en Pathology Pathology پژوهشي Original Article <p style="text-align: justify;"><span style="font-size:14px;"><span style="font-family:Arial;"><span style="line-height:200%"><span style="unicode-bidi:embed"><b><span style="line-height:200%">Backgrounds:</span></b><span style="line-height:200%"> Kaposi sarcoma is a low-grade vascular tumor with the uniform expression of latent nuclear antigen-1 of the human herpes virus 8 (HHV-8). Differentiation of Kaposi sarcoma from other benign and malignant vascular or non-vascular spindle cell lesions is sometimes a manner of challenge. Thus, the expression of human herpes virus 8 in a fixed specimen would be diagnostically useful. This study aimed at immunohistochemical detection of human herpes virus-8 in cutaneous vascular lesions.<br> <b>Methods:</b> This cross-sectional study was conducted on 46 cases of cutaneous vascular lesions including six cases of Kaposi Sarcoma, twenty-five cases of Pyogenic Granuloma, four cases of Angiolymphoid Hyperplasia with Eosinophilia, three cases of Masson Tumor, two cases of Arteriovenous Hemangioma, two cases of Sclerosing Hemangioma, three cases of Angiofibroma, and one case of Lymphangioma. After histologic confirmation, immunohistochemistry was done on sections of paraffin-embedded tissue with mouse anti-HHV-8 antibody. </span></span></span><br> <span style="line-height:200%"><span style="unicode-bidi:embed"><b><span style="line-height:200%">Results:</span></b><span style="line-height:200%"> Of 46 patients, 27 (58.7%) were male and 19 (41.3%) were female, and the mean age was 46.36&plusmn;17.48 years. All 6 Kaposi sarcoma cases showed strong, nuclear staining for HHV-8 (100%). All 6 patients with HHV-8 positive results were older than 60 years.&nbsp; Sarcoma cases included four (66.7%) resection specimens from the soft tissues of the leg and two (33.3%) resection specimens from the soft tissues of the hand. </span></span></span><br> <span style="line-height:200%"><span style="unicode-bidi:embed"><b><span style="line-height:200%">Conclusions:</span></b><span style="line-height:200%"> The high sensitivity and specificity of the immunohistochemical method for detecting HHV-8 in skin lesions, especially Kaposi sarcoma, makes it a reliable and cost-effective tool to differentiate Kaposi sarcoma from other vascular and non-vascular spindle cell lesions.</span></span></span></span></span></p> Human Herpes Virus 8, Kaposi Sarcoma, Cutaneous vascular lesions, Immunohistochemically method. 172 177 http://ijbc.ir/browse.php?a_code=A-10-834-2&slc_lang=en&sid=1 Saeedeh Khakisahneh saeedekhaki@yahoo.com 10031947532846009554 10031947532846009554 No Students Research Committee, Kermanshah University of Medical Sciences, Kermanshah, Iran Maryam Hematti maryam_hematti@yahoo.com 10031947532846009555 10031947532846009555 No Clinical Research Development Center, Imam Reza Hospital, Kermanshah University of Medical Sciences, Kermanshah, Iran Sedigheh Khazaei skhazaei2003@yahoo.com 10031947532846009556 10031947532846009556 No Clinical Research Development Center, Imam Reza Hospital, Kermanshah University of Medical Sciences, Kermanshah, Iran Mazaher Ramezani mazaher_ramezani@yahoo.com 10031947532846009557 10031947532846009557 Yes Molecular Pathology Research Center, Imam Reza Hospital, Kermanshah University of Medical Sciences, Kermanshah, Iran