What does out of remission mean?

Variable: "remission" is a tricky word/concept. A simple definition is no evidence of disease (ned). However, with newer molecular detection methods we can find tiny amounts of cancer. This may or may not become clinically significant -- that is relapse. Also, you can have a remission in one area (eg lymph nodes), but relpase elsewhere. Also, some cancers in "remission" are likely cured and others not.

Relapse: Out of remission means that a cancer that was in remission after therapy has relapsed.