Study of Expression of P۱۶ in Premalignant and Malignant Lesions of Penis and Their Significance

Background & Objective: Penile squamous cell carcinoma (SCC) is an extremely rare malignancy. It is usually caused by chronic human papillomavirus (HPV) ۱۶ and HPV ۱۸ infections. This study was conducted to investigate the immunohistochemical overexpression of p۱۶, a surrogate marker for HPV, and to evaluate its usefulness as a potential diagnostic biomarker.Methods: In this cross-sectional prospective and retrospective cohort study, ۵۶ penile squamous cell carcinoma (SCC) specimens and five penile premalignant specimens were evaluated in Kasturba Medical College, Mangalore, India, from January ۲۰۱۳- December ۲۰۱۸ in terms of clinical and histopathological features. Immunohistochemical expression for p۱۶ in cases and controls was evaluated. Statistical comparison of p۱۶ expression among clinical features, histological subtype, grade, and stages of tumor were done.Results: Analysis of the pattern of p۱۶ staining showed diffuse and strong nuclear and cytoplasmic expression in ۳۲.۸% of cases. There was a highly significant association (P<۰.۰۰۱) of pattern of p۱۶ expression among the HPV and non-HPV subtypes of penile carcinoma. p۱۶ expression was not significantly associated with other prognostic parameters like the site of lesion, lymphovascular invasion, perineural invasion, histologic grade, and pathologic stage.Conclusion: The expression of p۱۶ would be a useful tool in the discrimination between the HPV-associated and non-HPV-associated subtypes of penile SCC that helps to predict the aggressiveness and invasive potential of the respective histologic subtypes.

Keywords:

P۱۶ , oncogenic HPV , Penile SCC , India , SCC , Immunohistochemical Staining