Role of Magnification in Visual Evaluation of Manual and Automated HPV In-Situ Hybridization in Cell Blocks (CB) from Metastatic Oropharyngeal Carcinoma
Momin T Siddiqui, Cynthia Cohen, Nazneen Fatima. Emory University Hospital, Atlanta, GA
Background: Determination of Human papillomavirus (HPV) status has strong diagnostic, prognostic, and therapeutic implications in oropharyngeal cancers (OC). Determining the integration status of HPV by in situ hybridization (ISH) is cost effective and routinely utilized in clinical practice. However, the reliability of reporting is dependent on individual expertise and visual evaluation. In this study, we have compared the role of magnification in interpreting HPV ISH results of manual versus an automated method, using the Dako and the Enzo probe respectively.
Design: We evaluated 41 CB from fine needle aspiration of metastatic OC to neck lymph nodes. We performed manual HPV ISH with the Dako probe, and Leica Bond-III automation using the Enzo probe. Punctate dot-like nuclear positivity observed with low, intermediate or high magnifications, 10 x, 20 x or 40-60x, was assigned as 3+, 2+ and 1+ respectively. A single cell showing nuclear punctate dot-like staining was considered a positive result.
Results: Two of 41 CB (4%) with manual HPV ISH and 12 of 41 CB (29%) with the automated method positive at 10x magnification, were considered 3+. Fourteen of 41 CB (34%) with manual HPV ISH and 3 of 41 CB (7%) with automation positive at 20x magnification, were 2+. Nine of 41 CB (21%) with manual HPV ISH and 15 of 41 CB (36%) with automation positive at 40-60x magnification, were considered 1+.
|HPV ISH (Positive)||10X (3+)||20X (2+)||40-60X (1+)|
|Manual||2/41 (4%)||14/41 (34%)||9/41 (21%)|
|Automated||12/41 (29%)||3/41 (7%)||15/41 (36%)|