WM World Awareness Day, also known as Waldenström Macroglobulinemia World Awareness Day, is observed worldwide every April 17. This day was established by the International Waldenström’s Macroglobulinemia Foundation (IWMF) to highlight a rare type of non-Hodgkin lymphoma that affects B lymphocytes. The condition, first described by Swedish physician Jan Gösta Waldenström in 1944, leads to the production of abnormal lymphoplasmacytic cells that produce excessive immunoglobulin M (IgM), resulting in various symptoms such as fatigue, weight loss, and enlarged lymph nodes. Activities on this day include educating the public about the disease, connecting patients and caregivers with resources, and advocating for research aimed at finding a cure. Individuals are encouraged to learn more about Waldenström macroglobulinemia, share information, and support organizations that assist patients or fund research, often using the hashtag #WMWorldAwarenessDay on social media.