerous tumor. In many patients, the TIL unit is understaffed and overworked.
One avenue cancer researchers are exploring is the use of TIL therapy. In simple terms, it’s finding ways to replicate what’s already working to boost the number of TIL cells in the body. This looks like taking a sample of a tumor and extracting the TIL cells from it, growing more like it, and injecting them back into the body (with many other steps in-between). This is personalized immunotherapy using the body’s own immune cells.
The presence of TIL in a tumor can signal that the immune system is involved in fighting the cancer. A “cold” tumor doesn’t have a lot of immune cells, a “hot” tumor does. “Hot” tumors are more likely to respond to immunotherapy.
TIL therapies for several GI cancers are currently in clinical trials. Some are studying how to design TIL therapy around specific mutations (called neoantigens), and other approaches are looking at how to enhance fatigued TIL cells.
Your treatment plan will be unique and dependent on several factors. Ask your doctor how your biomarker test results are informing your treatment plan and if you qualify for any clinical trials.
