You are in: eMedicine Specialties > Dermatology > DISEASES OF THE ORAL MUCOSA Oral Fibromas and FibromatosesArticle Last Updated: Feb 7, 2007AUTHOR AND EDITOR INFORMATIONAuthor: David A Lederman, DMD, Chief, Oral Pathology Section, Department of Dentistry, Newark Beth Israel Medical Center; Director, Lakewood Pathology Associates David A Lederman is a member of the following medical societies: American Academy of Oral and Maxillofacial Pathology, American Academy of Oral Medicine, and American Dental Association Coauthor(s): Maria L Fornatora, DMD, Associate Professor, Departments of Oral and Maxillofacial Pathology, Medicine, and Surgery, Temple University School of Dentistry; Consulting Staff, Department of Oral and Maxillofacial Surgery, Temple University Hospital Editors: Mark G Lebwohl, MD, Chairman, Department of Dermatology, Mount Sinai School of Medicine; Richard P Vinson, MD, Assistant Clinical Professor, Department of Dermatology, Texas Tech University School of Medicine; Consulting Staff, Mountain View Dermatology, PA; Drore Eisen, MD, DDS, Consulting Staff, Department of Dermatology, Dermatology Research Associates of Cincinnati; Catherine Quirk, MD, Clinical Assistant Professor, Department of Dermatology, Brown University; Dirk M Elston, MD, Director, Department of Dermatology, Geisinger Medical Center Author and Editor Disclosure Synonyms and related keywords: irritation fibroma, focal fibrous hyperplasia, giant cell fibroma, peripheral cemento-ossifying fibroma, peripheral ossifying fibroma, calcifying fibrous epulis, peripheral fibroma with calcification, peripheral odontogenic fibroma, fibromatosis, aggressive juvenile fibromatoses, myofibroma, myofibromatosis BACKGROUNDFibrous growths of the oral soft tissues are fairly common and include a diverse group of reactive and neoplastic conditions. Some of these conditions are discussed elsewhere in this eMedicine journal. For example, the term epulis fissuratum refers to epithelial and fibrous hyperplasia specifically related to, and the result of, trauma from the border of a removable denture. It may be viewed as the mucosal counterpart of acanthoma fissuratum. FIBROMAThe fibroma, also referred to as irritation fibroma, is by far the most common of the oral fibrous tumorlike growths. While the terminology implies a benign neoplasm, most if not all fibromas represent reactive focal fibrous hyperplasia due to trauma or local irritation. Although the term focal fibrous hyperplasia more accurately describes the clinical appearance and pathogenesis of this entity, it is not commonly used. A fibroma may occur at any oral site, but it is seen most often on the buccal mucosa along the plane of occlusion of the maxillary and mandibular teeth. It is a round-to-ovoid, asymptomatic, smooth-surfaced, and firm sessile or pedunculated mass. The diameter may vary from 1 mm to 2 cm. The surface may be hyperkeratotic or ulcerated due to repeated trauma. Fibromas are most often observed in adults, but they may occur in individuals of any age and either sex. The clinical differential diagnosis of a fibroma includes giant cell fibroma, neurofibroma, peripheral giant cell granuloma, mucocele, and benign and malignant salivary gland tumors. Histologically, a fibroma is an unencapsulated, solid, nodular mass of dense and sometimes hyalinized fibrous connective tissue that is often arranged in haphazard fascicles. A mild chronic inflammatory infiltrate may be present. The surface epithelium may be hyperkeratotic, either hyperplastic or atrophic, and it may be ulcerated. Conservative excisional biopsy is curative, and its findings are diagnostic. Recurrence is possible however, if the offending irritant persists (Barker, 1967; Esleili, 2005). Unusual subtypes
