What does the term "cancer recurrence" refer to?

The term "cancer recurrence" specifically refers to the return of cancer after a patient has undergone treatment and was initially thought to be cancer-free. This can happen when some cancer cells are left in the body post-treatment and later grow into detectable tumors again. Recurrence can occur months or even years after the initial treatment, and it can happen in the same place as the original cancer (local recurrence) or in different parts of the body (distant recurrence). Understanding this concept is crucial for oncologists and patients alike, as managing recurrence is a significant aspect of cancer care and may involve different treatment strategies compared to the initial cancer diagnosis.