Hepatic involvement in hairy cell leukemia: diagnosis by tartrate-resistant acid phosphatase enzyme histochemistry on formalin fixed and paraffin-embedded liver biopsy specimens.

The leukemic infiltrate in the liver in hairy cell leukemia may be easily overlooked in conventional histological slides and an exact classification may not always be possible. In order to facilitate the identification of tricholeukocytes , it is suggested to perform the tartrate-resistant acid phosphatase stain on routinely formalin fixed and paraffin-embedded liver biopsy specimens. Thereby it will be in most cases possible to demonstrate sufficiently enough enzyme activity to establish unequivocally the diagnosis of hairy cell leukemia.