A 55-year-old woman who underwent radical mastectomy with axillary lymph node dissection 8 years ago now has progressive woody swelling of the ipsilateral arm. Recently a violaceous nodule appeared on the affected limb and biopsy shows malignant endothelial cells forming vascular channels. What is the diagnosis?

• A Kaposi sarcoma
• B Malignant melanoma
• C Angiosarcoma arising de novo
• D Stewart-Treves syndrome ✓

Explanation

Stewart-Treves syndrome is lymphangiosarcoma arising in a chronically lymphoedematous limb, classically many years after radical mastectomy with axillary clearance. The long-standing post-surgical lymphoedema is the predisposing factor, distinguishing it from Kaposi sarcoma, which is associated with human herpesvirus 8 and immunosuppression. De novo angiosarcoma lacks the preceding lymphoedematous field change, and melanoma would show junctional activity and melanocytic markers rather than malignant endothelial channels.

Reference: Robbins and Cotran Pathologic Basis of Disease, 10th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.