Background: In patients with malignancy-associated Sweet syndrome, a thorough evaluation for leukemia cutis should be considered.
Objective: We sought to describe the clinicopathologic characteristics of histiocytoid Sweet syndrome.
Methods: We retrospectively identified patients with histiocytoid Sweet syndrome at our institution from January 1992 through December 2010. We evaluated the underlying cutaneous infiltrate using immunohistochemistry and fluorescence in situ hybridization.
Results: We re-evaluated all 22 patients with hematologic malignancy-associated Sweet syndrome. Six patients had a monocytoid infiltrate that was consistent with histiocytoid Sweet syndrome; subsequent evaluation of these patients demonstrated cytogenetic abnormalities on prior bone-marrow biopsy specimens. Fluorescence in situ hybridization analysis was feasible in cutaneous specimens from 5 of the 6 patients and demonstrated the same cytogenetic abnormalities that were identified on prior bone-marrow biopsy specimens in 4 patients. Therefore, these 4 patients may have had a form of leukemia cutis.
Limitations: This was a retrospective study.
Conclusion: For patients with histiocytoid Sweet syndrome, an underlying hematologic malignancy, and a monocytoid infiltrate on biopsy specimen, fluorescence in situ hybridization of the cutaneous infiltrate may be beneficial to identify cytogenetic abnormalities that may indicate leukemia cutis.
Keywords: Sweet syndrome; cytogenetic abnormalities; fluorescence in situ hybridization analysis; histiocytoid Sweet syndrome; leukemia cutis; malignancy-associated Sweet syndrome.
Copyright © 2014 American Academy of Dermatology, Inc. Published by Mosby, Inc. All rights reserved.