Cytopathological features of multiple myeloma

Although integration of laboratory data and radiological findings are required, quantity and qualitative evaluation of plasma cells in bone marrow is still useful for the diagnosis of multiple myeloma. However, there are considerable variations in morphology of myeloma and proliferation pattern among the individual patients. Therefore, it is important to recognize cytopathological features of myeloma cells for better understanding of patients' status. For example, the finding of immature plasmablastic myeloma cells predicts the poor prognosis of the patients. In the present review, we described the cytopathological features, which is useful for diagnosis and estimation of the patients' prognosis and discrimination from reactive non-tumorous plasma cells.