Oral Focal Mucinosis, an uncommon entity: Report of three cases

Abstract

<h3>Introduction</h3> Oral focal mucinosis (OFM) is a rare soft tissue lesion of unknown etiology and it is considered the oral counterpart of cutaneous focal mucinosis or cutaneous myxoid cyst. The pathogenesis of OFM may be explained by fibroblast overproduction of hyaluronic acid. Clinically, it appears as painless swelling of the same color as the surrounding mucosa. The gingiva is the most common site and the diagnosis is established only by histopathological and immunohistological examination. <h3>Materials and Methods</h3> We present three cases of gingival oral focal mucinosis. Case 1: 40 year-old womatn with painless and slow-growing swelling of two years of evolution at buccal mandibular gingiva, between lateral incisor and canine. The lesion measured 2 cm. and exhibited the same color as the overlying mucosa; there was not radiographic involvement. Case 2: 48 year-old female with a hard palatal swelling. The lesion was sessile, firm, and not color change Case 3: 36 year-old male with a painless and same color as the normal mucosa gingival swelling. The lesion was between central and lateral right incisors, it was sessil and measured 1.5 cm Results In the three cases excisional biopsy was performed and histopathologically they shown the proliferation of elongated and mucinous material in a myxoid matrix. This myxoid stroma was surrounded by collagenous fibrous connective tissue and covered with squamous epithelium. Histochemical staining with Alcian blue was positive in the mucinous areas Conclusions These three cases are significant clinically as well as histopathologically. The lesions clinically mimic an ossifying peripheral fibroma or a fibroma. Thus, the histopathological and histochemical findings with special stains, such as Alcian blue, are determinant to establish the diagnosis of these conditions. Treatment is the complete surgical excision and its recurrence is not reported.