ET

[jodary]

Although I was diagnosed with ET over 10 years ago, I only know I am JAK2 negative. I have read posts on here about others being triple negative or having other diagnoses one I remember is CALR. Are these diagnosed by BMB ? I feel I don't have as much information as others but don't know how to ask at my next clinic visit. I don't know what I need to know, if you understand what I mean .

[EPguy]

The three "driver" mutations are Jak2. CALR, and MPL, or none at all. We usually get this info by blood test. But you can also get it by BMB, hence some confusion.

Another complication is there are two types of Jak2, Exon 12, or V617F (Exon 14) Exon 14 is the common one you likely got tested. If you were negative for Exon 14 they should be testing for all the others. (CALR, MPL, Exon 12)

BMB can be useful if your Dx is unclear, for future reference to monitor changes, and other reasons as ordered by your Dr. But many members and their Drs do not get/suggest BMB.

[jodary in reply to EPguy]

Hi, I did have a BMB when I was first diagnosed which was about 10 years ago. My diagnosis was ET JAK2 negative. I didn't know until reading on here there were any others. I wouldn't like to repeat the BMB unless it was absolutely necessary. If it could be decided with a blood test . Does it make any difference to treatment diagnosis or outcome if you are tested for the other mutations? In other words is it worth me asking? Thank you for your reply

[EPguy in reply to jodary]

You can get your mutation results from a blood test.

With interferon therapy and some other agents in clinical trials the various mutations can be reduced. I see in prior posts you were considering PEG. Have you started that?

So one reason to get a gene test is for future reference, if you are or will be on a therapy that can improve it you need a starting comparison to know. If you are taking PEG I would suggest the test if Dr agrees. It also may be useful for treatment decisions at some point. For example there is research into gene therapy that would be specific to CALR if it were to succeed. (latest very prelim results were not brilliant).

[jodary in reply to EPguy]

My haemo team more or less said I couldn't have peg because I have aunderactive thyroid. My understanding was that it can affect your thyroid function and you need thyroid monitoring if you take peg. Mine is monitored anyway so I don't understand their reasoning unless it's cost. I am currently on HU .

[EPguy in reply to jodary]

I agree that many of the INF risks are addressed by frequent monitoring. This includes liver etc.

This has alot of recent info on thyroid and INF and indicates it can be permanent esp if not closely tracked:

<<There are three different types of thyroid dysfunction associated with IFN treatment: (1) autoimmune (often subclinical) hypothyroidism; (2) destructive thyroiditis; and (3) Graves' hyperthyroidism. These abnormalities can occur at any time during IFN therapy, from as early as 4 weeks until as late as 23 months after initiation,[6,9] and there is no clear difference between the three types, with a median date of onset of 17 weeks after start of IFN treatment.[10] Pooling of several studies shows that hypothyroidism seems to be more frequent than thyrotoxicosis...From these data it appears that Graves' disease is the most common cause of IFN -associated hyperthyroidism.>>

medscape.com/viewarticle/45...

I believe the thyroid studies were with hepatitis patients typically on 180mcg/week. That is a very high dose for MPNs. Many risks are proportionate to the dose, so if one starts with low dose and checks frequently as you already do it should allow for trying INF. But all this requires close discussion with your Dr.

I think you're right that it's also the cost. Each country and system has different hurdles there. And if you're testing showed no mutation it might bias them toward not approving it; this might be a reason to get that extra gene test, a positive result gives another target for INF. But I can't guess NHS mysteries.

[Elleuno]

Totally understand, very little is explained by the Heamotolgist and my experience is to ask a lot of questions, particularly from the specialist nurses as they tend to have more time to explain things to you. It is a complicated condition with a lot of variants. I think they get a much clearer picture after a BMB. However, I am learning all the time, nearly 3 years since DX. You’ll also get a lot of helpful info on here which will help you to build a better picture of what is going on.

[Vtr1000]

Hi jodary, I also have an under active thyroid. When I spoke with the Dr about active treatment they were not keen for me to go onto peg. A few discussion/tests later I was allowed to go onto peg. So far it’s been a positive outcome. I did have to do a fair bit of persuading.

[jodary in reply to Vtr1000]

Thats really interesting thank you for that. I am currently on 500 HU daily and have no side effects. I have said I'm not willing to take more. I am so undecided about pushing to change to peg in case I get side effects. On the present dose platelets came down to begin with from over 1000 to 700s but then have stuck. Latest test they were 671. They want me to increase dose but I've said no. Its really difficult.

[Vtr1000 in reply to jodary]

I started out with ET Jak2 + and now have PV. With the ET I was put on hydroxy, the dose kept being increased over a year. The platelets dropped slightly, but not enough for the side effects. The fatigue was a real problem, they were going to increase again and I said no. At this point they got a second opinion, I then went to wait and watch as “there wasn’t a suitable med” with my other underlying conditions. Time goes by and I upgraded to PV, not long after I cut myself well enough to have 2 stitches and had the appreciation of how sticky my blood was. Next telephone apt I asked to start treatment, anagrelide was there first choice. I wasn’t keen, but went for the tests. Next apt we discussed both anagrelide & pegasys. I then had a face to face apt where again we discussed treatment options, I said I’d rather try pegasys which I’m very happy with as my platelets have finally dropped to 411 at my last test. For me the side effects of pegasys are none existent compared to hydroxy. Good luck with whatever you decide.

[EPguy in reply to jodary]

It is common to need more than 500 HU, I needed slightly over that to feel ok but with some of the usual side effects.

You are at a choice of risk with more HU vs risk with PEG. One reason to consider PEG, if the thyroid works out ok, is the potential long term benefits INF has that HU dos not. That was the reason I switched even as HU was working well.