Studies have shown that the risk of PV turning into leukemia varies:

• An extensive, modern observational study of over 1,600 patients with PV found that the 10-year risk of leukemia was about 2 out of every 100 people who developed leukemia in ~10 years [2].

1. Type of treatment

Older chemotherapy drugs such as chlorambucil or radioactive phosphorus were strongly linked with higher leukemia risk [3]. These are no longer standard treatments.

2. Long disease duration

The longer a person lives with PV, the higher the chance of progression. In younger patients, the risk accumulates over decades [4].

3. Genetic and disease biology

The JAK2 mutation typically drives PV; however, additional genetic changes over time may increase the risk of progression.

When PV progresses to leukemia, patients may develop:

• Severe fatigue and weakness
• Easy bruising or bleeding (due to low platelets)
• Frequent infections (due to low white cells)
• Rapid drop in blood counts
• Blasts (immature cells) in the blood or marrow [5]

This transformation is often sudden and difficult to treat. Survival is typically less than one year after AML develops [2].

While there is no way to prevent leukemic transformation completely, several strategies may help lower risk:

• Avoiding older, stronger chemotherapy drugs that can damage healthy cells, such as chlorambucil and radioactive phosphorus, which are rarely used today [3].
• Using modern therapies such as interferons or JAK inhibitors, which control disease without clear evidence of raising leukemia risk [6].
• Regular monitoring of blood counts and symptoms to detect changes early.

1. What is the chance of PV turning into leukemia?

Modern studies suggest a ~2% chance within 10 years. The risk increases with longer disease duration [2].

2. Does treatment increase the risk?

Yes, older chemotherapy drugs like chlorambucil were linked to high rates of leukemia. These are rarely used today [3].

3. Can young patients develop leukemia from PV?

Yes, but it is uncommon. A study of young PV patients revealed that while the risk exists, it is primarily observed after a prolonged disease duration [4].

4. What are the warning signs of PV turning into leukemia?

Falling blood counts, frequent infections, unexplained bruising/bleeding, and new blasts in the blood may indicate transformation [5].

5. How is leukemic transformation treated?

Treatment is challenging. Options may include chemotherapy, clinical trials, or stem cell transplant in select cases, but outcomes remain poor [6].

1. Wasserman, L. R. (1954). Polycythemia vera – Its course and treatment: Relation to myeloid metaplasia and leukemia. Bull NY Acad Med, 30(5), 343.
2. Finazzi, G., et al. (2005). Acute leukemia in polycythemia vera: analysis of 1638 patients. Blood, 105(7), 2664–2670
3. Berk, P. D., et al. (1981). Increased incidence of acute leukemia in PV associated with chlorambucil therapy. NEJM, 304(8), 441–447.
4. Passamonti, F., et al. (2003). Polycythemia vera in young patients: risk of thrombosis, myelofibrosis, and leukemia. Haematologica, 88(1), 13–18.
5. Passamonti, F., et al. (2005). Leukemic transformation of PV: a single-center study of 23 patients. Cancer, 104(5), 1032–1036.
6. Tefferi, A., Vannucchi, A. M., & Barbui, T. (2021). Polycythemia vera: historical oversights, diagnostic details, and therapeutic views. Leukemia, 35(12), 3339–335.