True Fibroma of Alveolar Mucosa

Benign fibrous overgrowths are often found in the oral cavity, almost always being reactive/irritational in nature. However, benign mesenchymal neoplasms of the fibroblasts are extremely uncommon. Here we report a case of “True Fibroma of Alveolar Mucosa” for its rarity. 1. Introduction Fibroma is a benign neoplasm of fibroblastic origin, rare in the oral cavity [1]. It is said that the majority of the fibromas occurring in the oral cavity are reactive in nature and represent a reactive hyperplasia of fibrous connective tissue in response to local irritation or trauma rather than being a true neoplasm [2]. The occurrence of irritation fibromas among the South Indian population was found to be 39.1% [3]. Stout said that “it is exceedingly difficult to decide whether or not there is true benign neoplasm composed of fibroblasts” [2]. Since true fibromas of oral and maxillofacial areas are infrequent [4], the case below is one of a kind. The histologic criteria of a true fibroma were first described by Barker and Lucas. Three more cases of true gingival fibroma have been reported in literature since then [5]. We describe a similar case of a true fibroma in the maxillary alveolar mucosa. 2. Case Report A 60-year-old male was examined for a two-month-old solitary swelling measuring approximately 2.5 × 2.5？cm in the right middle third of the face. Intraorally, on palpation it was ovoid and firm in consistency with respect to 16 and 17 region (Figure 1(a)). Radiographic examination revealed no calcifications. Irritation fibroma, neurofibroma, peripheral ossifying fibroma, and benign tumors of nerve and muscle origin were provisionally diagnosed. The encapsulated lesion, noted to be located between periosteum and alveolar mucosa, was excised under local anaesthesia and sent for histopathological evaluation (Figure 1(b)). Figure 1: (a) Well circumscribed lesion in the alveolar mucosa. (b) Encapsulated tumour on surgical exploration. A soft tissue specimen, pinkish white in colour, irregular in shape, and firm in consistency, that measured approximately 3.5 × 3 × 3？cm was received (Figure 2(a)). The cut surface of the gross specimen was whitish in colour (Figure 2(b)). Difficulty in sectioning the specimen prompted that the tumour was fibrous in nature. Figure 2: (a) Gross specimen of the excised tumour. (b) Cut surface of the excised tumour. Histopathology revealed a flattened hyperparakeratotic stratified squamous epithelium overlying a well circumscribed encapsulated mass of dense collagenous stroma. The stroma was composed of numerous spindle shaped plump