Figure 1- Peripheral blood film with a classic hairy cell morphology. The abundant pale blue cytoplasm is organized into hairy projections.
(Please note this picture is from a separate case of HCL)
Bone marrow aspirate
Figure 2- The bone marrow aspirate is packed with atypical lymphoid cell with pale blue cytoplasm, bland nuclei and an inconspicuous nucleolus.
Bone core biopsy
Figure 3 - The bone core biopsy morphology of HCL, shows atypical lymphoid cells with clearing of cytoplasm due to hairy projection (chicken wire or fried-egg appearance). IHC is typically positive for CD20, Annexin A1 and BCL1.
Figure 4 - The flow cytometric analysis shows atypical B lymphoid cells brightly positive for CD19 and CD20, which are predominantly lambda restricted (clonal B cells). The neoplastic cells express CD103, CD200 and CD25. The tumor cells are negative for CD19 and CD123 (usually HCL expresses positive CD123).