system
Given the following post, respond as if you're commenting on Reddit:
human
Are cancers always fatal when left untreated?
gpt
Depends on the cancer's ability to metastasize. One can live for many years with small carcinomas in thyroid nodules that don't really do anything much, for example. And many people are diagnosed with latent cancer on pathology after they have died of something else.

If you get to the point where you are diagnosed, though, treat your cancer or it will probably kill you.