Malignancy-associated Sweet's syndrome: review of the world literature.

Sweet's syndrome is an acute febrile neutrophilic dermatosis in which approximately 20% of the reported patients have an associated cancer. We review the 79 patients with malignancy-associated Sweet's syndrome documented in the world literature. The most common underlying neoplasm was acute myelogenous leukemia (AML). Lymphomas, chronic leukemias, myelomas, myelodysplastic syndromes, and a variety of solid tumors have also been observed. The onset of Sweet's syndrome either preceded or coincided with the discovery of a previously undiagnosed cancer in greater than 60% of malignancy-associated Sweet's syndrome patients. In contrast to patients with the idiopathic form of the disease, those with a malignancy often presented with more severe cutaneous lesions, cytopenias, and/or immature cells in the peripheral blood. Extracutaneous sites of involvement included the eyes, muscles and joints, kidneys, lungs, and liver. All the manifestations of Sweet's syndrome improved dramatically with corticosteroid therapy, regardless of the response of the associated neoplasm to tumor-directed therapy.