Expression of the caveolins in dermal vascular tumors

Introduction: Histopathologic criteria are usually sufficient for the accur ate distinction of benign from malignant dermal vascular tumors. A minority of cases, however, pose a vexing diagnostic dilemma. Recent studies sugges t that caveolin, a scaffolding cell membrane protein, may prove helpful in predicting the biologic behavior of endothelial-derived neoplasms. Methods: We analyzed a series of 30 dermal vascular tumors including 12 lob ular capillary hemangiomas (LCH), 4 cases of targetoid hemosiderotic hemang iomas (TH), 4 cases of tufted angioma (TA), 12 cases of Kaposi's sarcoma (K S), 4 epithelioid (EH) and 1 spindle cell hemangioendothelioma (SH), and 4 cases of angiosarcoma (AS). The distribution of immunoreactivity was analyz ed by quantifying cell membrane staining in each case. Results: There was a statistically significant difference in the expression of caveolin between LCH (mean labeling index=91.6), TH (mean labeling inde x=89.7), and TA (mean labeling index=87.2) and the cases of KS (mean labeli ng index=21.6, EH mean labeling index 23.1), and the AS ( mean labeling ind ex=6.3). Conclusions: These results indicate that antibodies to caveolin may be usef ul in separating benign and malignant dermal vascular tumors and possibly i mplicates this peptide in their pathogenesis.