P16 protein Expression in Nasopharyngeal Carcinoma Histologic Subtypes in Kano.

Background: Nasopharyngeal carcinoma (NPC) is the most common head and neck malignancy with the highest incidence seen in South China, Southeast Asia, Northeast India and parts of North Africa. P16 (p16INK4a), a cyclin-dependent kinase, is essential for the regulation of cell proliferation and plays a key role in the activation of the apoptotic pathway. The objective of this study is to determine the prevalence and clinicopathological associations of p16 expression in NPC subtypes in Kano. Methodology: This was a retrospective study covering five years (2015 to 2019) of all NPC cases diagnosed at the Department of Histopathology, Aminu Kano Teaching Hospital, Kano (AKTH). The collected data included patients' demographic details, clinical information, histological diagnosis, and p16 Immunohistochemical status. Results: NPC cases showed a bimodal age distribution, with a mean age of 40 years. The majority of patients were male, giving a male-to-female ratio of about 4.2:1. P16 positivity was observed in more than a third of the cases, more frequent in males than in females. Non-keratinizing nasopharyngeal carcinoma was the most common subtype and showed more p16-positivity. Conclusion: This study identifies p16 expression in a subset of nasopharyngeal carcinoma cases, with a higher frequency among males and a predominance in non-keratinizing nasopharyngeal carcinoma. These findings contribute to the understanding of p16 as a potential biomarker in NPC biology. While the prognostic implications remain uncertain, further molecular subtyping and prospective outcome studies are needed to clarify the role of p16 in risk stratification and therapeutic decision-making.