Myeloma

What Is Myeloma—and Is It a Blood Cancer?

Multiple myeloma (MM)—often simply referred to as myeloma—is indeed a type of blood cancer, one that specifically affects plasma cells, a mature form of white blood cell responsible for producing antibodies. In myeloma, genetically abnormal plasma cells multiply uncontrollably within the bone marrow, producing large amounts of a single type of antibody (a “monoclonal protein”), crowding out healthy blood cells, and causing damage to bones, kidneys, and other organs

It is classified as a hematological lymphoid malignancy of tumour plasma cells. It is unquestionably within the spectrum of blood cancers, along with leukemia and lymphoma.

How Does It Arise? Biology and Classification

Multiple myeloma develops through a multistep biological process driven by genetic changes and interactions with the bone marrow microenvironment. It's genetically heterogeneous and remains incurable mainly due to relapse or treatment resistance.

Diagnosis uses the International Myeloma Working Group (IMWG) criteria, which require:

≥10% of plasma cells in bone marrow being clonal.

At least one myeloma-defining event, which may include end-organ damage captured in the CRAB acronym: Calcium elevation, Renal dysfunction, Anemia, or Bone lesions, or biomarkers indicating high likelihood of progression.

Myeloma is the second most common blood cancer after lymphoma globally, accounting for approximately 10% of hematologic malignancies.

This article is for education through My Blood My Health and is not a substitute for medical advice. If you have concerns or symptoms, please consult a qualified healthcare professional.

Epidemiology&CanadianPerspective

Canada: Roughly 4,100 Canadians are forecast to be diagnosed with multiple myeloma annually, and around 1,750 die from it.

Prevalence data show that about 1 in 2,505 Canadians are living with myeloma as of 2022. The annual incidence equates to about 5.2 new cases per 100,000 people, representing approximately 1.3% of all cancers and 10% of blood cancers in Canada.

A large population study found an incidence in Canada averaging 54.3 cases per million people per year (≈5.43 per 100,000), with a steady annual increase of nearly 0.96 cases per million per year. The mean age at diagnosis was 70 years, with about 54% of cases in men.

Worldwide, in 2020, nearly 175,000 people were diagnosed, and 117,000 died from multiple myeloma. In the US, projections estimate around 35,000 new cases and 12,000 deaths in 2023

Approximately 170,405 Americans were living with the disease in 2020. Survival has improved: about 60% survive at least 5 years, and around 34% live 10years or more after diagnosis

The disease typically affects individuals around age 60 or 69, is more common in men, and is rare under age 40