According to a small but groundbreaking study, taking antibiotics in the month before starting immunotherapy dramatically reduces a cancer patient’s chances of survival.

Scientists at Imperial College London believe antibiotics strip out helpful bacteria from the gut, weakening the immune system. This appears to make it less likely that immunotherapy drugs will boost the body’s cancer-fighting capability.

How does immunotherapy work against cancer?
Immunotherapy is a type of biological therapy that helps the body’s immune system fight a disease such as cancer. The body’s immune system is programmed to detect abnormal cells and prevent malignant growth. A sign that indicates an immune response against cancer cells is when tumor-infiltrating lymphocytes (TILs) are found in and around tumors.

However, cancer cells have the ability to avoid immune response and survive through the following mechanisms: