IS Case 258: Bilateral breast chloroma

Sam McCabe, MD

Imaging Sciences URMC 2009
Publication Date: 2009-06-26


A 50-year-old female with history of acute myeloid leukemia (AML) now presents with bilateral palpable breast abnormalities for the past month.


Bilateral CC mammogram demonstrate bilateral irregular masses without calcifications which correspond to the sites of palpable abnormality. Ultrasound (US) of the bilateral palpable breast abnormalities demonstrates bilateral large, solid heterogeneous masses. Doppler interrogation (not shown) demonstrated internal vascularity on both masses.


Chloroma, also known as extramedullary myeloblastoma or granulocytic sarcoma, is the name given to an extramedullary solid tumor associated with myelogenous leukemia. They are solid tumors composed of immature granulocyte precursor cells. Chloromas are uncommon manifestations of leukemia and rarely involve the breast. The term "chloroma" is derived from the Greek "chloros" meaning "green" - the tumors often have a green tint on gross inspection.

Chloromas may rarely occur during the disease course of chronic myelogenous leukemia (CML) or other myeloproliferative disorders including myelodysplastic syndrome, polycythemia vera, essential thrombocytosis and myelofibrosis. The presence of a chloroma signals transformation of these pre-malignant conditions into AML. Chloromas may also develop as the lone manifestation of disease recurrence after successful treatment of AML. This heralds imminent systemic relapse, typically within less than one year [2]. Very rarely, a so called "primary chloroma" may occur, in which there is no history of previous myelogenous disease. In almost all reported cases, leukemia develops within a year [3].

Chloromas may occur in any tissue, but they are most commonly seen in the skin and gums. Other common locations include lymph nodes, small bowel, mediastinum, epidural space, uterus, and ovaries. Mammographically, breast chloromas are noncalcified, irregular masses with poorly defined "feathery" margins. Ultrasound typically shows a large malignant appearing mass with spiculations, angular margins, and hypoechoic areas.

Treatment is anti-leukemic chemotherapy.


  1. Barloon TJ, Young DC, Bass SH. Multicentric granulocytic sarcoma (chloroma) of the breast: mammographic findings. AJR Am J Roentgenol. 1993 Nov;161(5):963-4. PMID: 8273636 [PMID: 8273636]
  2. Byrd JC, Weiss RB. Recurrent granulocytic sarcoma. An unusual variation of acute myelogenous leukemia associated with 8;21 chromosomal translocation and blast expression of the neural cell adhesion molecule. Cancer. 1994 Apr 15;73(8):2107-12. PMID: 7512442 [PMID: 7512442]
  3. Byrd JC, Edenfield WJ, Shields DJ, Dawson NA. Extramedullary myeloid cell tumors in acute nonlymphocytic leukemia: a clinical review. J Clin Oncol. 1995 Jul;13(7):1800-16. PMID: 7602369 [PMID: 7602369]

4 images