[Hairy cell leukemia: pathomorphology, cytology and cytochemistry]

In 10 cases of hairy cell leukaemia histological, cytological, cytochemical and in some of the cases immunocytological investigations were carried out. In addition to clinical, cytological and cytochemical findings arising suspicion of hairy cell leukaemia, in three cases the multifocal reaction of acid-phosphatase appeared to be tartarate sensitive (at the concentration of L+-tartaric acid--0,75%), indicating in accordance with findings of Burns et al. (9), that tartarate resistency of the acid-phosphatase reaction ("isoenzyme 5" Katayama és mtsai, 24) has no absolute diagnostic significance. Pathomorphological investigation of different tissues (spleen, lymph node, bone marrow, liver) has revealed the characteristic localization of the spleen infiltrates (cords of Billroth) and the formation of the so called pseudosinuses. These morphological findings may contribute to the diagnosis of hairy cell leukaemia.