Systemic Treatment

In medicine systemic treatment refers to drugs or therapies that potentially affect the entire body.  Local treatment addresses the disease or injury at a specific point.  Cancer can be treated both ways.

Local (or regional) treatment is done where the doctor knows or strongly suspects the presence of cancer.  It is ideally done early in the cancer’s progression, before metastasis.  Surgery and radiation are local treatments, as are the less used topical therapy and cryotherapy.

Systemic treatment is sometimes also done before surgery.  Neo-adjuvant chemotherapy fits this description and sometimes immunotherapy does, too.

Cancer is potentially a systemic disease – just like the flu.  Many cancers stay local.  Either the body’s immune system or medical intervention prevents them from spreading broadly.  Experts estimate 50% of discovered (diagnosed) cancers spread so far they are considered metastatic.  Surgery and radiation are impractical for addressing distributed cancer.  Systemic therapy, including most methods of administering chemotherapy, works throughout the body, and are thus more appropriate for treating widespread cancer.   Aside from conventional chemotherapy, hormone therapy and targeted chemo treatment count as systemic therapy.