If given an initial diagnosis of curable cancer, most cancer patients probably choose to battle their cancer for at least as long as it is still regarded as curable. Even though cancer treatments involve poisoning, cutting, and burning with both temporary and permanent side effects-- some of which are disfiguring-- and risks of potentially fatal complications, the possibility of cure is sufficiently motivating for patients to undergo almost any horrors and humiliations.
In my own experience, having been classified as incurable, then possibly curable, then incurable, I think that the risk/reward ratio of undergoing draconian treatments is quite different for the curable and the incurable. For the incurable, all cancer treatments are palliative. Speaking as an incurable, I doubt that I would choose to undergo many of these debilitating treatments in hope of extending life for some short period of time; and I have no intention of doing anything voluntarily to drag out active dying. "To suffer unnecessarily is masochistic rather than heroic." (Frankl, p. 136.)
For the incurable, the struggle may not be so much with cancer as with a medical establishment pushing in good faith, if sometimes mindlessly, the next treatment; as first one, then another treatment loses its efficacy. Fortunately, my medical oncologist seems to be honoring my decision to seek quality of remaining life rather than quantity of remaining life.
Since my diagnosis and re-diagnosis as incurable, my struggle has been primarily with myself, not with cancer or the medical establishment. I must seek to use my remaining time wisely, to conduct myself appropriately, and to become a better person. If you read an obituary of me that says that I battled cancer bravely, you will know better.