Prognostic assays in multiple myeloma: correlated with flow cytometry.

DNA ploidy of plasma cells in bone marrow has been indicated to play a role in treatment response of multiple myeloma. Therefore, a prospective study was done to test this correlation. Univariate DNA flow cytometry was done on 13 proved multiple myeloma patients. Patients aged below 50 years showed hypodiploidy, irrespective of 'S' phase population, where as all patients above 50 years had diploidy or hyperdiploidy, except for one patient. Early stage patients (I & II) with less than 25% plasma cells in bone marrow were all aneuploids. Patients belonging to advanced clinical stage with more than 60% plasma cells in bone marrow with aneuploidy, especially hyperdiploidy (DI > 1.15), carried a poor prognosis. It was difficult to correlate the 'S' phase fraction with other parameters from the present data. Further study with BrdU labelling to determine the proliferative status of the 'S' phase cells is needed.