Clinical significance of bone marrow biopsy and plasma cell morphology in MM and MGUS

Multiple myeloma (MM) is characterized by plasma cell infiltration in the b one marrow, suppression of normal haematopoiesis, destruction of bone, rena l failure and recurrent infections. The extent of organ involvement, severi ty of complications, drug sensitivity and therefore the clinical course dif fer widely among patients. Specific and reliable laboratory examinations an d especially morphology including both biopsy and aspirations are required to evaluate its aggressivity and extent. In this review of MM and its varia nts we emphasize the impact of morphology on the diagnostic and prognostic approach to MM and MGUS, and on the planning and monitoring of appropriate therapy.