Neoadjuvant therapy is a type of treatment given to patients before their main treatment, such as surgery or radiation therapy. This approach is often used in cancer treatment to shrink a tumor before surgery in order to make it easier to remove, or to make the tumor more responsive to subsequent treatment. Neoadjuvant therapy can also help doctors assess how well a patient responds to treatment and adjust their plan accordingly. This type of therapy can be used in a variety of cancer types, including breast, lung, and esophageal cancer.