Granular Cell Ameloblastic Fibroma Research Articles

Ameloblastic fibroma and related lesions: current pathologic concept.

Ameloblastic fibroma (AF) is a true mixed tumor, in which the epithelial and the ectomesenchymal elements are neoplastic. There are two rare variants of AF; granular cell AF and peripheral AF. Ameloblastic fibrosarcoma is a rare tumor, and is regarded as the malignant counterpart of the benign AF. Recent immunohistochemical study using MIB-1 shows labelling indices in the mesenchymal component of the recurrent AF and ameloblastic fibrosarcoma are quite high, in contrast with the conventional AF. Ameloblastic fibrodentinoma is a histologic variant of AF in which dentin or dentinoid tissue has formed, but there is no eveidence that ameloblastic fibrodentinoma exhibit a different biologic behavior than ordinary AF. Ameloblastic fibro-odontoma is a lesion similar to AF, but also showing inductive changes that lead to the formation of both dentin and enamel. Some lesions diagnosed as ameloblastic fibro-odontoma are probably developing odontoma, but the others should not be considered as hamartomatous in nature, since there are rare cases of ameloblastic fibro-odontoma showing true neoplastic behavior, and since the existence of malignant variant is evident. In revised WHO's classification of odontogenic tumors, the terms "ameloblastic fibrodentinoma" and "dentinoma" are used synonymously, however, there are histologic difference between several cases reported previously as "dentinoma" and ameloblastic fibrodentinoma.

Central granular cell tumor of the jaw: An electron microscopic and immunohistochemical study

Central granular cell tumor of the jaw was formerly known as granular cell ameloblastic fibroma; recently, the term central granular cell odontogenic fibroma has been proposed. This study attempts to determine the ultrastructural features and selected immunohistochemical properties of the tumor cells. Four formalin-fixed specimens were processed for electron microscopy, and for immunohistochemical staining with antiactin, anti-glial fibrillary acidic protein, and OKT6 (CD1) with the avidin-biotin-peroxidase complex method. Tumor cells contained many primary lysosomes, autophagic vacuoles, and phagocytic vacuoles. The phagocytic vacuoles appeared to contain collagen fibrils. Tumor cells stained positive with antiactin and OKT6 (CD1), and negative with anti-glial fibrillary acidic protein. The results indicate that tumor cells are actively phagocytic and suggest that tumor cells might arise from Langerhans' cells.

Immunoreactivity of granular cell lesions of skin, mucosa, and jaw.

Granular cell lesions from many different sites share similar light and electron microscopic features. Immunologically, however, these lesions do not appear to be a homogenous group. This study determines the extent of immunologic heterogeneity of granular cell lesions from a wide variety of sites in skin, mucosa, and jaw. Thirty-one granular cell lesions (26 granular cell tumors [GCT] and five other granular cell lesions) from 18 different sites were evaluated immunohistochemically for keratins, vimentin, desmin, muscle actin, ACT, HLA-DR, and S-100 protein. Paraffin-embedded sections were utilized with an avidin-biotin complex immunoperoxidase technique. Except for ameloblastomas, all lesions were negative for keratin and positive for vimentin. All lesions were negative for desmin and actin. Positive ACT reactivity was found in one of seven GCT of tongue, a colonic lesion, a nose lesion, and a granular cell ameloblastic fibroma. All lesions were positive for HLA-DR except a few in which fixation appeared inadequate. S-100 immunoreactivity was found in all lesions except the congenital epulis, a GCT of the skin of the nose, a colonic lesion, and the odontogenic tumors. The antigenic profile of GCT of skin and mucosa is consistent with Schwann cell origin. However, some GCT and other granular cell lesions appear to be derived from macrophages, epithelial cells, or other cells. The expression of HLA-DR by granular cells is believed to be unrelated to cellular origin but rather to some common immunologic function.

Central odontogenic fibroma, granular cell variant A case report with S-100 immunohistochemistry and a review of the literature

We have identified 14 cases that over the last 40 years have been reported under a series of names, most commonly granular cell ameloblastic fibroma. An additional case in the mandibular premolar region of a 45-year-old woman is described. The tumor was conservatively removed and 4 years later shows no evidence of recurrence. On the basis of our examination of the clinical and histologic features of this lesion and a comparison with the previous cases, we agree with the recent suggestion that the tumor should be designated as a central odontogenic fibroma, granular cell variant. By means of S-100 protein immunostaining techniques, the granular cells in this lesion were compared with the granular cell population in a granular cell tumor (myoblastoma) and the mesenchymal component of an ameloblastic fibroma. The results reveal a lack of S-100 protein reactivity in the granular cells of the central odontogenic fibroma and suggest an origin of those cells different from the origin of cells in a granular cell tumor.

