Clinical findings:
A 67-year-old man was referred by a dermatologist.
The patient was initially referred to a dermatologist by her PCP for progressive, persistent skin nodules that she first noticed 3 weeks earlier.
Initial clinical workup and diagnosis:
ROS: Fatigue, 5 kg weight loss in 3 months
PMH: Sinusitis.No major complications
PE: Multiple purpuric nodules (up to 5 cm) visible on arms, legs, and torso.Palpable lymphadenopathy, no hepatosplenomegaly
ECOG PS =1
Labs: WBC 14.1 x 103/uL, Hb 8.9 g/dL, platelets 54 x 103/uL. Differential analysis revealed 12% blasts, 32% neutrophils, 16% monocytes, and 40% lymphocytes.
Skin: Purpuric nodules
Peripheral blood smear: Blast cells with large, round or slightly irregular nuclei.The blastoplasm is stained gray-blue, with no granules or Auer rods present.
Bone marrow biopsy showed morphologically 40% blasts. 80% cellular marrow with interstitial infiltration.
IHC of tumor cells: CD123, CD4, CD56, TCL1 positive
Flow cytometry:
CD4, CD56, and CD123 were positive.
CD34 and T cell and B cell lineage specific markers were negative
Cytogenetics: 46 XY
Lumbar puncture showed no CNS involvement
The patient was finally diagnosed with BPDCN based on clinical and histopathological findings.
Initial treatment:
Tagraxofusp has started:
The initial dose is 12 mcg/kg according to the package label for frontline therapy, achieving CR after one cycle of treatment.