ET: What are acceptable platelet numbers?

I have ET and I've been taking 1,000mg/day of HU for 10 years.
My doctor, top oncologist at a tier one medical center just pulled me me off of HU due to the long-term cancer risks (dropping me to 500mg/day for 3 months, then zero).
He says that the latest research on HU is that it causes cancer in 8-10% of patients after multi-decades of use. He personally has had about 40 patients on HU in his career and four of them have developed cancer later in life.
I told him I was more afraid of getting a stroke due high platelet counts than I am getting cancer and he just shook his head NO for like 3 seconds.
He went to his whiteboard and drew me a graph showing very low risk of strokes even with platelet counts of 1 million or more, and the cancer risk from long-term HU is closer to 8 to 10%.
No more Hydroxy for me.

I have ET and I've been taking 1,000mg/day of HU for 10 years.
My doctor, top oncologist at a tier one medical center just pulled me me off of HU due to the long-term cancer risks (dropping me to 500mg/day for 3 months, then zero).
He says that the latest research on HU is that it causes cancer in 8-10% of patients after multi-decades of use. He personally has had about 40 patients on HU in his career and four of them have developed cancer later in life.
I told him I was more afraid of getting a stroke due high platelet counts than I am getting cancer and he just shook his head NO for like 3 seconds.
He went to his whiteboard and drew me a graph showing very low risk of strokes even with platelet counts of 1 million or more, and the cancer risk from long-term HU is closer to 8 to 10%.
No more Hydroxy for me.

Wow. Thank you for sharing this.

Let's note, you have been on a very high HU dose for a decade.

While an 8-10% chance of cancer in long-term patients is bad, that HU reduces ET fatigue and headaches, and supports our bone marrow, is good.

You are so fortunate to have a top oncologist who took the time to go over this with you!

We must all ask questions to be sure our treatment is best for our individual situation.

Just curious: Is your doctor putting you on Pegasus or a JAK inhibitor?

Is he taking all his patients off HU?

There have been studies for many years looking at whether HU causes other cancers (the link to skin cancer is known), but HU has never been clearly established as a carcinogen to my knowledge.

My doc said there may be something about the ET itself or the driver gene that triggers other cancers (besides the progression to acute forms of leukemia, which has already been established and that HU does not address).

Anyway, your post is very worrying to me, but I certainly will be discussing it with my onco. It would be helpful if I could tell her which cancer center your doc is with, but I understand if you don't want to.

Trying to get the study now.
My doctor is with the oncology department of Mercy Medical Center, Springfield, MA.