Blastic Plasmacytoid Dendritic Cell Neoplasm: Analysis of Clinicopathological Feature and Treatment Outcome of Seven Cases

ABSTRACT

BACKGROUND: Blastic plasmacytoid dendritic cell neoplasm (BPDCN), which is derived from the precursor of plasmacytoid dendritic cells, is a rare and highly aggressive hematologic malignancy. It has only recently been recognized as a distinct entity. BPDCN characteristically has a predilection for cutaneous involvement. OBJECTIVE: The aim of this study was to describe the clinical and pathological features of BPDCN, and to review the treatment courses to analyze the prognosis and the optimal therapeutic approach. METHODS: We retrospectively reviewed seven BPDCN cases registered in the Samsung Medical Center database between January 2010 and December 2014. RESULTS: The median age of the patients was 52 years (range, 18~79 years), and six patients were male. The clinical staging was as follows: skin (n=5), lymph node (n=6), bone marrow (n=4), and peripheral blood (n=2). The skin manifestations were bruise-like tumefaction (n=4), erythematous nodule (n=4), or multiple erythematous papules (n=1). The pathological evaluation revealed dense diffuse or nodular infiltration of neoplastic cells, which were positive for CD4, CD56, and CD123 in the immunohistochemical analysis. Six patients received multiagent chemotherapy as the first-line treatment, alone (n=4), or followed by stem cell transplantation (SCT, n=1) or concurrent radiotherapy (n=1). The median progression-free survival after the first-line treatment was 6 months (range, 2~12 months). CONCLUSION: Three different skin manifestations were observed, with pathological features analogous to each other. All patients who received chemotherapy without SCT achieved partial or complete response but experienced relapse. Furthermore, they showed various clinical courses irrelevant to the cutaneous involvement.