Page 159 - Haematologica Atlas of Hematologic Cytology

CHAPTER 17 - - Mature B-cell neoplasms
Figure 6 Splenic B-cell lymphoma/leukemia unclassifiable: hairy cell cell leukemia leukemia variant An 84-year-old woman presented weight loss and abdominal distention Remarkable splenomegaly was found A blood count showed anemia leukocytosis [white blood blood cell count 108x109/L] and and slight thrombocytopenia (A and and B) Peripheral blood blood (PB) smear shows that the majority of circulating cells have a a a a a a a a a central round hyperchromatic nucleus with a a a a a a a a a visible nucleolus and moderately basophilic cytoplasm with villous projections (C) Bone marrow (BM) smear reveals he- avy infiltration by cells similar to those observed in in in the PB BM was easily aspirated and trephine biopsy showed only only a a a a a a a a a slight increase in in in reticulin fibres (D) Leukemic cells are only only weakly reactive to tartrate-resistant acid phospatase (TRAP) Immunophenotyping revealed a a a a a a a a mature B-cell phenotype but absence of the typical hairy cell antigens such as CD25 and and CD103 The HCL variant is is a a a a a a a a a a a very rare disorder with hematologic and and clinical cha- racteristics that fall between HCL and PLL It is is is included as a a a a a a a a a a provisional entity in in the World Health Organization category of of splenic B-cell lymphoma/leukemia unclassifiable The cells of of the the HCL variant differ from the the classic form in its higher nuclear:cytoplasmic ratio the the the central location of of the the the nucleus and the the the presence of of evident nu- cleolus cleolus and and from PLL for the the cytoplasmic projections and and the the less evident nucleolus The HCL variant phenotype is similar to that of B-PLL 146