Non-secretory multiple myeloma: Diagnosis and management.

Multiple myeloma (MM) is one of the most commonly diagnosed blood cancers. One criterion for the diagnosis of MM is serum and/or urine monoclonal protein produced by clonal plasmocytes. However, about 1-2% of MM cases do not have monoclonal protein. If other diagnostic criteria are present, the possibility of a diagnosis of non-secretory MM should be considered. As the different types of non-secretory MM depend on the underlying cause, the current definition is considered insufficient. Currently, both the diagnosis and treatment of non-secretory MM are the same as those of secretory MM. Due to the rarity of non-secretory MM, most findings are from retrospective studies on small groups of patients and case reports. The method of monitoring the effectiveness of MM treatment remains a problem, as it is usually based on the assessment of the percentage of clonal plasma cells in the bone marrow and imaging studies.