I was given the option for a bone marrow test and did some research and decided against it. I was diagnosed with PV 1/22 from my labs and confirmation from JAK2 positive. The labs determine your medication and dosage and I was told that my treatment would be the same no matter what the biopsy showed. If my health declines and my numbers change, then I’ll reconsider. I do understand that some patients need that confirmation from this test due to the shock of their diagnosis. I had a few thoughts. Will it change my treatment? If the Doctor is comfortable with me not doing it, I should be too? And the cost was also a consideration. Even with insurance, it would be very costly. PV causes me to meet my deductible every year now in the first few months with phlebotomies, doctor visits and labs. Ask the right questions and do some research on reputable sites. You have to do what makes you comfortable.