First of all, there is short-term time, which, in case you have heavy enough treatments (surgery, radiotherapy, chemotherapy...) becomes suddenly plentiful, as in most cases continuing to work is out of the question.
Once the heaviest procedures are done and dusted, even if one suffers from residual pain and significant side-effects, you find out quickly that you still have a lot of time on your hands, day after day for weeks or months. It's even much better in Europe and other places, if you can benefit from fully paid medical leave.
So, what do you do with this extra time on your hands?
Well, first of all it depends on your physical state, if you're valid enough, try traveling, relive one of your old hobbies, wherever it can be, learn a new language, learn to play music, or learn another instrument if you already play, anything that can improve your self-image, make you move, make you feel emotions is good. In particular if it gets you out of your home and obliges you to socialise, meet people, restart new friendships...
Anything except self-pity, depression and staying alone, inside, and growing deeper into fear and loathing.
But that's the short-term part, the paradox here is that, for most people, it's clearly visible that while short-term time has increased, long-term time is either seriously limited, based on the diagnostic, or at the least threatens to be shortened.
How do you reconcile a diagnostic of six to twelve months to live, together with a fully free schedule, apart from some palliative treatments?
You can start your bucket list, settle your affairs for your family and loved ones, relink with parents and relatives, friends that moved or live in other countries.
But what if the diagnostic is better, the horizon is two, five years, maybe ten and more?
Are you ready to make the changes in your life that will ensure that you will live the rest of your (long) days in a more fulfilling way? In a more meaningful way? Are you still afraid of changes, once you've beaten something as dangerous as cancer?
Today's the first day of the rest of your life, make the best of it!