Rare Report Case of Oral Verruca Vulgaris on Torus Palatinus

Abstract Verruca vulgaris, also known as common warts, is most often seen on the skin of hands and feet. Human papilloma virus (HPV) plays an aetiological role in the development of this lesion. Oral verruca vulgaris (OVV) may occur on the palate, buccal mucosa, and tongue. Although asymptomatic and benign, HPV has been linked to squamous cell carcinoma in the oral cavity and oropharyngeal areas. Therefore, prompt surgical removal of OVV is warranted. We report a case of a OVV in a 48-year-old male patient on palate. The lesion was a white nonscrapable lesion in the middle of a torus palatinus. Excisional biopsy was done together with surgical removal of torus palatinus. Histopathological analysis confirmed the diagnosis of OVV.


Introduction Oral Verruca Vulgaris
Verruca vulgaris is typically seen on hands, feet, toes, and fingers. 1 The occurrence of verruca vulgaris intraorally is less common compared to oral squamous papilloma. 2 Although OVV rarely shows malignant change, it could be transmitted to other sites if left untreated. 3 The mode of transmission of the human papilloma virus (HPV) could be from autoinoculation, oral sex, or vertically from pregnant mother to child. 4,5,6

Torus Palatinus
Torus palatinus is the bone prominence or the exostosis situated in the median palatine region of the maxilla; it has a high prevalence in Asian and Mongoloid ethnic groups. 7 The lack of vascularity and thin mucosal covering of the tori increases the likelihood of traumatic ulcers and inflammation around the exostosis. 8 The surgical removal of torus palatinus is usually indicated before fitting maxillary dentures or when there is a traumatic ulcer. In some severe instances, ulcers may expose the torus by perforating the mucosa causing dysphagia and halitosis. 9

Case Report
A 48-year-old male patient complained of a whitish growth on his palate. He noticed the lesion approximately 2 months before seeking advice from his dentist. The patient was a smoker averaging 10 cigarettes per day, with occasional alcohol intake. Intraoral examination revealed a whitish lesion confined to the middle of a torus palatinus. The lesion was asymptomatic and was not tender on palpation (►Fig. 1).

Keywords
Oral Verruca Vulgaris on Torus Palatinus Khoo et al.

Surgical Procedure
An excisional biopsy was done concomitant with torectomy. The surgical wound was sutured without the use of a splint. Overall 14 days after surgery, the site had healed uneventfully. A follow-up at 6 months revealed no recurrence (►Fig. 2). The soft tissue sends to the pathological department for biopsy report.

Biopsy Result
►Fig. 3A and 3B showed under the microscope; acanthosis is seen with marked hyperkeratosis with bacterial colonies on the surface. Hypergranulosis is seen with coarse keratohyalin granules. Koilocytic change and intracellular bodies are seen. These findings are suggestive of OVV.

Discussion
The palatal torus is quite common in Southeast Asia; the removal of it is done to help fit dentures that cover the palatal region to prevent discomfort. The thin mucosa covering the palatal torus makes it prone to get ulcerations, which could expose the palatal mucosa to pathogens. 9 The constant trauma to epithelium could potentially be the source of entry of HPV into the basal keratinocytes. Nonetheless, the histopathological diagnosis of verruca vulgaris is distinctive and enough to differentiate this lesion from other white mucosal lesions in the oral cavity such as frictional keratosis. The presence of intracellular bodies and hypergranulosis, which we see in our case report is not usually seen in frictional keratosis or traumatic keratosis according to Abidullah et al 10 and Sudhakar et al. 11 In this case, the lesion was hyperkeratotic and nonscrapable, which ruled out the presence of candida infection. To the best of this author's knowledge and based on a thorough online search of previously published articles on OVV, we are the first to document OVV on a palatal torus. This finding is however not entirely surprising because palatal tori are very easily traumatized The strain of HPV involved in the pathogenesis of OVV is usually HPV type 2 and HPV type 4. 3 These have a low potential for malignant change. 12 Nonetheless, to ascertain the specific type of HPV infection, a polymerase chain reaction assay is necessary. Genital warts or condyloma acuminatum have been shown to carry multiple strains of HPV (both low and high-risk types). 13 With the rising trend of oral sexual practice, reports of HPV infection from genital to oral regions are expected to rise accordingly. 14 Although rare, Atullah et al documented a case of OVV on the lip which transformed into oral squamous cell carcinoma in 4 years when left untreated. 15 Verruca vulgaris on extraoral regions such as the eyelid have also been reported with malignant change into a combination of squamous cell carcinoma and basal cell carcinoma. 16 The benign nature of OVV should not be taken for granted, prompt excisional biopsies are warranted to prevent any potential for malignant change. In this case, concomitant torectomy was done to reduce recurrence, this is based on the belief that trauma to the torus was how HPV inoculated the overlying palatal mucosa.

Note
There is a sign in the patient consent, but it is the patient's right cannot show or tell the patient's name.
Authors' Contributions L.K.K. and L.E.C. supported in the conceptualization of study and in writing original draft preparation of manuscript. L.K.K. developed methodology, conducted formal analysis, carried out data curation, and helped in reviewing and editing the manuscript. B.Y. dedicated to investigation and project administration. B.P.B. helped in visualization and final approval of the manuscript. B.P.B. and N.W. provided supervision and agreement to the accountable. D.R. distributed the resources and L.E.C. approved the validation.

Funding
None.