JAK2 Mutation - Effects and Questions

Hello @ettap and welcome to Connect. It is good to see that you have confirmed your mutation twice, but are not currently experiencing any of the symptoms. If you don't mind, I am going to give a couple of quick resources in regard to a few of your questions:

- Polycythemia vera treatment: https://www.mayoclinic.org/diseases-conditions/polycythemia-vera/diagnosis-treatment/drc-20355855
- Essential thrombocytosis: https://www.mayoclinic.org/diseases-conditions/essential-thrombocythemia/diagnosis-treatment/drc-20361131

This is also from Mayo Clinic, "The mutation that causes polycythemia vera is thought to affect a protein switch that tells the cells to grow. Specifically, it's a mutation in the protein Janus kinase 2 (JAK2). Most people with polycythemia vera have this mutation. The cause of the mutation isn't known, but it's generally not inherited. Polycythemia vera can occur at any age, but it's more common in adults older than 60."

@ettap, if you don't mind sharing, have those three specific hematological disorders been discussed with you by your hematologist? Has he or she mentioned myelofibrosis? I am not a medical professional and am in no way diagnosing, but myelofibrosis can be a result of a JAK2 mutation as well.

My early Thanksgiving treat was finding out that I in fact have MF. Ugh. Interestingly, my spleen has decreased in size 18% and I have almost no blood numbers that are concerning. My platelets typically are over 450k, but almost always below 600k; elevated, but as some of you have mentioned this is not an alarming amount. However, the bone marrow biopsy did show elevated numbers in several measurements that are indicators of MF; the marrow itself had some but limited fibrosis. Dr. ordered the genetic testing on the bone marrow. That biopsy is a doozy! Might have let out a bit of "french" for the PA to hear... oops. Though there is not a grading level for MF, like in other cancers, my range is MF 0-1. It is early in the fight. Trying to wrap my mind around what this means for the near term as I have seen firsthand what the end of this can look like with my father. I am trying to focus on one day at a time.

My father passed away from a battle of myelofibrosis (MF), over 10 years after being diagnosed with enlarged spleen and 6 from diagnosis of MF. I am nearly 9 months post immunotherapy treatment for stage 3 melanoma treatment (discovered in lymph nodes without known source). During a post treatment CT scan the radiologist identified my enlarged spleen, which is not typical of melanoma, but could be a side effect of immunotherapy (very rare and limited literature). My oncologist was dismissive of the genetic potential for me to have MF, like my father. Additional observation of my spleen showed continued growth and my oncologist finally discussed with another who suggested a JAK2 mutation blood test. You can see where this is headed; I was notified yesterday that I have the JAK2 gene mutation. I am 47. I am in good health; other than previous melanoma (nearly 2 years from discovery) that I have battled and praying for a very good prognosis on that front shortly! My melanoma specialist is being reassigned and I will be headed to another hematologist that is very familiar with my family history of cancer. As my medical group sends test results directly to the patient as soon as they are received I have yet to discuss with my Dr. I presume I will have a bone marrow biopsy to determine stage, if any, at this point. I am jumping to the MF diagnose myself; treatments for early stage, ongoing studies or any suggestions to extend this wonderful life are appreciated. As with melanoma, the treatments are expanding by the day, I will not hang my head in fear, but give this godforsaken disease a damn good fight. Too much to live for to live in fear.

I'm happy to share my experience. #1. No, do not need to give blood. The Hydrea is toxic enough to kill the excess platelets. #2. I have experimented over the years to cut back a little from the prescribed dosage simply to minimize the amount of toxicity I'm consuming. My Docs have not liked this kind of fooling around with the dosage. So I've been steady at 6 days a week, no Sundays for about a year. No side effects from the Hydrea after the initial first month twenty years ago. #3. I still have no symptoms of this strange blood disorder called ET, regardless what my count is on any given day. I go every 3 months for a cbc. It puzzles me that at 72, I still feel the same with a count of 480 as I did at age 40 when I was diagnosed with a count of 800. #4. My two Docs (first one retired) have dangled the ultimate fear over me since the diagnosis, but so far my ET has not morphed into leukemia. Having no symptoms and in disbelief, I went to the Scottsdale Mayo Clinic for a second opinion at some point in the 1990s. Same diagnosis. Very disappointing because I was really convinced that nothing was wrong with me. Thanks for sharing the NIH info. I always like to run across updated information on PV,ET, and other blood disorders. You may never progress to anything more advanced. Best wishes.

I have been living with high platelets (500-680 range) since 2016. In 2017 I had a bone marrow biopsy and lots of blood work and the doctor could not find anything wrong with me. I am healthy, have no symptoms, no other major health issues except hypothyroidism which I have taken medication for for over 30 years. My primary care physician sent me to a new hematologist/oncologist. He was perplexed as to why my platelets were high. So he ordered the Jak2 mutation qualitative test and it has come back positive. I see him again this Friday. Could someone direct me as to what I should be discussing with him. I literally am having no symptoms. At the last visit he suggested the low dose aspirin but I told him that I already suffer with tinnitus and have read that aspirin can cause tinnitus and/or make it worse, so I don't know if I want to take that. The hydroxyurea scares me as to all the side effects. Any guidance from anyone on this forum would be very much appreciated. Would the blood letting be a course of treatment for me? I am 68 year old female.

I have been living with high platelets (500-680 range) since 2016. In 2017 I had a bone marrow biopsy and lots of blood work and the doctor could not find anything wrong with me. I am healthy, have no symptoms, no other major health issues except hypothyroidism which I have taken medication for for over 30 years. My primary care physician sent me to a new hematologist/oncologist. He was perplexed as to why my platelets were high. So he ordered the Jak2 mutation qualitative test and it has come back positive. I see him again this Friday. Could someone direct me as to what I should be discussing with him. I literally am having no symptoms. At the last visit he suggested the low dose aspirin but I told him that I already suffer with tinnitus and have read that aspirin can cause tinnitus and/or make it worse, so I don't know if I want to take that. The hydroxyurea scares me as to all the side effects. Any guidance from anyone on this forum would be very much appreciated. Would the blood letting be a course of treatment for me? I am 68 year old female.

My husband was diagnosed at 69, a year ago, with Primary Myelofibrosis including Jak2 mutation. A bone marrow biopsy and DNA testing confirmed this. We tried hydroxyurea but that did not shrink his spleen (as the spleen takes over the production of RBC since the bone marrow is unable to do this efficiently). Currently on Jakafi for the last 4 months, minimal side effects. We are facing a bone marrow transplant in the near future. If the spleen has not reduced in size, it will be removed and then we will proceed with the bone marrow transplant. A scary ride for sure, but it's the only cure.