Solitary fibrous tumour of the oral cavity: clinicopathological and immunohistochemical characterization of three cases

Abstract

Solitary fibrous tumour (SFT) is an uncommon mesenchymal neoplasm rarely located in the oral cavity. To characterize further oral SFT, we describe three new cases. Each tumour originated in the buccal mucosa of a middle-aged/elderly patient. Histological examination showed well-circumscribed tumours with densely cellular areas alternating with hypocellular areas in a variedly collagenous, vascular stroma. Mast cells were abundant. The spindle-shaped, neoplastic cells immunostained strongly for CD34 antigen and vimentin and weakly for bcl-2, but not for epithelial cell markers, alpha-smooth muscle actin, or neurofilament or S-100 proteins. Compatible with the virtual absence of mitoses and of marked nuclear atypia, the overall frequency of proliferating cells expressing Ki-67 was low. The expression of CD34 was useful in the differential diagnosis. The consistent location in the cheek and expansion of one tumour after local trauma does not preclude a traumatic element in the development of oral SFT.

An Aggressive Solitary Fibrous Tumor with Evidence of Malignancy: A Rare Case Report

“…Recently, the ubiquitous nature of this tumor has been recognized with reports of SFT arising in various extrapleural sites like respiratory tract, lung, breast, somatic tissue, mediastinum, head, and neck, etc. However, involvement of oral cavity is a rarity [3] with buccal mucosa being the common site of occurrence [4].…”

Tumor fibroso solitario de la cavidad oral : Reporte de dos casos.

“…Aunque las células están distribuidas al azar, ellas pueden mostrar un padrón estoriforme (2,11,17). El tumor usualmente exhibe inmunoreactividad para vimentina, CD34, bcl-2, CD99 y factor XIIIa, pero es negativo para actina músculo específico, actina músculo liso, S100 y citoqueratinas (2,8,12,15,(17)(18)(19). Similar a CD34, CD99 es un marcador consistente-mente encontrado en el TFS, en cuanto EMA (antígeno epitelial de membrana) y desmina pueden ser positivos en casos esporádicos (13).…”

“…Similar a CD34, CD99 es un marcador consistente-mente encontrado en el TFS, en cuanto EMA (antígeno epitelial de membrana) y desmina pueden ser positivos en casos esporádicos (13). La molécula CD34 es una glicoproteína transmembrana de cadena única relacionada a subgrupos de células progenitoras hematopoyéticas mieloides (8,20). Según Regezi et al (1992) (16), los dendrocitos submucosos orales exhiben positividad para CD34 y el factor XIIIa.…”

“…Afterwards it was described in many extrapleural sites such as the lungs, mediastinum, peritoneum, spinal cord, soft tissues, sinonasal tract, nasopharynx, thyroid, orbit, periosteum, liver, renal capsule, skin, oral cavity and salivary glands (2-8). We found only 36 benign oral SFT reported in the English literature (4,(8)(9)(10)(11)(12). Clinically, it presents as a movable, asymptomatic, well-circumscribed submucous nodule of variable size, covered by normal mucosa (9).…”

“…Posteriormente fue descrito en varios sitios extrapleurales como los pulmones, mediastino, peritoneo, médula espinal, tejidos blandos, tracto sinonasal, nasofaringe, tiroides, cavidad orbitaria, periostio, hígado, cápsula renal, piel, cavidad oral y glándulas salivales (2)(3)(4)(5)(6)(7)(8). En la literatura inglesa, encontramos relatados solamente 36 casos de TFS oral benigno (4,(8)(9)(10)(11)(12). Clíni-camente se presenta como un nódulo submucoso de variable tamaño, móvil, asintomático, bien circunscrito y cubierto por mucosa normal (9).…”