Modifications in the classification of primary myelodysplastic syndromes: the addition of a scoring system.

A retrospective series of patients with the primary myelodysplastic syndrome has been reviewed and the survival updated. A scoring system is proposed that has advantages in predicting survival outcome. The importance of either dysmegakaryocytopoiesis or dysgranulocytopoiesis is emphasized because of its prognostic impact on leukaemic progression. Over 50 per cent of the patients die from either acute leukaemia or consequences of defective marrow production of granulocytes and platelets. Although only a few cases were included, the RAEB-T group has a very poor outcome and appears much closer to FAB M2 in biologic behaviour than RAEB. Both the criteria for the FAB subtypes and the scoring system can be applied easily in each case of myelodysplasia. Of the 56 patients only 9 were still alive as of April, 1984. Eight of these were in the RA-S and RA categories (or using the scoring system grouping 7 were group 1). All of the 16 patients who progressed to overt AML died within 4 weeks, and none was treated with chemotherapy. Of the remaining 31 patients, half died as a result of infection and/or haemorrhage and the remainder from apparently unrelated causes (cardiovascular, carcinoma, renal failure). These latter deaths are not surprising in light of the median age of 72 years.