Morphologic and immunophenotypic evidence of in-situ Kaposi's sarcoma

Abstract

Background: The spectrum of Kaposi's sarcoma (KS) has been expanded to include pre-KS lesions. Case Presentation: We report, for the first time, a case providing direct histological evidence of the development of early (in-situ) KS from mediastinal lymphatic vessels in the setting of chronic lymphedema in an HIV-positive patient. Spindle-shaped and endothelial cells in these early KS-appearing lesions were immunoreactive for HHV8, D2-40 and CD34. Conclusion: Our findings suggest that HHV8-infected spindle-shaped cells associated with lymphangiogenesis that evolve into KS lesions, acquire from the outset an aberrant mixed vascular and lymphatic endothelial cell phenotype. © 2006 Konstantinopoulos et al; licensee BioMed Central Ltd.