Dysplastic Lesions of the Gingiva: Prevalence and Risk Factors Including Human Papillomavirus (HPV) Infection

Abstract

<h3>Background</h3> Verrucous gingival lesions are common within the spectrum of proliferative verrucous leukoplakia (PVL), and the gingiva is not an unusual location for oral carcinoma. However, non-PVL associated dysplastic gingival lesions appear to be less common and may not progress directly to malignancy. In addition, it appears HPV likely plays a limited etiologic role in any form of dysplasia of the gingiva. <h3>Materials and Methods</h3> Following IRB approval, all "dysplasia" cases between 2009-2019 were identified from the archives of the University of Florida Oral Pathology Biopsy Service. Exclusion criteria included verrucous lesions, lesions from multiple sites compatible with PVL, and cases diagnosed as mild atypia/dysplasia. The remaining gingival dysplasia cases were evaluated for age, gender, contributory history, clinical appearance/impression, symptoms, duration, and p16INK4a immunohistochemistry (IHC) results. <h3>Results</h3> A total of 72 biopsies were included in our database from 54 patients. The mean age was 70.3 years (range of 27 - 90), with a female: male ratio of 1.4:1. 69.4% (n=50) were located on the posterior gingiva and 62.5% (n=45) the mandibular gingiva. Reported contributing histories included smoking (n=9, 12.5%), previous oral dysplasia (n=9, 12.5%), or oral cavity malignancy (n=24, 33.3%). The two most common clinical impressions were leukoplakia (n=16, 16.7%) and carcinoma (n=18, 25%). Twenty-five of the 72 cases (34.7%) were symptomatic with pain, swelling and/or bleeding. The most recent biopsy from 32 of the patients was low-grade dysplasia, 34 had high-grade dysplasia, and 6 koilocytic dysplasia. Only 4 of 6 koilocytic dysplasia cases were positive for p16, with no low-grade or high-grade lesions demonstrating positivity. <h3>Conclusion</h3> This study confirms that p16 expression is rarely present in dysplastic lesions of the gingiva, unless koilocytic dysplasia is also present.