GIANT CELL FIBROMAA giant cell fibroma has a distinctive histologic appearance that sets it apart from a conventional fibroma. It appears as an asymptomatic sessile or pedunculated nodule that is smaller than 1 cm in diameter. Often, it has a bosselated or somewhat papillary surface. Most cases are diagnosed in persons aged 10-30 years. No sex predilection has been reported. The most common sites are the mandibular gingiva, followed by the maxillary gingiva, the tongue, and the palate. The clinical differential diagnosis includes squamous papilloma, irritation fibroma, pyogenic granuloma, and peripheral giant cell granuloma. Microscopically, a giant cell fibroma is an unencapsulated mass of fibrous connective tissue that contains numerous characteristic large, plump, spindle-shaped and stellate fibroblasts, some of which are multinucleated. These cells are easily observed in the peripheral areas of the lesion, while the more central areas contain typical fusiform fibroblasts. The surface epithelium is often corrugated and atrophic. In contrast to an irritation fibroma, a giant cell fibroma has thin, elongated rete ridges. Because of its histologic similarity, some consider this to be the oral equivalent of fibrous papule of the face. Conservative excisional biopsy is curative, and its findings are diagnostic. Recurrence is rare (Houston, 1982; Esmeili, 2005). PERIPHERAL CEMENTO-OSSIFYING FIBROMAA peripheral cemento-ossifying fibroma is also known as a peripheral ossifying fibroma, a calcifying fibrous epulis, or a peripheral fibroma with calcification. It is a reactive gingival lesion that is believed to arise from cells of the periodontal ligament or periosteum. Most often, it is located in the gingival papilla between adjacent teeth. A peripheral cemento-ossifying fibroma manifests as a sessile or pedunculated mass, which is often ulcerated and generally has a diameter of less than 2 cm. Peripheral cemento-ossifying fibromas may occur in persons of any age but are most often seen in persons aged 10-20 years. Females are affected more often than males by a ratio of approximately 3:2. The maxillary gingiva is involved more often than the mandibular gingiva; usually, the anterior region is affected. Mobility and/or migration of adjacent teeth is occasionally observed. Microscopically, fibrous proliferation is accompanied by increased cellularity with plump, immature fibroblasts and variable amounts of calcified material. This material may be osteoid, cementoid, or dystrophic. In some cases, this characteristic pattern is only part of the pattern of a larger lesion that may resemble an irritation fibroma or pyogenic granuloma. Surface ulceration is common. The clinical differential diagnosis of a peripheral cemento-ossifying fibroma includes inflammatory gingival hyperplasia, peripheral giant cell granuloma, pyogenic granuloma, fibroma, and peripheral odontogenic fibroma. Treatment consists of excision down to the periosteum and the elimination of any local irritants. Care must be taken to maintain or reestablish acceptable gingival architecture and periodontal integrity. A recurrence rate of 16% is reported. Even in cases complicated by recurrence, reexcision is generally successful, with the retention of the associated teeth (Buchner, 1987; Gardner, 1982; Esleili, 2005). PERIPHERAL ODONTOGENIC FIBROMAA peripheral odontogenic fibroma is a rather uncommon neoplasm that is believed to arise from odontogenic epithelial rests in the periodontal ligament or the attached gingiva itself. The entity, formerly confused with peripheral cemento-ossifying fibroma, is considered to be the extraosseous counterpart of the central odontogenic fibroma of the World Health Organization type. A peripheral odontogenic fibroma manifests as a firm, slowly growing, sessile, and nodular growth of the gingiva, most often on the mandibular buccal or labial aspect. It occurs in persons of a wide age range and affects both sexes equally. The clinical differential diagnosis of a peripheral odontogenic fibroma includes inflammatory gingival hyperplasia, peripheral cemento-ossifying fibroma, and peripheral giant cell granuloma. Microscopically, the tumor consists of an unencapsulated mass of interwoven cellular fibrous connective tissue that contains scattered nests or strands of odontogenic epithelium. Myxoid foci, osteoid, cementoid, or dystrophic calcifications are sometimes seen. The surface generally is not ulcerated. Treatment consists of conservative excision performed with care to maintain or reestablish the gingival architecture and periodontal integrity. Recurrence is rare (Gardner, 1982). FIBROMATOSISThe fibromatoses represent a group of infiltrating fibrous proliferations with a biologic behavior and microscopic appearance intermediate between those of benign