In a recent webinar hosted by the International Waldenström’s Macroglobulinemia Foundation (IWMF) and held on July 22nd, 2020, Dr. Jeffery Matous from the Colorado Blood Cancer Institute gave an in-depth presentation about that characteristics of Waldenström’s macroglobulinemia (WM), a rare blood cancer. The webinar primarily focused on aspects such as risk factors, clinical presentation, and what patients should know surrounding WM and the ongoing coronavirus/COVID-19 pandemic.
About Waldenström’s Macroglobulinemia (WM)
Waldenström’s macroglobulinemia, which is also known as lymphoplasmacytic lymphoma, is a rare type of blood cancer that affects two types of B lymphocytes, including plasma cells and lymphoplasmacytoid cells. A distinct characteristic of this type of cancer is the presence of a high concentration of IgM antibodies. It is a slow progressing form of blood cancer, and many patients can lead active lives. While it cannot be cured, it is treatable; some patients are able to experience years of remission without symptoms. There are only about 1,500 new cases per year in the U.S. Although it mostly occurs due to sporadic genetic mutations, a family history increases risk. Symptoms include vision loss, headaches, enlargement of the lymph nodes, liver, and spleen, bleeding nose and gums, weight loss, fatigue, and general weakness. To learn more about WM, click here.
While the webinar provided good general information about the disease, Dr. Matous did not hesitate to go more in-depth in discussing WM’s defining characteristics.
Risk Factors
In regards to causes and risk factors, Dr. Matous made it clear that the appearance of WM is mostly sporadic and hasn’t been strongly linked to any external factors. However, there is some possibility that exposure to Agent Orange (think Vietnam vets) could increase the risk. Around 20 percent of cases appear to be familial, with one first degree relative having either WM or some other type of B-cell cancer. Dr. Matous says that the link is not strong enough for family screening to be helpful, however.
A critical component of a WM diagnosis is the detection of excess immunoglobulin M (IgM) in the blood, which is produced by the affected cells. A precursor stage which is seen in some patients is called IgM monoclonal gammopathy of undetermined significance (MGUS), in which an elevated level of IgM is detected but there are no symptoms. WM isn’t treated until symptoms appear.
Complications
Dr. Matous also talked about certain complications that can appear in WM. These include IgM neuropathy (nerve damage) that doesn’t appear in all patients but can cause serious and debilitating symptoms. While this generally only impacts the peripheral nerves, WM is more rarely linked to Bing-Neel syndrome in which the central nervous system is impacted. Another complication that can occur is hyperviscosity syndrome in which the blood becomes excessively thick. This can cause symptoms such as headaches and nosebleeds.
Ultimately there is significant variation in how the disease can present itself in different patients. An ongoing area of WM research is investigating genetic mutations that appear in patients; most patients have a specific mutation affecting the MYD88 gene, but other mutations can appear as well.
WM and COVID-19
In regards to COVID-19, Dr. Matous emphasizes that WM patients are vulnerable to infection and should consider themselves “immunocompromised.” Therefore serious precautions should be taken to avoid high risk areas, such as public transportation and large stores. Dr. Matous recommends following all common guidelines such as wearing masks in public, washing hands frequently, and practicing physical distancing.