Granular cells in odontogenic and non-odontogenic tumours

Granular cells can occur in various odontogenic and non-odontogenic tumours. 5 granular cell lesions, one granular cell ameloblastoma, one so-called granular cell ameloblastic fibroma and three granular cell tumours were examined immunohistochemically for the intermediate filaments cytokeratin, vimentin, desmin, neurofilaments and the neural markers NSE and S-100 protein. The granular cell tumors (granular cell myoblastoma) showed positive staining for vimentin and S-100 protein. Only vimentin could be demonstrated in the granular cells of the so-called granular cell ameloblastic fibroma, whereas the granular cell ameloblastoma showed positive staining only for cytokeratin. A positive reaction with S-100 protein was not found in any of the odontogenic tumours. In our opinion the mesenchymal odontogenic granular cell is a fibroblast, whereas the epithelial granular cell is derived from enamel epithelium. The term "granular cell ameloblastic fibroma" is a misnomer, as a number of these tumours are probably central odontogenic fibromas exhibiting granular cell transformation.

Central granular cell odontogenic fibroma

First described in 1962, the so-called granular cell ameloblastic fibroma has been a rarely reported benign odontogenic tumor. On reviewing the literature, we have identified eight previously reported cases. All cases involved well-circumscribed radiolucencies in women who ranged in age from 53 to 65 years. Seven lesions occurred in the posterior body of the mandible, and one occurred in the premolar region of the maxilla. All lesions were treated with surgical excision, and no recurrences were identified during follow-up periods of 6 to 144 months. Two additional cases also appear to represent instances of this neoplasm, which bring the total number identified to ten. We describe the clinical, radiographic, and histopathologic features of two additional cases and suggest reasons the tumor should be referred to as central odontogenic fibroma, granular cell variant.

Granular cell ameloblastic fibroma, ultrastructure and histogenesis

A case of peripheral granular cell ameloblastic fibroma arising in the right upper premolar gingiva in a 34-year-old Japanese woman is reported. Ultrastructural examination revealed a clear separation of granular cells and epithelial component, and indicated granular cells were derived from mesenchymal cells, probably fibroblasts. Direct communication between the overlying gingival epithelium and the epithelial component of the tumor was found. It is postulated that residual ectomesenchymal influence may be responsible for proliferation of both epithelial and mesenchymal components which subsequently are transformed into granular cells.

Central granular-cell tumor of the jaws (the so-called granular-cell ameloblastic fibroma)

Central granular-cell tumor of the jaws (the so-called granular-cell ameloblastic fibroma)

Ultrastructure of granular cell ameloblastoma.

To our knowledge, this is the first description of the ultrastructure of the granular cell ameloblastoma, an odontogenic tumor. The granular cells of this tumor are shown to be epithelial in origin. The organelles resulting in their cytoplasmic eosinophilia, as seen in the light microscope, are mainly pleomorphic, osmiophilic lysosome-like granules. A comparison with granular cell myoblastoma shows a striking morphological similarity between the cytoplasmic granules of these two lesions. We conclude that the granular cell ameloblastoma and the granular cell myoblastoma, probably along with the granular cell ameloblastic fibroma and the congenital epulis, constitute a group of lesions in which the lysosomes are the common denominator as the expression of their cytoplasmic eosinophilia.

Granular-cell ameloblastic fibroma: Report of two cases

Two cases of an unusual odontogenic tumor have been presented. Both lesions were considered to be ameloblastic fibromas with extensive granular-cell change in the mesodermal component. The patients were considerably older than the typical patient with ameloblastic fibroma. We suggest that the granular-cell alteration in the mesodermal component represents an aging or degenerative response in the lesion. These lesions possibly are related to the granular-cell congenital epulis. The granular-cell ameloblastic fibroma appears to be a quite benign lesion, and curettage is probably sufficient for cure.

Granular cell ameloblastic fibroma. Report of 2 cases in adults, with observations of its similarity to congenital epulis.

Granular Cell Ameloblastic Fibroma: Report of 2 Cases in Adults, with Observations on its Similarity to Congenital Epulis Get access Rex D. Couch, M.D., Rex D. Couch, M.D. Indiana University School of Medicine, and Indiana University School of Dentistry, Indianapolis, Indiana Search for other works by this author on: Oxford Academic Google Scholar Estell E. Morris, D.D.S., Estell E. Morris, D.D.S. Indiana University School of Medicine, and Indiana University School of Dentistry, Indianapolis, Indiana Search for other works by this author on: Oxford Academic Google Scholar Frank Vellios, M.D. Frank Vellios, M.D. Indiana University School of Medicine, and Indiana University School of Dentistry, Indianapolis, Indiana Search for other works by this author on: Oxford Academic Google Scholar American Journal of Clinical Pathology, Volume 37, Issue 4, 1 April 1962, Pages 398–404, https://doi.org/10.1093/ajcp/37.4.398 Published: 01 April 1962 Article history Received: 25 September 1961 Accepted: 10 January 1962 Published: 01 April 1962