Acute myelofibrosis in megakaryoblastic leukemia with translocation between chromosomes 8 and 14.

In a 45-year-old woman with severe normochromic anemia (Hb 2.8 g%) an extensive myelofibrosis and infiltration of the bone marrow with small blasts was observed histologically. Cytochemical examination of the blasts showed a negative peroxidase and a strongly positive alpha-NE reaction. PAS reaction was slightly granular positive in the cytoplasmic protuberances of the blasts and in the platelets. Marker analysis yielded no evidence of lymphatic origin of the blasts. In flow-cytometric studies of 230,000 cells a homogeneous 2c blast population could be identified. Cytogenetic analysis revealed an abnormal pseudo-diploid karyotype characterized by 2 acrocentric marker chromosomes caused by a translocation of chromosomes 8 and 14, as usually seen in Burkitt type lymphoma. Finally the reaction product of platelet-specific peroxidase could be demonstrated in the perinuclear cisternae of the endoplasmic reticulum by electron microscopy. Highly elevated beta-thromboglobulin and platelet factor 4 plasma levels were also measured. Following an ineffective treatment with daunoblastine and ARA-C, the patient died of pseudomonas aeruginosa septicemia after having received high-dose ARA-C treatment.