Myelosarkom der Leber
Hepatic myeloid sarcomas, also referred to as hepatic granulocytic sarcoma or hepatic chloromas, are rare neoplasms comprised of myeloid precursor cells happening in the liver. They are a unique presentation of acute myeloid leukemia (AML).
Please refer to the main article on myeloid sarcoma/chloroma for a broad discussion on this entity.
Epidemiology
Myeloid sarcomas occur in 3-5% of patients with acute myelogenous leukemia (AML). They are also associated with chronic myeloid leukemia (CML) and myelodysplastic syndromes .
More common locations for myeloid sarcoma are bones, lymph nodes, soft tissues, skin and breasts, with the liver involved less commonly (4% in one study) .
Clinical presentation
May present during remission or relapse of the underlying disease (occurs during remission in 20%) .
Pathology
Consists of myeloid blasts or precursor cells. It sometimes stains green with the application of myeloperoxidase, hence the older term "chloroma" ("chloros" is the Greek word for "green").
Radiographic features
Imaging features mimic hepatic lymphoma. A presumptive diagnosis of hepatic myeloid sarcoma is made in the setting of a patient with known AML.
CT and MRI
- more ill-defined margins than hepatic lymphoma
- more heterogeneous enhancement than hepatic lymphoma
- may result in biliary obstruction
Nuclear medicine
- FDG-PET: highly sensitive for detection
Treatment and prognosis
Myeloid sarcoma is predictive of a poor outcome for a patient's AML.
Hepatic myeloid sarcoma is treated with chemotherapy or targeted radiotherapy .
Differential diagnosis
- graft-vs-host disease (GvHD): more common
- nodular regenerative hyperplasia
- post-transplant lymphoproliferative disorder (PTLD)
- extramedullary hematopoiesis
- infection / hepatic abscess