Primary cytodiagnosis of peritoneal extramedullary hematopoiesis

Abstract

Cytologic examination of peritoneal fluid in a patient with known myelofibrosis and previous splenectomy revealed megakaryocytes along with erythroid and myeloid precursors. These findings were consistent with extramedullary hematopoietic (EMH) implants of the peritoneum. A few similar cases have been occasionally reported in the literature. This case represents an additional example of a primary diagnosis of peritoneal EMH in which therapy was based on the cytologic findings and sequential cytologic observations were made.

Extramedullary Hematopoietic Effusions

“…31 There are reports also of EMH in effusions associated with hematologic disorders. 2,6,12,30 Silverman 28 proposed the term extramedullary hematopoietic effusion to describe the presence of extramedullary hematopoietic foci on serosal surfaces.…”

“…16 Some cases have been diagnosed by fine needle aspiration with or without radiologic guidance. 20,25,27,34,35 EMH can be diagnosed in effusions when the nodules of the serous cavities seed their lining cells, which are recovered by paracentesis; this finding is usually related also to myelofibrosis, 3,7,10,11,13,14,22,23,28,31,33,36 leukemia 6,12 and congenital heart disease. 18 EMH in effusions is diagnosed by the presence of immature red and white blood cells; less often, elements of the three types can be found.…”

“…18 EMH in effusions is diagnosed by the presence of immature red and white blood cells; less often, elements of the three types can be found. 6,10,31,36 …”

Pseudo-Gaucher cells in peritoneal fluid: An uncommon manifestation of extramedullary hematopoiesis

“…6 Manifestations of EMH in serous fluids stemming from involvement of solid organs, such as liver or pleura/ peritoneum, have been previously described. [7][8][9] The presence of numerous erythroid and myeloid precursors is a typical feature. The diagnostic utility of the presence of megakaryocytes with multiple or polylobate nuclei has been cited.…”

“…The diagnostic utility of the presence of megakaryocytes with multiple or polylobate nuclei has been cited. 7 Megakaryocytes with hyperchromatic nuclei and marked nuclear membrane irregularity may be subject to misinterpretation as atypical or malignant cells. The occurrence of blast forms in extramedullary hematopoiesis may lead to difficulty in distinguishing this entity from granulocytic sarcoma and lymphoma.…”