Sweet's syndrome and malignancy in the U.K.

Acute febrile neutrophilic dermatosis (Sweet's syndrome) is reported to be a marker for underlying malignancy. Much of the evidence for this is based on case reports, small series of cases and reviews of the literature. In order to clarify the association with malignancy and determine the common clinical features of Sweet's syndrome, we reviewed the case notes of patients presenting to six dermatology units in the U.K. Eighty-seven cases of histologically proven Sweet's syndrome were reviewed. Fourteen patients (16%) developed associated malignancy, predominantly haematological, two patients (2%) had a history of previous malignancy and four patients (5%) had premalignant conditions (monoclonal gammopathy, two: myelodysplasia, two). Malignancy developed up to a year after presentation with Sweet's syndrome. Patients with associated malignancy were more likely to be anaemic (P < 0.01) at presentation, had a lower mean platelet count (207 x 10(9)/L vs. 332 x 10(9)/L; P < 0.003) and were, on average, older (59 years vs. 49 years; P = 0.002). Contrary to previous reports, a greater percentage of females developed malignancy than males.