ORAL HIV-ASSOCIATED KAPOSI SARCOMA: A COMPARISON BETWEEN IMMUNOHISTOCHEMISTRY AND qPCR TECHNIQUES FOR DETECTION OF HHV8

Abstract

Objective: To compare the diagnostic accuracy of immunohistochemistry compared to real-time PCR (using a simple phenol-chloroform DNA extraction protocol) in the detection of HHV8 in small oral biopsies of Kaposi sarcoma. Also to validate the use of this DNA extraction protocol to extract HHV8 DNA.Material and methods: Seventeen cases of oral KS were examined. Data including gender, age, and anatomic location were obtained from patient´s records and histological sections stained with hematoxylin and eosin (H&E) were reviewed. Immunohistochemistry was used to detect HHV8 in lesions of interest, as well as real-time PCR.Results: All the patients were HIV positive, the mean age was 35.5 years old, and the affected oral sites were palate (47%), gingiva (29.4%), tongue (11.8%), lip (5.9%), and oral floor (5.9%). Fifteen samples showed positive staining for HHV8 and only two samples were negative. The same results were observed using real-time PCR HHV8-DNA detection.Relevance: Our findings suggest that immunohistochemistry is faster and cheaper to perform than real-time PCR and was shown to have similar levels of sensitivity and accuracy for detection of HHV8 even in small biopsies. Additionally DNA extraction using a non-commercial kit, as done in this study can further reduce the costs to a pathology service.