Utility of p53 and p16 immunohistochemistry in the diagnosis of human papillomavirus‐associated oral epithelial dysplasia: a retrospective study of 105 patients

• DOI: 10.1111/his.15413
• Publication Date: 2025-02-05T02:18:36Z
• Authors: Damir Rosic; Zia A Khan; Linda Jackson‐Boe...; Mark R Darling; Erin Chapman; Lawrence Lee; Kelly Yi Ping Liu; Tony L Ng; Yen Chen Kevin Ko; Christina McCord
• Keywords: Malignant Transformation; Epithelial dysplasia; Carcinoma in situ

Aims This study investigated the utility of combined p16 and p53 immunohistochemistry (IHC) for diagnosing high‐risk human papillomavirus (HR HPV)‐associated oral epithelial dysplasia (OED) its associated clinical behaviour, including disease recurrence transformation to malignancy. Methods Results The expression was evaluated in 105 cases HR HPV‐positive cavity OED, which 104 were scored as positive p16. HPV status confirmed by reverse transcriptase quantitative polymerase chain reaction (RT‐qPCR) E6 mRNA or RNA situ hybridization (ISH). Seven p16‐positive OED with abnormal and/or TP53 mutation negative ISH excluded. Most (93%) demonstrated classic HPV‐associated basaloid morphology, 7% keratinizing. most affected sites floor mouth/ventral tongue (61%), followed lateral (18%) gingiva (13%). IHC showed that 76% a null‐like / basal‐sparing pattern, while 24% mid‐epithelial/basal sparing pattern. Ten exhibited an invasive suspicious microinvasive component on biopsy. Dysplasia recurred 14 cases, single case transformed squamous cell carcinoma. Conclusion combination positivity pattern is predictive eliminating need further HPV‐specific testing. Although may co‐occur carcinoma biopsy, malignancy low.