How long must i be cancer free before i'm considered 'cured'?

Based on Type/Stage: Must know the type of cancer. Anywhere from immediate permanent cure to never, i.e. Always significant risk of reoccurrence. Five years disease free is the cutoff for being much less/low risk of recurrence.

Depends: All cancers behave differently based on many factors: type, stage, grade, etc... Although many cancers are able to be cured with treatments, but we continue to follow patients for many years. The follow-up guidelines vary based on the cancer type and the likelihood of recurrence. In general, we use the term "remission" instead of "cure" to indicate that recurrence is possible.