Hypercellular marrow with diffuse infiltrate of medium sized lymphoid
cells comprizing approximately 30% of the marrow (see
flow studies).
Plasma cells are noted but represent less than 5% of the mononuclear
cells.
Cytogenetic studies demonstrates complex abnormalities involving chromosomes
9, 8, 11, & 14. Translocations of chromosomes 11 and 14 are most
frequently found in myeloma.
Flow
cytometry on Bone marrow