Systemic Therapy (definition of)

In oncology, systemic therapy is a form of treatment that involves the use of substances that are injected into the bloodstream or given orally in a form that can readily enter the bloodstream. It thus affects all cells in the body.

For comparison, local therapy is target at the site of the tumor. Most chemo and radiation treatment is of this type.

When systemic therapy is given in order to shrink a tumor in advance of surgery and/or chemotherapy and radiation, it is described as neoadjuvant.

Systemic therapy as used in the treatment of cancer, like mesothelioma, is not to be confused with the psychoanalytic technique of the same name.