GATA3 Is Underexpressed in Penile Neoplasia

Penile squamous cell carcinoma (PSCC) and its established precursor, penile intraepithelial neoplasia (PeIN), are classified as HPV-associated and HPV-independent. However, there is a spectrum of precursor lesions, which presents diagnostic challenges due to morphologic overlap. Immunohistochemical loss of GATA3, a tumor suppressor gene, has recently been reported in vulvar neoplasia. In this study, we evaluate the expression and diagnostic utility of GATA3 immunohistochemistry (IHC) in penile neoplasia. GATA3, p53, and p16 IHC was performed on 97 penile lesions, including lichen sclerosus (LS, N=14), condyloma acuminatum (N=11), squamous hyperplasia (SH, N=9), verrucous lesions (N=3), HPV-independent (N=12) and HPV-associated (N=18) PeIN, invasive HPV-independent, (N=19) and HPV-associated (N=11) PSCC, and normal skin (NL, N=41). GATA3 expression was scored as >75% basal/parabasal staining (pattern 0), 25% to 75% (pattern 1), 5% to 25% (pattern 2), and