Cavernous hemangioma-like Kaposi sarcoma: a unique histopathologic variant

Area of Science:

• Oncology
• Pathology
• Virology

Background:

• Kaposi sarcoma (KS) is a complex angiolymphatic neoplasm with diverse clinical presentations.
• Established classifications include 4 distinct KS types and 3 histologic stages.
• Unique histopathologic variants of KS are infrequently documented.

Observation:

• The authors present a case of KS with an unusual histopathologic appearance.
• The lesion microscopically resembled a cavernous hemangioma.
• Diagnostic confirmation involved specific immunohistochemical markers.

Findings:

• Human herpesvirus type 8 (HHV-8) staining was positive, a key indicator for KS.
• D2-40 staining, typically used for lymphatic endothelium, also aided in characterization.
• The combined findings confirmed the diagnosis of Kaposi sarcoma despite its hemangioma-like morphology.

Implications:

• This case highlights the importance of considering KS in the differential diagnosis of vascular tumors.
• Advanced diagnostic techniques like HHV-8 and D2-40 staining are crucial for accurate KS identification.
• Understanding rare histopathologic variants expands diagnostic capabilities in oncology and pathology.