Platelets and Family History - Familial (Malignant) versus Hereditary (Benign) Thrombocytosis

[cmc_ufl]

Just thought I would post something interesting I learned in a recent discussion with my MPN specialist regarding the connection between families and platelets.

Many of you are familiar with my situation. Age 30, platelets mildly elevated 430-455 for last 10 years. Driver mutation tests all negative. Currently being evaluated as possible ET triple-negative since all other blood counts are normal and reactive thrombocytosis ruled out.

Interestingly, I recently found out my mother (age 55) also has elevated platelets, fluctuating 435-470 as far back as her CBCs are readily available (2014). Granted, she has some health problems which may or may not contribute to these numbers. Told my MPN specialist this and he told me there is definitely a connection between platelets and family history, and that it comes in two forms:

1. Familial thrombocytosis (malignant/MPN) - A lot of us are familiar with this one. Some families seem to have an increased risk of acquiring certain driver mutations (JAK2, CALR exon 9, MPL exon 10). There are many people in this forum who have reported having children or siblings with an MPN and with the same mutation they have, despite these mutations not being able to be passed on to offspring (they are only acquired somatically after birth). Familial thrombocytosis falls under the MPN category since the mutations cause clonal disorders.

2. Hereditary thrombocytosis (benign) - There are rare mutations at different locations in JAK2, MPL, and thrombopoetin (THPO) genes, as well as in many other genes, that can be passed to offspring (germline mutations). While these mutations cause elevated platelets, the important distinction here is that hereditary thrombocytosis is usually viewed as "benign thrombocytosis" rather than a myeloid malignancy. According to my specialist, leukemic transformation has never been reported with true hereditary thrombocytosis.

It is important to note that families falling under either of these categories are extremely rare, with hereditary thrombocytosis being even more rare than familial thrombocytosis.

Unfortunately, my specialist was unable to say whether he thought my family situation fell under hereditary thrombocytosis since the platelet counts of both myself and my mother are so mildly elevated, saying he would assume the platelet counts of HT families to be much higher.

See the following paper for reference:

ashpublications.org/hematol...

[Dovme]

Thanks very interesting

[PrinceA]

That interesting, thanks for sharing. I would consider this as positive news, since your mom age 55 with same range of platelets, hasn't increased and being healthy...

[cmc_ufl in reply to PrinceA]

Yes, generally speaking I think it's positive. She has a few health problems which may or may not influence her platelet counts, so it is hard to tell if this is her true baseline, but still a little piece of good news nonetheless.

[socrates_8]

Afternoon cmc_ufl...

That is indeed a truly fascinating finding... I will have a more in-depth revision of the Paper you kindly provided... Thank you

Nevertheless, the ramifications here for people who may have been previously diagnosed as 'Triple- Negative' might now not be generally received as being an adverse outcome...

Fascinating! Thanks for sharing this is indeed of great interest...

Best wishes

Steve

[cmc_ufl in reply to socrates_8]

All the best, my friend

[BeHealthy1986]

Thanks for sharing. I remember I’ve seen this in one of Professor Harrison’s publications too.

[paintbox]

Very interesting, thank you for sharing this!

[SilverET]

A great summary of the differences. Thanks, SilverET

[MPNBlog]

Thanks for sharing this. I have PV and my brother does also, though it manifests in us in very different ways. So this is of much interest to me. Thanks.

[kiwibird37]

Thank you for sharing. I am 49 year old with PV Jak2 positive. Recently started phlebotomy and Hydroxyurea. Platelets are down to 400 from 740 and Hematoctit is now under 42 from 53.My daughter was treated for Leukemia in 2017 and doing well now. I often wonder if that came from me. She is turning 15 in a couple of weeks.

It is comforting to read all of the posts and see that others get through so I thought I would share my story.

[cmc_ufl in reply to kiwibird37]

Thank you for sharing

[Hidden]

I am another with PV in the family.

My grandfather died from a stroke because of PV, his daughter (my aunt) had her PV go to leukemia and died from that. Therefore I am taking the whole thing really seriously (Jak2+) - doing all I can to stay healthy - but that fatigue really bites when it hits.

Thanks for letting us all know about this.

[Hidden]

Great stuff has helped no end,thank you.Adiewon