Hi and best wishes and prayers for you and your wife, OP.

I'll share my experience with high platelet counts so far. My platelets had been above normal for a couple of years and fairly slowly but steadily increasing with each 6-months checkup. I'm now seeing a hemotologist/oncologist with ET.

My PCP, in whom I have a lot of confidence, told me high platelet counts can be (and usually are) caused by some secondary but temporary condition, such as an infection, low B vitamins or iron, etc. He had done tests for those and a couple of other things, which were okay. He said we'd continue to keep an eye on it because some tests such as a bone marrow biopsy are invasive. But when my platelet count got to 581k he did a test for JAK-2 gene mutation, which came back positive. At that point he referred me to a hematologist/oncologist in April of this year with a diagnosis of Essential Thrombocythemia. I was 77 at the time; I am 78 now.

The specialist did not do a bone marrow biopsy, probably because the JAK2 gene mutation and my high platelet counts over time mean ET is likely. He was reassuring and positive about this disease, which he said he prefers to call a blood disorder, although technically it is a type of blood cancer, but one that doesn't spread to other parts of the body. He said they don't know what causes it nor what causes a JAK-2 gene mutation. He said I wasn't born with it, didn't do anything to cause it (afatk), and it's not hereditary (which was a relief as I have adult children and grandchildren). They don't know how to prevent it, and at present there is no cure, but it can be treated and managed. He said very rarely it can cause other blood marrow problems or turn into a form of leukemia but usually does not. Platelets are what allow our blood to clot when needed, and the high platelet count makes dangerous blood clots more likely, especially in those over 65.

He said because people over 65 are already at increased risk of blood clots, that if my count got to over 600k, I would need to take a chemo pill (presumably HU although he didn't specify), but that for now to take a low dose coated aspirin each day, which makes the platelets more slippery and less likely to clot. Blood clots that can cause strokes, heart attacks, or go to the lungs are the big danger with ET. He said my blood would need to be checked about every 3 months.

He said not to be scared by the term "chemo pill," because most people tolerate it well and it doesn't make them throw up or lose their hair.

I went for my checkup this week, and thankfully and unexpectedly my count had actually dropped to the 540s, the first time it had dropped since it began rising. Still high, but no chemo pill for now, which was a relief to me. I will continue taking the low dose aspirin everyday. I have to go back in January for a check up.

From what I've read, barring a life threatening blood clot, people with ET who are under a doctor's care usually have normal life spans. Some have symptoms such as tiredness or headaches, but so far I don't. I've also read that younger people who don't have extremely high platelet counts often don't go on any chemo but may take a low dose aspirin, if anything. This certainly isn't medical advice, as I'm not a doctor, and every patient is different. Just sharing what my doctor told me and what I've read about ET.

Discussions such as this one have been helpful for me, and there are several discussions about ET and other blood diseases here. You might want to check those. Several have posted that they've had ET for decades and are doing well.

I hope this info may be helpful and somewhat reassuring to both of you. If you and your wife don't have confidence in her doctor, I would consider getting a second opinion or changing doctors (hematologist/oncologist). Best wishes and God bless you both.