Background: Chronic neutrophilic leukemia (CNL) is a rare disease and can be characterized by dysplastic changes (CNL-D) only in very few cases. It has never been described after treatment for Hodgkin lymphoma (HL).
Case Report: A 41-year-old woman, previously treated with chemo-radiotherapy for HL, presented with absolute neutrophilia, anemia and thrombocytopenia. All circulating neutrophils displayed Pelger-like features, with round-shaped nuclei. In addition, an evident clumping of chromatin into blocks separated by clear zones was observed in a significant percentage of Pelger-like neutrophils. Electron microscopy confirmed these findings. Bone marrow showed trilineage dysplasia. CNL-D was diagnosed. Nine months later, transformation into acute myeloid leukemia (M1 of FAB classification) was observed, with immunophenotype characterized by the expression of CD34, CD33, CD13, CD117 and HLA-DR. The patient died with a clinical picture of therapy-resistant disease.
Conclusions: Therapy-related myelodysplasia and acute leukemia can be observed after treatment for HL. We describe the first case of CNL-D following therapy for HL. CNL is frequently characterized by a fatal clinical course, and the presence of myelodysplastic features worsen prognosis. Thus, it is important to recognise this clinical entity in order to develop appropriate therapeutic strategies.

Keywords: Neutrophils, Hodgkin lymphoma, electron microscopy, Chronic neutrophilic leukemia, Pseudo Pelger neutrophils, acute myeloid leukemia