Blood Test vs. Bone Marrow Biopsy

[Sheena2020]

Hi! When I was diagnosed in November 2020, I was given a blood test to determine that I have a JAK2 mutation and Polycythemia Vera. I even went to an MPN specialist and they did not order a BMB either. What are your experiences with this? Have you had one or the other or both? Does anyone know what the difference is between the two tests for diagnosis?

[FAM_KT]

Hi Sheena, I am the same Jak2 mutation and diagnosed with ET in 2019 through a blood test and not by BMB. I have discussed with my consultant regarding a BMB which he did discuss with me when we found out my results. He informed me that if my treatment did not bring my platelets down and under control or my other blood counts started to show abnormalities then it would be considered. But if it is something you wanted I would raise it with the specialist - they are the best people to give answers to the reasoning behind why. Take Care

[Sheena2020 in reply to FAM_KT]

Thank you for your response! I asked my hematologist/oncologist before and do plan to ask again. For now everything seems to be in control with the Hydroxyurea I am taking.

[Franju in reply to Sheena2020]

I had a BMB about 10 years ago and my advice would be, don’t have one unless you have to. Very painful.

[Sheena2020 in reply to Franju]

Thanks for the info. I will keep that in mind!

[hunter5582]

I have had a MPN for 30 years. I have never had a BMB. All my hematologists, including two MPN Specialists, have said I do not need one. My diagnosis was clear from the blood tests. We will do a BMB when there is a change in the status of my PV that indicates a need to do so.

Many docs do start with a BMB at point of diagnosis. It does provide a baseline regarding bone marrow morphology, including the level of fibrosis. The key question would be what would a BMB tell you that you do not already know? And - would the answer change anything regarding your treatment?

So there is not a clear-cut answer to your question, It really comes down to whether the information gained would justify the discomfort and intrinsic risks (very low) of a BMB. This is a decision you can make in consultation with your providers.

[Sheena2020 in reply to hunter5582]

Thank you for your response! I am going to ask my hematologist/oncologist about the baseline for the level of fibrosis.

[shiftzz]

I was diagnosed 7 years ago, I had a BMB, abd that confirmed the JAK2 mutation, but they didn't record the level of mutation.Since then the NHS region are using blood tests and my consultant informed me that my allele burden was around 2%, I am due to have another JAK 2 blood test this week.

I was on low dosage hydroxycarbamide, interferon and aspirin, my hct has went below my target of 0.45 for some time and they have stopped my hydroxycarbamide, my hct has remained below, but there was a slight increase last month, fingers crossed its a blip..

They have stopped offering venesection as I've had too many, last count was 66.

After my blackout in the woods some 8 months ago, they discovered a cyst in my brain, not the cause of the blackout, but since then they have discovered that my heart can race up to 140 for no reason, all tests inconclusive so on a very low dose iof betablockers

You know how they age trees by counting the rings, in humans they age us by the number if medication we take..

Stay safe.

Oh yes, my blackout, caused this

Legs, scratches

[Sheena2020 in reply to shiftzz]

Thank you for your response! I was told that my mutation was less than 50%. Is that the allele burden? I hope your arm heals!

[Anniepops112]

I was diagnosed with ET following a JAK2 positive blood test by a general haematologist. I was registered at a MPN clinic 2.5 years later through coincidence and had a BMB as a base layer. I’ve since moved and the new hospital are really surprised I’ve had a BMB, as their practice is not to do so. I think like with most things MPN related it depends on your consultant for your program of care 🤷‍♀️

[Sheena2020 in reply to Anniepops112]

Thanks for the info!

[Bears23]

I had a bmb when first diagnosed. I’m very happy I did, years later I required a second and they used the first to compare progression. They were both ordered by MPN specialists. I fly out once a year to a well known specialist at MD Anderson. I’m thankful that both MPN specialists are will to communicate and work together. Best of luck during your journey and there are some very knowledgeable and friendly people on this site.

[Sheena2020 in reply to Bears23]

That is great that the doctors work together. Tank you for the info!

[Cja1956]

I was diagnosed with ET jak 2 in 2008 with a BMB. I had been referred to a hematologist by my gp because of high platelets. I had my second BMB in 2019, with a new hematologist, that confirmed post Et Mf intermediate 1, grade 2 fibrosis. So, in my opinion, bloodwork is important, but a BMB gives a more complete picture.

[Sheena2020 in reply to Cja1956]

I agree. Thank you for the info!

