Localized blastic plasmacytoid dendritic cell neoplasm associated with progressive clonal hematopoiesis and myelodysplastic syndrome

Clara Julin; Signe Ledou Nielsen; Trine Lønbo Grantzau; Syed Azhar Ahmad; Jack Bernard Cowland; Jesper Bonde; Peter Nørgaard

doi:10.1111/apm.13486

Localized blastic plasmacytoid dendritic cell neoplasm associated with progressive clonal hematopoiesis and myelodysplastic syndrome

APMIS. 2024 Oct 28. doi: 10.1111/apm.13486. Online ahead of print.

Authors

Clara Julin¹, Signe Ledou Nielsen², Trine Lønbo Grantzau³, Syed Azhar Ahmad⁴, Jack Bernard Cowland⁵, Jesper Bonde¹, Peter Nørgaard¹

Affiliations

¹ Department of Pathology, Amager and Hvidovre Hospital, Hvidovre, Denmark.
² Department of Pathology, Herlev and Gentofte Hospital, Herlev, Denmark.
³ Department of Pathology, Rigshospitalet, Copenhagen, Denmark.
⁴ Department of Hematology, Rigshospitalet, Copenhagen, Denmark.
⁵ Department of Clinical Genetics, Rigshospitalet, Copenhagen, Denmark.

PMID: 39465574
DOI: 10.1111/apm.13486

Abstract

Clonal hematopoiesis is highly prevalent in elderly patients with blastic plasmacytoid dendritic cell neoplasm (BPDCN), and around 20% of BPDCN patients have an associated myeloid malignancy. We present a patient with localized BPDCN and concomitant myelodysplastic syndrome (MDS), previously followed for several years due to clonal cytopenia of unknown significance. Compared targeted next-generation sequencing (NGS) of the skin tumor and sequential bone marrow samples showed shared variants in ASXL1 and TET2 with a de novo NRAS variant in both BPDCN and MDS compared to preceding bone marrow samples. These findings illustrate a shared clonal origin of BPDCN and MDS resulting from progressive clonal hematopoiesis.

Keywords: Blastic plasmacytoid dendritic cell neoplasm; clonal hematopoiesis; myelodysplastic syndrome.