I think a cancer’s treatment resistance means losing differentiating marks and becoming more and more like a stem cell.
With these evolutionary processes it’s a given, the surviving mutation was already present at the time of treatment. The higher the genetic diversity the higher the chance of said mutations. A cancer’s genome is often highly unstable, since apoptosis is disabled, so diversity tends to be high.
Metastases usually imply a good chunk of "god mode" features gained already, for solid tissue cancers (soft tissue cancers are a bit different), so it’s a bad starting point. Imaging cannot detect any tumor below say 2mm, so ultimately you never know the true stage or treatment success. So a cancer doesn’t "return", it grows above the clinical threshold again.
Treatment is kinda a genetic tautology: If it works you didn’t had a treatment resistant cancer, if not you did. Or: If you lose, you never had a chance.
With these evolutionary processes it’s a given, the surviving mutation was already present at the time of treatment. The higher the genetic diversity the higher the chance of said mutations. A cancer’s genome is often highly unstable, since apoptosis is disabled, so diversity tends to be high.
Metastases usually imply a good chunk of "god mode" features gained already, for solid tissue cancers (soft tissue cancers are a bit different), so it’s a bad starting point. Imaging cannot detect any tumor below say 2mm, so ultimately you never know the true stage or treatment success. So a cancer doesn’t "return", it grows above the clinical threshold again.
Treatment is kinda a genetic tautology: If it works you didn’t had a treatment resistant cancer, if not you did. Or: If you lose, you never had a chance.