[Solyesh]

I was diagnosed with "suspected ET" in the fall of 2020. When I went to the MPN specialist, he suggested that we get a BMB to confirm. He said he usually ordered one for confirmation and also to have a baseline for the future. He also said many doctors do one to make sure one of the diseases isn't masking another (as they are all on a continuum).

[Sheena2020 in reply to Solyesh]

Thank you for the info!

[EPguy]

In simplified form, BMB shows what your marrow looks like under a microscope. They see fibrosis, celluraity, and other things visually. There is much more than that of course. It requires expert interpretation. Some of its other info, like allele burden, is avail by blood.

Did you get an allele burden?

I got BMB just after my Dx. It can help if there is uncertainty on your specific MPN. It's likely most useful as a reference point for the future as knowledge and therapies evolve and the information may be more actionable, see 2nd para below.

In

ncbi.nlm.nih.gov/pmc/articl...

marrow state can be relevant to INF therapy to adjust the dose, and monitoring only allele burden is not the full picture. This is most relevant to INF or other future therapies vs HU or for example. This 2017 study however was for only 15 patients.

<<At our institution, we encourage annual marrow examinations of our PV patients to assess cellularity and degree of fibrosis as one of the parameters we use for maintaining or changing the dose of interferon therapy. This is because we have observed persistent marrow hypercellularity and/or progressive fibrosis in PV patients receiving rIFNα despite developing a significantly reduced %V617F in peripheral blood (PB). This has therapeutic importance and relevance since increasing the dose of rIFNα may retard the progression of disease irrespective of marrow fibrosis.>>

<<Our findings add credence to recent World Health Organization criteria stressing the importance of the marrow biopsy at diagnosis, specifically recommended first by the Polycythemia Vera Study Group (PVSG).14 Whereas it may be argued that a baseline BM biopsy is not a necessary diagnostic procedure for patients with a significantly increased red cell count and a demonstrable JAK2V617F allele burden, a biopsy establishes initial degree of cellularity and fibrosis which should be used in clinical decision making during the course of the illness.>>

--

Note this later and larger study has a correlation between CMR (allele near zero) and marrow response:

ncbi.nlm.nih.gov/pmc/articl...

<<Similarly, patients with PV who have achieved CMR have experienced significant reduction in bone marrow cellularity>>

More reason to know your BM status.

[Sheena2020 in reply to EPguy]

Thank you for all the information! They told me that my mutation was less than 50%. Is that the allele burden?

[EPguy in reply to Sheena2020]

That is most likely your allele burden (AB). In other posts here we discuss a study that being under 50% has good significance.

But you should try to get a more precise number for future reference.

[Sheena2020 in reply to EPguy]

Thank you for the info. I will!

[gvibes]

Hi Sheena, I had a BMB shortly after initial diagnosis. Like some others above, I think it provided some useful baseline information in my disease understanding. A couple months later I got involved with an MPN specialist and he recommended that the preserved BM samples be sent to their lab for a separate analysis - which I did and they confirmed the first hospital interpretation (I guess everything has subjective elements). It seems like different docs treat the importance of BMB differently. Personally, since the disease is based in the bone marrow, I like the idea of someone looking at samples there. While I was pretty worried about doing it, it turned out to be a pretty easy procedure for me. Good luck!

[Beup in reply to gvibes]

Hi! I may get a BMB at my local hospital where I see my hematologist. The MPN specialist I plan to see is out of state. What are “preserved samples” that can be sent ? Are they on slides? I appreciate any feedback. Thanks!

[Sheena2020 in reply to gvibes]

I agree. Thank you for the info!

[gvibes]

Hi Sheena, I forgot to mention above, that my allele burden numbers in blood and bone marrow aspirate were significantly different (5% to 35%). Not sure why but my blood sample was taken after 8 phlebotomies and not sure if the blood chemistry was confused at that point. I keep forgetting to ask my MPN guy but I will. Take care.

[Sheena2020 in reply to gvibes]

I forget to ask some things too. I make a list but sometimes I miss a question! They told me that my mutation was less than 50%. Is that the allele burden?

[gvibes in reply to Sheena2020]

Yes, that is my understanding. Its just an estimate of the percent of mutated cells.

[Sheena2020 in reply to gvibes]

Interesting. They only told me less than 50%. Some people know a more specific number. I will ask if they have that for me!

[gvibes]

Hi, that sounds like what I did with the local hematologist doing the bmb. The local hospital created slides for their pathologist review and somehow they were preserved. I requested six months later that they be sent to the mpn hospital and they were good for that. It seemed like it was the normal routine in this kind of work. You might want to check in advance though to make sure. Good luck

[Sheena2020 in reply to gvibes]

I will. Thank you for the info. Good luck to you too!