Hairy cell leukemia is a rare lymphoid neoplasia. The diagnosis remains difficult given the infrequency of the pathology and the similarity with other disease, it liesmainly on the observation of hairy cells in peripheral blood and bone marrow in addition toimmunophenotyping via flow cytometry that highlights the co-expression of numerous markers.
Despite advances in diagnosis and treatment, it’s still an area that needs great development. In this case report, we describe the clinicopathologic, biologic and immunophenotypic aspects of threepatients diagnosed with hairy cell leukemiawithin a three years period (2015-2017) at CHU Hassan II, Fès, Morocco.