54-year-old male was diagnosed with chronic myelogenous leukemia in peripheral blood smears and bone marrow biopsy 3 years prior. Blast phase ensued; death was due to pneumonia (specimen from autopsy).
- The lobular architecture of the hepatic parenchyma is maintained.
- Sinusoids and portal areas contain accumulations of myeloid cells in different states of maturation.
- In addition, centrilobular necrosis is noted.
Clinical findings: In the chronic phase of the disease, patients may present with weight loss, fatigue, night sweats, anemia and splenomegaly. Upon transformation, patients develop severe symptoms secondary to extensive medullary and extra-medullary leukemic cell infiltration (opportunistic infections, severe anemia, petechial bleedings due to thrombocytopenia, hepato- and splenomegaly).
Genetics: In 90-95% of cases the characteristic t(9;22) (q34;q11) translocation is observed, which fuses the BCR gene on chromosome 22 to the ABL gene on chromosome 9. This cytogenetic abnormality leads to formation of the characteristic Philadelphia (Ph) chromosome.
Cytochemistry: In contrast to other myeloproliferative disorders, neutrophils exhibit markedly decreased myeloperoxidase levels during the chronic phase of CML. In blast phase, blasts may exhibit strong to absent expression of myeloperoxisase.