When cancer is first diagnosed, a treatment strategy is established to eliminate it. Either one treatment type or a combination of therapy approaches is used in order to reduce the likelihood that the cancer cells can survive.

Sometimes, however, cancer cells remain after therapy. If this happens, the cancer may return. Cancer can even come back years after the initial treatment. It can reappear either in the same area of the body or in another part.

• Recurrence in the same part of the body is known as local recurrence.
• When cancer comes back in another part of the body, it is called metastasis, or secondary cancer.

In general, certain treatment strategies exist to control cases of reappearing cancer. Sometimes, it is possible to use these treatments to eliminate the cancer altogether.