Granulocytic sarcoma

Dr Craig Hacking and Dr Jeremy Jones et al.

Granulocytic sarcoma (also called myeloid sarcoma and chloroma) is a rare neoplasm comprised of myeloid precursor cells.

It can occur in association with:


It is typically seen is in children with ~60% occurring in individuals less than 15 years of age. There is no recognised gender predilection.

Granulocytic sarcoma may develop during the course of a haematologic disorder; but is seen to precede the disorder in 35% of cases.


Granulocytic sarcoma lesions are composed of immature myeloid elements and therefore represents focal accumulation of leukaemic cells. In contrast to its associated entities, the lesion(s) take the form of a solid soft tissue mass(es).


Being extramedullary is a key feature.

Almost any tissue can be affected, with skin and bone being the commonest. They have been reported in the skull, face, orbit and paranasal sinuses. Lesions have been reported in the tonsils, oral and nasal cavities and within the lacrimal, thyroid and salivary glands. The central nervous system can also be affected.

Radiographic features

Exact imaging features will depend on the location and involved organ.

Refer to:

History and etymology

  • first described by A Burns in 1811 3
  • termed "chloroma" in 1853 by King due to typical forms have a green color from high levels of myeloperoxidase in immature cells; renamed after because at least 30% of cells didn't contain myeloperoxidase
  • renamed as granulocytic sarcoma in1966 by Rappaport due later findings that not all of the cells are green
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Article Information

rID: 10568
Section: Pathology
Synonyms or Alternate Spellings:
  • Chloroma
  • Myeloid sarcoma
  • Extramedullary myeloblastoma

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