I agree with Bear, you will have many options after eventual relapse.
Specialists cannot even agree how many subtypes of myeloma there are- or even if it really is just one disease. Prognosis is therefore hit and miss on an individual basis, with some patients either doing a lot better or worse than their chromosomal features and staging at diagnosis would suggest. You have had a better response than most and I’ve heard it said that the longer you live with myeloma, the longer still you are likely to survive. That’s certainly true in the early days after diagnosis as some people are so poorly by the time that they are diagnosed that they scarcely start treatment, but also true of some of the very long lived patients.
Some patients seem to have myeloma mutations which are particularly slow and indolent. Some of these patients have lived for over 20 years, even without the benefits of the induction treatments most of us, including you, have experienced. More of us should survive for 10 &
20 years with the newer treatments available, and with newer still treatments being approved and new treatment targets being identified, the hope has got to be that some of us will experience myeloma as a chronic disease (like say diabetes) rather than a killer, and a few of us may well be functionally cured by CAR-T cell therapy, or bi specific antibodies or perhaps other treatments aimed at improving our immune systems.
Myeloma does invariably relapse at the moment, but there are better treatments available than ever before, and if you are able to take part in clinic trials other options are opened up. Some UK patients end up having 6, 8 or more different lines of treatment, if you respond to them as well as you have your first line, you could well end up dying of something other than myeloma, which is what I guess our haematologists want for us all.
If you harvested enough stem cells, another stem cell transplant might be very effective for you- a number of people in our local support group have had ‘remissions’ of more than 5 years from second SCTs.
Try not to worry about the future, you are more likely to relapse slowly and with warning, than for it to be sudden, requiring immediate treatment.
I hope you continue in your current remission for a long time to come, it does more recently diagnosed patients like me good to hear of long remissions after SCT.