CLINICOPATHOLOGIC REVIEW:
Papillary Lesions of the Oral Cavity blunted than those of the SP. The projections are surfaced by acanthotic stratified squamous epithelium with limited keratin formation, consistent with the pink coloration of these lesions. 2 Keratin-filled crypts are commonly seen between the projections. Dysplasia should not be seen. CA found in proximity to minor salivary glands must be distinguished from ductal papilloma. 7 Koilocytes are less prominent in oral lesions, when compared to genital lesions, and are less prominent than those seen in SP or VV. 2 Treatment generally consists of conservative surgical excision. CA should be removed because of the risk of spread to surrounding tissues or to other individuals. Laser and cryotherapy can be used, but a concern is the creation of a potentially infectious plume of viral particles that expose the surgical team to airborne HPV. 2 Topical agents such as imiquimod, sinecatechins, and podopyllotoxin are used on genital lesions, but are not routinely utilized to treat oral lesions. A small percentage of CA may be infected with high risk HPV types 16 or 18, which are associated with an increased potential for malignant transformation.
CA is usually larger than the lesion presented in our case. It was thus considered lower on our differential diagnosis. Additionally, the lesion was solitary, whereas CA shows a tendency to occur in clusters. Finally, SP are more common intraorally than CA. But given the clinical similarities and the patient’ s social history suggesting the possibility of high risk behavior, CA should be considered in the differential.
D. Verruciform xanthoma( VX). VX is a rare, benign lesion consisting of hyperplastic epithelium and a characteristic defining feature of a subepithelial accumulation of lipid-laden histiocytes. It is estimated to occur in less than 1 percent of the population. 9 No definitive confirmation of a viral role is currently known in the development of this lesion. The etiology of VX is currently unknown, but is thought to be due to an immune response to localized trauma or damage to the epithelium, owing to the presence of the foamy macrophages. 10 It is also thought that VX tend to appear in association with, or adjacent to, disturbed epithelium, or in association with conditions such as lupus erythematosus, lichen planus, epithelial dysplasia, squamous cell carcinoma, pemphigus, and graft-versus-host disease. Although it has been theorized that VX may indicate hyperlipidemia, no link to systemic conditions or hyperlipemia has been confirmed. 10
Clinically, VX presents as a soft, asymptomatic, sessile, white, yellow, pink, gray, or red slightly elevated mass with a roughened, pebbly, or papillary surface. It can also present as a nodule with a raised, flat surface and no papillary projections or as a verrucous appearing lesion. 9 Occasionally, it may mimic the appearance of squamous cell carcinoma, so if the lesion is clinically suspicious for malignancy, a biopsy is recommended. VX is more common in middle aged to older adults. It is more frequently seen in Caucasians, and shows a slight male predilection. 9 The most common areas of presentation are the gingiva and the alveolar mucosa, which account for about one half of all of the cases. 2 However, they can present on any oral mucosal surfaces. Histologically, the lesion presents with a papillary, parakeratinized, acanthotic surface epithelium. The keratin layer is thickened and looks pink or orange in color on an H & E stained slide. 2 The clefts between the papillary projections are usually filled with discohesive parakeratin“ flames.” A distinguishing feature consists of collections of foamy macrophages, called xanthoma cells, in the connective tissue papillae. Varying numbers of chronic inflammatory cells may be present within the connective tissue. Neutrophils may also be noted in the epithelium. Treatment of VX involves conservative surgical excision. Recurrence after removal is rare. No malignant transformation has been reported, although there have been cases of VX developing adjacent to carcinoma in situ or squamous cell carcinoma. Given the clinical appearance of the lesion presented here, which can be similar to SP, VX should be considered in the diagnosis. However, the location and exophytic nature of the lesion, the absence of nearby disturbed epithelium, as well as the rarity of VX compared to SP places this lesion lower on the list of differential diagnosis.
E. Sialadenoma papilliferum( SAP). SAP is a rare, benign salivary tumor with a papillary clinical appearance that usually involves minor salivary glands. The palate is the most common site of occurrence, but SAP can develop anywhere in the oral cavity where minor salivary glands are found. A few cases have been reported in the major salivary glands, especially the parotid.
NOV / DEC 2016 | PENNSYLVANIA DENTAL JOURNAL 39