I have a diagnosis of CALR positive Primary Myelofibrosis with ASXL1. My haematologist has suggested I have a JAK v617f disease burden test but that this test isn’t available with NHS funding (at least in my local health authority area). Therefore I am considering self funding to have the test done privately but I am wondering what the benefit of the test would be ( my haematologist did try to explain but I didn’t really understand)
Are any of you wonderfully knowledgable people out there able to explain this to me in a more ‘basic’ and understandable way?
Thanks in advance
Garry
Written by
ConniesDad
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JAKv617f is the most common of the MPN driver mutations. It is not mutually exclusive if you have the CALR mutation, though it is rare to have both. It would be important to know if you had both. I would expect that you would have had the basic JAK2 mutation test already done. This is standard assessment protocol. If you are not JAK2 positive, I cannot understand why the doc would want to do a JAK2 mutant allele burden check. I also cannot understand why the JAK2 Mutant Allele Quantitative Analysis would not be covered by NHS. This is standard assessment protocol for anyone with the JAK2 mutation.
Hunter has pretty much already covered most of this anyways... However, as I am also blessed w/ a CALR+ Type2 mutation, & ASXL1+, and therefore you I have a few things in common...
As Hunter already mentioned above, it is rare that people are usually found to have both, although, I have heard of them sometimes morphing and changing over time...
In any event, usually JAK2 is tested for first, and if not present... that is when they commence searching to detect either one of the CALR variants, and or MPL...
Seeing as you already know that you are CALR+, I am not so sure that I would even bother to have a further test...
JAK2, CALR & MPL, are what are known as 'Driver' mutations, and they are attributed as one of the underlying causes of our wonderfully rare blood cancer conditions...
On the other hand, ASXL1+, is one of what they term as High Risk (HR) mutation... As I mentioned above, I also have this HR, and I am still trucking along now for circa 4+ years since mu diagnosis in 2016... So do try not to be overly bothered by this discovery, how we take care of ourselves really matters too... as does diet & exercise etc...
Not entirely sure how the NHS conducts and levies for those tests ... (?) Perhaps ask Maz if she might be able to shed some further light for you about this for the UK experience etc...
Hunter is from the States, & I am from the wonderful Land of Oz... So things might be just a tad different, here & there etc...
Garry, do you have any troubling symptoms, and what age might you be please?
Personally, I am (61yo), Post ET / MF, CALR+ Type2, w/ ASXL1+, and Von Willebrands Syndrome (VWS - acquired?) Type 1 or 2?
My BMB was initially Grade2, and that was why I was reclassified to MF.
Hence, depending somewhat on answers to above questions, having a 'Bone Marrow Biopsy' (BMB), procedure might be worthwhile...? I am not sure how they are funded over there either... Again, I would probably be asking Maz, (MPN Voice Coordinator), for a bit of advice...
I’m 54 years old and was only diagnosed in April this year following a ct scan which identified an enlarged spleen. I had a bmb which led to the diagnosis of PMF and a grade 3 fibrosis. The following blood tests showed JAK2 negative and then further tests revealed CALR + with ASXL1 + and favourable karyotype. I have had post showering pruritis for a number of years and some pain associated with the enlarged spleen. I also have increasing fatigue and occasional pain in my bones
My haematologist has started me on PEG interferon but at a low dose of 90mcg every 6 weeks. I’ve only had one dose so far and seem to have tolerated this fairly well other than increased fatigue.
I have read that although my primary mutation is CALR, this does affect the JAK-STAT pathway so I wondered if the JAK v617f test related to this?
All the so-called 'Known Driver' mutations, all affect the JAK-STAT Pathway, correct.
So therefore it doesn't really matter in my own mind whether that is via JAK2, CALR or MPL. My understanding is that determining the allele burden is considered an extra type of test. However, 'allele burdens' per se can and do change over time w/ treeatment, but obviously, we are all different too...
However, if I were you I would be enquiring after receiving a prescription for Ruxolitinib (aka Jakafi). While some have hopes of a molecular reversal w/ Pegasys. I have also experienced a small but significant reduction in my bone marrow scarring from Grade2 down to Grade1...
I have been taking Jakafi for over three years now, and it has reduced my symptom burden enormously, and in a sense given me back my life, which I had feared was no longer possible to be anything resembling normalcy etc...
Jakafi also reduced my spleen, and pruritus quickly became a thing of the past...
It is also good to know that you also have a 'favourable karyotype' as do I...
If you look after yourself Garry, (diet & exercise etc), you just might live forever...
Thanks for that Steve. Not bothered about forever tbh but a ‘ripe old age’ would be good. I have a fairly good diet due to type 2 diabetes management and also keep active too.
My haematologist said that Jakafi isn’t available for me currently as I am rated as intermediate 1 and it is only funded by NHS for intermediate 2 or high risk patients. So I guess I’ll have to wait until I get worse before I can get better!
Hi Connie's dad. I am PV jak 2 positive and was changed from hydroxycarbomide to Ruxolitinib by my consultant. At the time my spleen was 15cm, white cells 30 and grade 1 fibrosis. Been on it a year and whites are now hovering around 20, spleen pain and itching gone. I'm in Norfolk UK. Wonder if it's a postcode thing why you can't get it. More likely your doctor is putting saving money before your health. I understand it is around £1,500 a box.
Your haematologist would only suggest a Jak2 allele burden test if you were Jak2 positive. The fact you have said you’re CalR+ is slightly confusing. You definitely need further clarification on this before you start parting with money. Having two ‘driver mutations’ would be extremely rare.
The Jak2 mutation is generally the first test undertaken, simply because it’s the most common. If that comes back negative only then would further testing for CalR and MPL be undertaken to determine an MPN diagnosis.
Hi, you’ve been given loads of information and advice. I can’t offer you anything along those lines.
The only thing I would consider is the consequences of such a test.
None of us know what the future holds regarding our Mpn.
I don’t know how old you are however, most of us have dreams and goals. The result of such a test might allow you to plan. Should you decide to go ahead then financial planning might be worth exploring prior to such tests as your results could influence your premiums.
I think further discussions with you heamo and Maz are very good options.
My haematologist is’the specialist’ on MPN ‘s at my local hospital haematology department and to be fair he does seem to know what he’s talking about Sometimes I struggle to understand everything he tells me though; different communication styles and expectations I think.
Hi there. Part of being a good clinician is ensuring patients understand what is being said to them.
This Forum has a policy of not commenting on / recommending doctors. I’m hoping someone in the Sheffield area might respond to you with some local insights. I note that Maz has PM’d you so I hope she has been able to provide some info.
Meantime if you haven’t already done so, do sign up for the online MPN Voice Patient Day on August 1st. Maz posted a link earlier in the week or check the MPN Voice website These events are always incredibly informative.
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