Specific minor chromosome deletions in myelodysplastic syndromes: clinical and morphologic correlations.

Thirty-four patients with myelodysplastic syndrome (MDS) subtypes refractory anemia (RA) and RA with ringed sideroblasts (RA-S) (26 and eight patients, respectively) were investigated for clinical and morphologic significance of the most frequently occurring minor chromosome deletions [del(17)(p12), del(8)(p22), del(2)(p24), and del(9)(p22)]. The occurrence of 17p- was statistically significantly related to a low initial bone marrow cellularity (p = 0.01) and severe granulocytopenia (p = 0.05). A diagnosis of RA was seen more frequently among patients with 17p-, also. 17p- alone was not related to progression to RA with an excess of blasts (RAEB). The occurrence of 8p- was statistically significantly related to a higher initial frequency of bone marrow myeloblasts (p = 0.05), but not to bone marrow cellularity or initial granulocytopenia. 8p- alone was not related to initial diagnosis, but a statistically significant relation to progression to RAEB was found (p = 0.05). 2p- was related to progression to RAEB, also (p = 0.02), but not to any of the other investigated parameters. No significant relations between the occurrence of 9p- and other parameters were demonstrated. The simultaneous occurrence of 17p- and 8p- was also statistically significantly related to progression to RAEB (p = 0.02). These relationships suggest that 17p- is involved in the development of bone marrow and peripheral blood granulocytopenia and that 8p-, and possibly 2p-, interferes with differentiation of primitive granulocyte precursors and, thus, play a part in the process leading to RAEB and acute myeloid leukemia.