Granulocytic sarcomas (so-called chloromas) are rare extramedullary tumorlike proliferates of myelogenous precursor cells that may de novo precede acute leukemia or coincide with the first manifestation or relapse of acute myeloid leukemia. Rarely, such tumors represent the initial manifestation of a blast crisis in the course of a chronic myeloproliferative disease, such as chronic myeloid leukemia. If they occur in aleukemic patients incorrect diagnoses may result. Differential diagnostic considerations are being discussed by presenting the case of a 58-year-old man who experienced spinal cord compression by an isolated epidural mass lesion.