Waldenström macroglobulinemia

Waldenström macroglobulinemia
Synonyms	Lymphoplasmacytic lymphoma
Pronounce	N/A
Specialty	N/A
Symptoms	Fatigue, bleeding, neuropathy, vision problems
Complications	Hyperviscosity syndrome, anemia, cryoglobulinemia
Onset	Typically in adulthood
Duration	Chronic
Types	N/A
Causes	Unknown, possibly genetic and environmental factors
Risks	Family history, age, sex
Diagnosis	Blood test, bone marrow biopsy, immunofixation
Differential diagnosis	Multiple myeloma, chronic lymphocytic leukemia, non-Hodgkin lymphoma
Prevention	N/A
Treatment	Chemotherapy, immunotherapy, plasmapheresis
Medication	N/A
Prognosis	Variable, depends on stage and response to treatment
Frequency	Rare, approximately 3 per million people per year
Deaths	N/A

Waldenström Macroglobulinemia Waldenström macroglobulinemia (WM) is a rare type of non-Hodgkin lymphoma characterized by an overproduction of monoclonal IgM antibodies by lymphoplasmacytic cells. It is named after the Swedish physician Jan G. Waldenström, who first described the condition in 1944.

Pathophysiology

WM is a lymphoproliferative disorder that involves the bone marrow, lymph nodes, and spleen. The disease is characterized by the presence of lymphoplasmacytic lymphoma cells, which are a hybrid of B lymphocytes and plasma cells. These cells produce large amounts of IgM, leading to hyperviscosity syndrome, which can cause symptoms such as blurred vision, headaches, and bleeding. The exact cause of WM is unknown, but it is associated with genetic mutations, particularly in the MYD88 gene, which is found in over 90% of cases. This mutation leads to the activation of the NF-kB signaling pathway, promoting cell survival and proliferation.

Clinical Presentation

Patients with WM may present with a variety of symptoms, including:

• Fatigue
• Weight loss
• Night sweats
• Peripheral neuropathy
• Anemia
• Hyperviscosity symptoms (e.g., visual disturbances, headaches)

Diagnosis

The diagnosis of WM is based on a combination of clinical, laboratory, and pathological findings. Key diagnostic criteria include:

• Presence of IgM monoclonal gammopathy
• Bone marrow biopsy showing infiltration by lymphoplasmacytic cells
• Genetic testing for MYD88 L265P mutation

Laboratory tests often reveal elevated serum IgM levels, anemia, and sometimes thrombocytopenia.

Treatment

Treatment of WM is tailored to the individual patient and may include:

• Plasmapheresis for hyperviscosity symptoms
• Chemotherapy regimens such as bendamustine and rituximab
• Targeted therapies like ibrutinib, a Bruton tyrosine kinase inhibitor
• Stem cell transplantation in selected cases

Prognosis

The prognosis for WM varies, with a median survival of approximately 5-10 years. Factors influencing prognosis include age, performance status, and the presence of certain genetic mutations.

Also see

• Non-Hodgkin lymphoma
• Multiple myeloma
• Chronic lymphocytic leukemia
• Monoclonal gammopathy of undetermined significance