Pseudo-Pelger Huet Anomaly Induced by Medications: A Comparison of Twelve Cases with Myelodysplastic Syndromes Featuring Pseudo-Pelger-Huet Anomaly
E Boswell, CM Lu, Q Huang, E Wang. Duke University Medical Center, Durham, NC; UCSF Medical Center, San Francisco, CA; City of Hope National Cancer Center, Duarte, CA
Background: Pseudo-Pelger-Huet anomaly (PPHA) has recently been documented in association with exposure to transplant medications and other drugs. This iatrogenic neutrophilic dysplasia resembles hereditary Pelguer-Huet anomaly or PPHA seen occasionally in myelodysplastic syndrome (MDS), but is reversible with termination or adjustment of medications. Here we compare iatrogenic PPHA with MDS featuring a PPHA component.
Design: Twelve cases of iatrogenic PPHA and 9 cases of MDS with PPHA were identified from our bone marrow database. Cytogenetic studies were performed in 9 iatrogenic PPHA cases and all MDS cases. A molecular engraftment study was performed in 3 bone marrow transplant cases.
Results: Of the 12 cases of iatrogenic PPHA, 5 were seen following bone marrow transplant for acute myeloid leukemia (AML). Three cases were found with chronic lymphocytic leukemia (CLL), 2 in solid organ transplant recipients and 2 in other disease states. Three bone marrow transplant biopsies demonstrated donor cell engraftment by cytogenetics or molecular study, confirming the donor origin of PPHA cells; all the remaining 9 patients recovered normal neutrophilic segmentation after medication adjustment. The 9 MDS cases with non-iatrogenic PPHA included refractory anemia with excess blasts (3), refractory anemia (2), therapy-related MDS (2), and refractory cytopenia with multilineage dysplasia and refractory anemia with ringed sideroblasts (1 each). All 9 cases of MDS demonstrated at least two additional marrow abnormalities not observed in iatrogenic PPHA, including hypercellularity (8/9), morphologic dysplasia (8/9), clonal cytogenetic abnormality (7/9) and increased blasts (3/9). The median proportion of circulating PPHA cells was 31% (range 11%-94%) in iatrogenic PPHA versus 9% (range 2-28%) for the MDS cases. In comparison with non-iatrogenic PPHA in MDS, the iatrogenic PPHA cell nuclei were more uniformly unilobate and displayed clumped chromatin.
Conclusions: Iatrogenic PPHA shows a higher proportion of circulating PPHA cells and more homogenous morphology than MDS. Other characteristic marrow abnormalities observed in MDS were absent in iatrogenic PPHA. Morphologic findings, cytogenetic and/or engraftment studies can aid in distinguishing relapsed MDS from iatrogenic PPHA in bone marrow transplant recipients.
Wednesday, March 24, 2010 1:00 PM
Poster Session VI # 198, Wednesday Afternoon