First, cancer isn't a single disease, but it is instead a
collection of well over 100 separate diseases. And yes, there are
many long-term survivors who have no symptoms of cancer. Much
depends upon what type of cancer they had, the stage of the
cancer when detected and the treatments given. Some cancers have
a relatively high cure rate while in others the survival rate is
dismal. There is no simple answer to your question.

Approximately 50% overall of cancer patients are cured. For some cancers
(lymphomas, skin cancers, head and neck cancer) the figure is higher. For
others high grade brain tumours, lung cancer) the figure is lower.
These are "cures" though, not just prolonged remissions.


  Question:  Is cancer curable or does it just go into remission for a
  period of time?  Are there a significant number of people who live
  10-15-20 years after cancer without a recurrence?  Thanks for your help.

Most people hesitate to use the word 'cure' However, it is possible to have
a tumour removed and be free of cancer. The problem is that cancer tends to
reappear somewhere else.
having said that I am a member of a cancer support group and have met
several people who are 15+years survivors .

    Question:  Is cancer curable or does it just go into remission for a
    period of time?  Are there a significant number of people who live
    10-15-20 years after cancer without a recurrence?  Thanks for your help.

Cancer is curable.
About 50% of cancer patients are "cured" by whatever yardstick you want to
use.