Granulocytic Sarcoma Preceding Acute Myeloid Leukaemia

The clinical and histopathological features of 3 cases of colourless granulocytic sarcoma preceding acute myelogenous leukaemia by 3, 12, and 18 months are presented. One patient had involvement of the jejunum, another patient had involvement of the vulva and cervix, the third patient had a bone tumour. In 2 patients a misdiagnosis of non‐Hodgkin's lymphoma of the histiocytic type was made, in 1 patient the initial diagnosis was eosinophilic granuloma. The diagnosis of granulocytic sarcoma depends upon the demonstration of granulocytic differentiation in the tumour. This should imply the use of naphthol AS‐D chloroacetate stain;touch imprints and electron microscopy. The differential diagnosis of granulocytic sarcoma and histiocytic lymphoma is discussed. The pertinent literature is reviewed.