Abstract
This review deals mainly with the essentials of hairy cell leukemia (HCL) detailing clinical aspects, laboratory findings and morphology. Rare manifestations of HCL are listed. Newer aspects relating to cytokines, soluble interleukin receptors and TNF are reviewed. Differential diagnosis including HCL-variant, SLVL, PLL and CLL/PLL are discussed. Prognostic factors and in particular therapeutic aspects are detailed with particular emphasis on the new purine analogues Pentostatin and 2-CdA. A list of suggested reading is offerred.