Multiple myeloma is a blood cancer that arises from malignant plasma cells in the bone marrow. These abnormal cells accumulate, crowding out normal blood cell production and producing large quantities of a single abnormal antibody, called a monoclonal protein or M protein. This leads to anemia, bone damage, kidney dysfunction and weakened immunity.

Research has clarified that multiple myeloma is usually preceded by earlier, asymptomatic conditions such as monoclonal gammopathy of undetermined significance and smoldering myeloma. Genetic and molecular studies show that myeloma cells carry characteristic chromosomal abnormalities and mutations that drive uncontrolled growth and survival, particularly involving signaling pathways like NF kappa B and growth factors in the bone marrow microenvironment.

Diagnostic advances include more sensitive assays to detect monoclonal proteins, such as serum free light chain measurement, and improved imaging techniques like low dose whole body CT, MRI and PET CT to reveal early bone lesions and extramedullary disease. Bone marrow examination and cytogenetic testing help stratify patients into risk groups.

Treatment has evolved from conventional chemotherapy and steroids to targeted and immune based therapies. Proteasome inhibitors, immunomodulatory drugs and monoclonal antibodies targeting plasma cell surface markers have substantially improved survival. Combination regimens followed by autologous stem cell transplantation, when appropriate, are standard for many fit patients. Newer strategies include CAR T cell therapies, bispecific antibodies and drugs that exploit specific genetic vulnerabilities or the tumor microenvironment.

Despite major progress, multiple myeloma remains generally incurable, with cycles of remission and relapse. Ongoing research focuses on earlier detection, better risk prediction, deeper and more durable responses and approaches that may ultimately achieve functional cure in a higher proportion of patients.