Abstract
This study reports a case of promyelocytic sarcoma that developed as a solitary sternal mass without any clinical evidence of acute promyelocytic leukemia. The case presented the diagnostic difficulties common to all aleukemic granulocytic sarcomas, and diagnosis was made possible by local identification of the PML/RARα fusion gene by fluorescent in situ hybridization. The patient was treated by surgery followed by chemotherapy plus all-trans retinoic acid therapy and local radiotherapy.