Translocations (5;17) and (7;17) in patients with de novo or therapy-related myelodysplastic syndromes or acute nonlymphocytic leukemia. A possible association with acquired pseudo-Pelger-Huët anomaly and small vacuolated granulocytes.

Twelve patients [two with de novo myelodysplastic syndrome (MDS), four with secondary MDS, five with de novo acute nonlymphocytic leukemia (ANLL), one with secondary ANLL] showed a 17p deletion resulting from translocations involving 17p: t(5;17)(p11;p11) in four cases, t(7;17)(p11;p11) in six cases, complex (5;17)(q23;p12) translocation with dicentric chromosome in one case, and t(17;?)(p11-12;?) in the remaining patient. All these structural anomalies were observed in hypodiploid clones associated with total or partial monosomy of chromosomes 5 and 7 (12 cases), monosomy 12 (five cases), monosomy 3 (four cases), and monosomy 4 (three cases). Median survival was only 3.3 months (range 3 days to 8 months). Striking features were observed in bone marrow mature granulocytes: all but one case had a pseudo-Pelger-Huët anomaly in a significant number of granulocytes, and eight patients had granulocytes with reduced size and clear cytoplasmic vacuoles. Careful cytological review of 51 patients with MDS or ANLL and various cytogenetic anomalies was performed for comparison: vacuolated granulocytes were a very uncommon finding. On the other hand, eight patients had a pseudo-Pelger-Huët anomaly, which correlated significantly with total monosomy 17 in these patients. A possible correlation between cytological anomalies and cytogenetic data is discussed, and the role of 17p in the nuclear segmentation of granulocytes is stressed.