Hi Stephen,
Not my opinion. See below:
https://uihc.org/health-topics/chronic-myeloid-leukemia-cml
From the article,
"What are the symptoms of CML?
Because CML is, by name, a chronic leukemia, it may take quite a while before symptoms start to show—people often live many years without knowing they have CML."
I was told by M.D. Anderson that CML is a slow cancer in chronic phase and takes years to develop. Once blast phase transition occurs (again years after chronic phase has initiated), then CML can progress quickly. Over 85% of patients are diagnosed in chronic phase. Many who are diagnosed, their CML is discovered through a routine blood test and can be caught early, but still years after CML started. There were no physical symptoms at the time.
The chronology of CML starts with blood stem cells mutating into bcr-abl (9;22 translocation). There is debate on how many cells are needed to mutate at the start to sustain the disease. Radiation is a known trigger of CML. During CML expansion and growth, the body (spleen), manages the disease without the patient knowing. This is what takes years. There comes a point when physical symptoms appear - enlarged spleen, night time sweats,low grade fever. By this time, WBC's have become largely leukemic and in great numbers. It is at this point when treatment starts and the disease is often brought under control.
A key point to keep in mind - a thought experiment if you will. Recall your own treatment chronology.
How soon after you started treatment did you feel well again? In my case, in less than a couple of weeks I felt great again. WBC's dropped quickly to normal and all symptoms disappeared. This is the so-called hematological remission. However, my FISH level was 85% and PCR over 100%. In other words, I was loaded with CML, but felt fine. Many months later my FISH went to zero, so-called cytogenetic remission and an important milestone, but PCR still showed 'residual' disease. During my odyssey I had to stop treatment for a time due to severe myelosuppression. It took months before blood counts rose sufficiently to near normal. Eventually I became "undetected" and I stopped treatment to test durability. It took nine months before my PCR moved up 1/2 log - FISH still zero. I know several patients who went through pregnancy - had to stop treatment and their CML rose one or two logs, but no symptoms whatsoever and their blood counts remained normal. It is because CML is slow (only in chronic phase) that doctors who are skilled know they have time to work out an individuals personalized treatment plan involving which drug and at what dose. And while CML is "growing", a simple blood test won't show that there is anything wrong. Only when the body loses control do the WBC's start to explode in number. It's the high white blood cell count that first alerts a doctor that something is wrong.
In summary, when a person sees a doctor complaining about symptoms for the first time, their CML was "started" years earlier. Not until disease burden is so high (FISH often 100%), and the body loses ability to manage that they feel sick. Are there exceptions? No doubt. But for most, this is the chronology.
I had a series of cat scans in 2001 around my hips (large blood forming bones). Nine years later, I was diagnosed with CML. I will never have a cat scan again.