Multiple granulocytic tumors of the skin: report of six cases of myelogenous leukemia with initial manifestations in the skin.

The clinical and pathologic findings in six patients with myelogenous leukemia presenting initially as multiple granulocytic tumors of the skin were reviewed. The skin of the trunk was most commonly involved with multiple, confluent erythematous plaques and soft, tender, non-ulcerated, violaceous nodules. Two patients had been treated for malignant lymphoma eight and nine years prior to the onset of skin lesions (Hodgkin's disease and nodular lymphocytic lymphoma, respectively), and cutaneous granulocytic leukemia developed in sites of irradiated skin. The skin biopsies in all cases were originally misinterpreted by the pathologist as malignant lymphoma and the correct diagnosis of granulocytic leukemia was not established in any of the cases until overt extracutaneous involvement was detected. The interval in the six patients from skin biopsy to definite involvement of blood and bone marrow by acute granulocytic leukemia ranged from three weeks to six months with a mean interval of 3.8 months. The mean duration of survival from the diagnosis of extracutaneous dissemination was 12.7 months (range of three months to two and one-half years). Poorly differentiated myelogenous leukemia was demonstrated at postmortem examination in all cases. Cytochemical stains of formalin-fixed, paraffin-embedded tissues confirmed the granulocytic origin of the neoplasm: leukemic cells in skin biopsies, bone marrow aspirates, and autopsy specimens contained abundant naphthol AS-D chloracetate esterase. The findings indicate that granulocytic leukemia may rarely present with skin tumors as the original manifestation of the disease. Recognition of the distinctive clinical, histopathologic, and enzyme histochemical features of the lesion provide a basis for distinguishing granulocytic sarcoma of the skin from mycosis fungoides and other cutaneous malignant lymphomas.