Hairy cell leukemia is a relatively rare but distinct B-cell lympho-proliferative disorder of the blood, bone marrow, and spleen that accounts for only 2% of all adult leukemia cases. The median age at presentation is 50-55 years, with a 4:1 male to female predominance. Although considered uncommon, a number of unusual clinical presentations have been noted in the literature, including the pres...

Low-dose interferon-a (IFN-a) therapy is consistently effective in the treatment of hairy cell leukemia (HCL). In two cases of resistance to IFN-a administration, we diagnosed variant HCL, a form of HCL with intermediate features between typical HCL and B cell prolymphocytic leukemia. We tried to distinguish variant and typical hairy cells (HCs) by Northern blot analysis of the oncogenes expres...