The flow-cytometric DNA content of the plasma cells of patients with multiple myeloma is a prognostic factor: a single institution experience

The flow-cytometric DNA content in the plasma cells of patients with multiple myeloma has been studied as a prognostic factor and contrasting results have been found. In a group of 45 patients with myeloma from a single institution, the DNA content of the malignant plasma cells was studied by means of flow cytometry: no patients were found to have hypodiploid DNA content, 14 patients had hyperdiploid DNA, and 31 patients were found to have diploid DNA. The overall survival of patients with hyperdiploid DNA was better than that of patients with diploid DNA: 93% at 85 months and 79% at 89 months, respectively; in both groups, the median overall survival has not been reached. No correlation was found between the DNA content and the International Staging System and the discriminatory effect of the DNA content was apparent only in the patients who were not autografted. It is concluded that the flow-cytometric DNA content of the plasma cells of patients with multiple myeloma may be a prognostic factor independent of others already identified and that myeloma patients with hyperdiploid DNA content in the plasma cells may have a better prognosis than those with a normal DNA content.