Solitary fibrous tumours of the lower gingiva: a case report

Slow-Growing Large Irritation Fibroma of the Anterior Hard Palate: A Case Report Using Immunohistochemical Analysis

Irritation fibromas are recognized as fibrous lesions, usually reactive hyperplasias; however, the mechanism of enlargement is unclear. This paper reports on an abnormally large irritation fibroma of extremely gradual growth. The immunohistochemical features (CD34, α-SMA, vimentin, Ki-67, and TGF-α) of this irritation fibroma are presented to distinguish reactive hyperplasia from other true fibrous neoplasm diseases. In the only previous study, it was reported that the expression of TGF-α might be associated with the development of oral fibromas. Therefore, we investigated the relationship between this exceptionally-large fibrous lesion of extremely slow growth and the immunohistochemical reactivity of TGF-α, finding that, in contrast to the previous study, TGF-α was not expressed. This is the first study to evaluate the enlargement mechanism of such a large irritation fibroma using the approach of immunohistochemical analysis, and it indicates that such analysis can help elucidate the diverse causes and enlargement mechanisms of irritation fibromas.

Solitary fibrous tumor of the buccal vestibule: report of two cases

Solitary fibrous tumor (SFT) is a rare benign tumor that occurs most frequently in the pleura. It is considered rare in the maxillofacial area. Two new cases of SFT of the buccal vestibule are reported. The previously reported cases of oral SFT are reviewed. The tumors were composed of spindle-shaped cells that were arranged haphazardly and were positive for CD-34, BCL-2, CD-99 and vimentin. Although rare, SFT should be included in the differential diagnosis of oral soft tissue tumors. The clinical presentation and imaging can provide the clinician a better tool for preoperative diagnosis.

Solitary fibrous tumor of the oral cavity: clinicopathologic and immunohistochemical study of 21 cases

We describe clinical, morphologic, and immunohistochemical features of 21 cases of solitary fibrous tumor presenting in the oral cavity. There were 9 male and 12 female patients with a median age of 51 years (range 37-83). The most common locations included the buccal mucosa (the most common site), lip, maxillary or mandibular vestibule and tongue. Histopathologic examination showed well-circumscribed tumors with two well-defined patterns: the classic pattern with densely cellular areas alternating with hypocellular areas in a variably collagenous, vascular stroma and a more uniformly sclerotic pattern with only subtle classic areas. The spindle-shaped neoplastic cells consistently showed immunoreactivity for antibodies directed against CD34. Five of nineteen cases (26%) were reactive for CD99 and 19 of 19 for Bcl-2. Follow-up information was available in 17 cases and averaged 54 months, with no evidence of recurrence or metastasis in any of these patients. Awareness that solitary fibrous tumor may present in the oral cavity is important so that confusion with other spindle cell neoplasms can be avoided. We also briefly describe the differential diagnosis and compare this series, the largest single series of intraoral SFT, to cases previously reported in the literature.

Solitary fibrous tumor of the oral cavity: the need for an extensive sampling for a correct diagnosis

BACKGROUND

Solitary fibrous tumor (SFT) is an uncommon but well-characterized soft tissue tumor that was first described as a pleural lesion and now is considered ubiquitous, having been detected at many extra-pleural sites (abdominal cavity, orbit, upper respiratory tract, and oral cavity). Histologically, SFT may show wide morphological variability of both its cellular and stromal components, which may lead to incorrect diagnosis especially when dealing with small incisional biopsies.

MATERIALS

We report on the clinical, morphological and immunohistochemical features of eight SFT occurring in the oral cavity.

RESULTS

Microscopically all eight tumors showed widely variable morphological features in terms of cellular density and stromal architecture, thus simulating benign fibrous histiocytoma, schwannoma, hemangiopericytoma or low-grade sarcoma in distinct areas of the same lesion. Among these eight cases, five had been diagnosed as SFT, two as benign fibrous histiocytoma and one as low-grade sarcoma.

CONCLUSIONS

In consideration of the heterogeneous morphological appearance of SFT, inaccurate sampling of the mass may lead to misdiagnosis and inappropriate treatment. Therefore, an accurate histological examination of multiple tissue sections is advised, along with the use of appropriate immunostains.

Comparison of sporadic sclerotic fibroma and solitary fibrous tumor in the oral cavity

Sporadic sclerotic fibroma (SF) and solitary fibrous tumor (SFT) arising in the oral cavity are very rare. In this report, we describe two cases of oral pathology, one involving SF and the other involving SFT. Both cases presented with well- circumscribed, firm nodules with similar gross findings. However, the histologic findings of the SF and SFT showed rather distinct features. The SF was composed of hyalinized sclerotic collagen bundles arranged in a whorled pattern, whereas the SFT was formed by spindles cells arranged in hypo- and hypercellular areas. The immunohistochemical findings were similar in both cases; there was positivity for vimentin, CD34, and CD99, but bcl-2 positivity was only seen in the SFT. Although their histopathologies are similar, SF and SFT should be considered in the differential diagnosis of soft tissue tumors in the oral cavity.

Solitary Fibrous Tumor of the Floor of the Mouth: Case Report and Review of the Literature

Solitary fibrous tumor is an uncommon spindle cell neoplasm that is believed to be of mesenchymal origin. Rarely does it originate in the oral cavity, and only 1 case of this lesion in the floor of the mouth has been previously reported. We describe a new case of solitary fibrous tumor arising from the soft tissues of the floor of the mouth.

Endonasal endoscopic resection of an ethmoidal solitary fibrous tumor

Solitary fibrous tumor (SFT) is an uncommon spindle cell tumor that typically arises at the level of the pleura in adults. However, SFT has also been reported in various extrapleural sites including orbit, meninges, liver, lung, salivary glands, retroperitoneum, mediastinum. In the head and neck region, SFT has been documented in the external auditory canal, larynx, thyroid, sublingual gland, tongue, parapharyngeal space and the infratemporal fossa. The nose and the paranasal sinuses are a rare site for SFT with only 14 publications in the world literature. We present an additional case of a SFT arising at the level of the right ethmoid sinus successfully removed in one piece endoscopically and review the corresponding literature.

Solitary fibrous tumour of the oral cavity with histological features of aggressiveness

We operated on a 65-year-old woman and removed a solitary fibrous tumour from her oral mucosa. Microscopically we found marked atypia, abundant necrosis, increased number of mitotic figures (>4 in 10 high-power fields) and hypercellularity. The tumour cells were strongly stained for CD34. There has been no recurrence after 18 months.

Solitary fibrous tumor arising in the sphenoethmoidal recess: a case report and review of the literature

Recently, solitary fibrous tumors (SFTs) have been reported in the head and neck area, such as the nasal cavity, thyroid, salivary gland, etc. We present a rare case of SFT which arose from the sphenoethmoidal recess of the nasal cavity, penetrating into the sphenoid sinus, and which showed different intensities on magnetic resonance imaging (MRI) according to the occupied locations. T2 weighted magnetic resonance (MR) images showed low intensity in the nasal cavity, and iso-intensity in the sphenoid sinus. Enhancement with gadolinium contrast on T1-weighted images was more remarkable in the sphenoid sinus than in the nasal cavity. While the tumor in the nasal cavity showed abundant collagen and high cellularity in microscopic examination, numerous small vessels and dilated vascular spaces were remarkable in the tumor of the sphenoid sinus. MRI findings corresponded to pathological findings. We review SFTs in the head and neck area in the English literature.