Can venesection also help CMML?

I have high haemocrit (57%) and high haemoglobin (180) due to secondary polycythemia Vera which consultant says is due to sleep apnoea and have been using CPAP for a year but it continues to rise slowly.

i also have a raised monocyte count (every blood test done since 2019 => 0.97) although to my kind these are explainable (influenza, multi-organ failure, chest infections, pacemaker fitted, shoulder operation, throat infection. Etc.

as a result of the raised monocyte count, I  had a bone marrow biopsy, And this is appeared to reveal abnormalities in the white cells which I understand to be the presence of blasts. The consultant did not provide a detailed percentage of the blast in my blood, and I have been put onto a watch white protocol for the CMML.

Since I have a high red blood cell count, one of these suggestions made previously was venesection, Which was done prior to a shoulder operation in December however, did not go Well, resulting in nine attempts a period of three weeks to get around 750 mL of blood.

The consultant has said That he is not going to repeat the venesection, and as a result is therefore not treating the secondary polycythemia vera.

This decision concerns me since I understand that high haemocrit can lead to A higher likelihood of pulmonary embolism etc.

Whilst I would be far from enthusiastic about further attempts of Venesection, My question is if I was to have this could it help reduce the overall percentage of blasts in my blood and thus extend the period where no further action is required?

  • Hello and thank you for posting.

    I am sorry that you are feeling concerned about the decisions that your doctor has made. Unfortunately we are unable to give a medical opinion.

    What I can tell you is that Venesection simply removes circulating blood in situations where there is excess red cells or iron. It does not treat abnormal bone marrow behaviour and is not considered a disease modifying treatment.

    Having an increased percentage of blasts, whether in blood or marrow means the marrow is producing more malignant cells. Removing blood does not ultimately reduce the blast production that is happening, or affect the blast percentage in a lasting way.

    Any very small short‑term change seen on blood counts after venesection is purely numbers, not necessarily the actual biology of what has happened in the bone marrow.

    Instead Venesection could actually increase symptoms, like fatigue, stimulate the bone marrow further and/or lead to misleading blood results.

    Do discuss this further with your team to understand the decisions they have made around your care and treatment.

    It might be that you would like a second opinion to help you understand further what the doctor has suggested. This page from our website might be useful.

    Take care, and if you would like to talk to our nurses on the helpline the number to call is 0808 800 4040. Lines are open Mon-Fri, 9-5.

    Sarah.