Granulocytic sarcoma of the pancreas: a report of two cases and literature review.

Granulocytic sarcomas (GS) are extramedullary tumour masses of immature myeloid cells, also known as chloroma and extramedullary myeloid cell tumour. These neoplasms usually occur simultaneously with, or follow the onset of acute myeloid leukaemia (AML). Rarely, they are the first manifestation of AML. GS may also be the first sign of transformation to AML in patients with chronic myeloproliferative disorders and myelodysplastic syndromes. GS have been reported to occur in a variety of tissues, but presentation as an abdominal mass and, in particular, infiltration of the pancreas is rare. We report two cases of pancreatic GS, review the literature, and discuss recent insights into the basic biological properties of these rare tumours.