Diagnosis and Treatment of Polycythemia Vera: A Review

Importance: Polycythemia vera (PV), a myeloproliferative neoplasm characterized by an increased red blood cell mass and increased risk of thrombosis, affects approximately 65 000 people in the US, with an annual incidence of 0.5 to 4.0 cases per 100 000 persons.

Observations: Erythrocytosis (hemoglobin >16.5 mg/dL in men or >16.0 mg/dL in women) is a required diagnostic criterion, although thrombocytosis (53%) and leukocytosis (49%) are common. Patients may have pruritus (33%), erythromelalgia (5.3%), transient visual changes (14%), and splenomegaly (36%) with abdominal discomfort. More than 95% of patients have a JAK2 gene variant, which helps distinguish PV from secondary causes of erythrocytosis, such as tobacco smoking or sleep apnea. Among 7 cohorts (1545 individuals), the median survival from diagnosis was 14.1 to 27.6 years. Prior to or at the time of PV diagnosis, arterial thrombosis occurred in 16% of patients and 7% had venous thrombotic events, which could involve unusual sites, such as splanchnic veins. PV is also associated with an increased bleeding risk, especially in patients with acquired von Willebrand disease, which can occur with extreme thrombocytosis (platelet count, ≥1000 × 109/L). All patients with PV should receive therapeutic phlebotomy (goal hematocrit, <45%) and low-dose aspirin (if no contraindications). Patients who are at higher risk of thrombosis include those aged 60 years or older or with a prior thrombosis. These patients and those with persistent PV symptoms may benefit from cytoreductive therapy with hydroxyurea or interferon to lower thrombosis risk and decrease symptoms. Ruxolitinib is a Janus kinase inhibitor that can alleviate pruritus and decrease splenomegaly in patients who are intolerant of or resistant to hydroxyurea. About 12.7% of patients with PV develop myelofibrosis and 6.8% develop acute myeloid leukemia.

Conclusions and Relevance: PV is a myeloproliferative neoplasm characterized by erythrocytosis and is almost universally associated with a JAK2 gene variant. PV is associated with an increased risk of arterial and venous thrombosis, hemorrhage, myelofibrosis, and acute myeloid leukemia. To decrease the risk of thrombosis, all patients with PV should be treated with aspirin and therapeutic phlebotomy to maintain a hematocrit of less than 45%. Cytoreductive therapies, such as hydroxyurea or interferon, are recommended for patients at high risk of thrombosis.

Author/s:

Douglas Tremblay, Marina Kremyanskaya, John Mascarenhas, Ronald Hoffman

What Is Childhood Leukemia?

Erin Blanchette — Mon, 19 Feb 2024 16:59:17 +0000

Date Added:

February 19, 2024

Journal/Publication:

JAMA

Publisher:

American Medical Association

Publication Date:

February 9, 2024

URL:

What Is Childhood Leukemia?

Type:

Patient Education Materials

Format:

Article

DOI (1):

10.1001/jama.2023.24648

Keywords

PMID (1):

38334982

MeSH

Bone Marrow

Precursor Cell Lymphoblastic Leukemia-Lymphoma

Leukemia

Myeloid

Acute

A summary for patients of our current understanding of childhood leukemia. James W. Mold, MD, MPH

Free full text

View

Childhood leukemia is the most common type of cancer that affects children. Leukemia is a cancer of white blood cells that starts in bone marrow (the soft center part of bones), which produces blood cells. Once a leukemic cell develops, it multiplies quickly in the bone marrow and can prevent healthy blood cells from forming. Leukemic cells can spread to various parts of the body, including the fluid that surrounds the brain and spinal cord (cerebrospinal fluid) and other organs such as the liver and kidneys. The cause of childhood leukemia is usually unknown, but in some rare cases, inherited genetic factors may play a role in development of childhood leukemia.

Author/s:

Jenny Ruiz, Colleen Mathews, Erika Friehling