Method: flow cytometry with propidium iodide (PI) staining
DNA content of plasma cells can be classified as:
(1) diploid
(2) hyperdiploid
(3) hypodiploid
Correlations with hypodiploidy:
(1) poor response to chemotherapy
(2) poor overall survival (according to Morgan et al: 2.5 months versus 24 months for diploid or hyperdiploid)
(3) irregular nuclear shape of bone marrow plasma cells
Additional risk factors for poor prognosis:
(1) deletion of chromosome 13
(2) myelodysplastic-type cytogenetic abnormalities
(3) deletion of p53 by FISH (chromosome 17)
(4) c-myc (chromosome 8)
(5) t(4;14) or t(14;16) involving immunoglobulin heavy chain (IgH) gene at 14q32
A patient with high risk features is less likely to benefit from high-dose chemotherapy with autologous stem cell transplant.
