The term invasive in Medicine has two meanings:

• A medical procedure which penetrates or breaks the skin or a body cavity, i.e., it requires a perfuration, an incision, a catheterization, etc. into the body
• An abnormal tissue growth, such as a neoplasm or tumor, that spreads (invades) to the surrounding healthy tissue (usually a malignant one).

Surgery is a typical medical invasive procedure. However, when there is minimal damage of biological tissues at the point of entrance of instrument(s), the procedure is called minimally invasive. There are also many non-invasive procedures, including surgery (e.g., radiosurgery).