fibrous lesions and fibrosarcomas. In the head and neck region, they are sometimes referred to as juvenile or aggressive juvenile fibromatoses. Patients of any age may be affected, but three quarters of all cases are diagnosed when the patient is younger than 10 years. No significant sex predilection is apparent. The most frequent site of occurrence is the soft tissues adjacent to the mandible. Intraoral presentations are rare, but they most often involve the tongue or buccal mucosa. Lesions appear as firm, painless, poorly demarcated masses with a variable growth rate. They are locally aggressive and often cause resorption of the underlying bone when present. A desmoplastic fibroma occurring within the medullary cavity of bone is considered to be the intraosseous counterpart of the soft tissue fibromatosis. The differential diagnosis of a soft tissue fibromatosis is myofibroma and rhabdomyosarcoma. Microscopically, fibromatosis is characterized by a poorly delineated, infiltrating cellular proliferation of mature spindle cells arranged in streaming and interlacing fascicles. Collagen production is usually prominent. Infiltration of the adjacent structures is common at the periphery, but cellular atypia is not present. Treatment consists of wide excision. The reported recurrence rate of 24% for oral fibromatosis is considerably lower than the 50-70% rate reported for fibromatoses of the entire head and neck region (Casavecchia, 2004; Coletta, 2006; Fowler, 1994; Neville, 2002; Seper, 2005; Valy, 1990; Watzinger, 2005). Gingival fibromatosis deserves separate consideration. It may be hereditary, idiopathic, or drug induced. The hereditary and idiopathic forms manifest as isolated or diffuse firm, noninflammatory enlargements of the keratinized gingiva. Although the process is typically nonpainful, the enlarged gingiva may eventually cover large portions of the clinical crowns of teeth and erode the underlying bone. Recurrence is common following surgical excision. The hereditary form may also manifest as a component of a larger complex syndrome (eg, gingival fibromatosis with hypertrichosis syndrome, Zimmermann-Laband syndrome, Cross syndrome). Both the idiopathic and hereditary forms are rare, limited to the gingiva, and most often affect children. Drug-induced gingival overgrowth has been associated with systemic use of phenytoin, cyclosporin, and calcium channel blockers (Dongari-Bagtzolou, 2004; Lederman, 1995). MYOFIBROMA AND MYOFIBROMATOSISMyofibroblasts are spindle-shaped cells with features of both fibroblasts and smooth muscle cells. Myofibroblasts have been identified in lesions other than myofibromas, but when they are the predominant cell type in a tumor, the terms myofibroma (if solitary) or myofibromatosis (if multicentric) are applied. The tumors are benign, and, although myofibromatosis is similar to fibromatosis in many ways, its behavior tends to be less aggressive. Tumors of myofibroblasts may occur in either sex and in patients of all ages, with a mean patient age of 26.6 years. Solitary myofibromas have a head and neck predilection, with the mandible being the most common site of occurrence. The most common oral soft tissue sites are the tongue, lips, and buccal mucosa. Tumors also have been described in the dermis, soft tissues, viscera, and bone. Intraosseous jaw lesions most often manifest as well-defined unilocular or multilocular radiolucencies. Oral soft tissue lesions typically manifest as firm, slow growing, submucosal nodules or exophytic masses with a diameter of 0.3-5 cm. Although patients are frequently asymptomatic, the lesions may be tender or even painful. The clinical differential diagnosis for oral myofibroma includes irritation fibroma, fibromatosis, peripheral giant cell fibroma, neurofibroma, leiomyoma, and benign and malignant neoplasms of the minor salivary glands. Treatment for oral myofibromas is conservative excision. The recurrence rate is low, and spontaneous regression has been reported (Corson, 2002; Foss, 2000; Jones, 1994; Lingen, 1995; Neville, 2002; de Souza, 1999; Scheper, 2005; Weiss, 2001). MULTIMEDIA
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Oral Fibromas and Fibromatoses excerpt Article Last Updated: Feb 7, 2007 | ||||||||||||||||||||||||||||||||||||||||