Solitary Fibrous Tumor of the Thyroid Gland

Abstract

Solitary fibrous tumor is a soft tissue neoplasm initially described in the pleura but subsequently reported in a wide variety of locations. The clinical behavior is usually benign, but the existence of aggressive cases has been documented both in the pleura and in extrapleural sites. In this report clinical and pathologic features of seven solitary fibrous tumors of the thyroid gland are presented. Patients' ages ranged from 43 to 64 years (mean 52 years), and tumor sizes varied from 2 to 6 cm. Grossly, the tumors were white-tan and well circumscribed. Microscopically, there was a variegated, wavy, storiform, hemangiopericytic or desmoid-like arrangement of spindle cells. Trapped thyroid follicles within the tumor and peripheral jagged tumor infiltration among follicles were common. There was immunohistochemical reactivity for CD34, CD99, and bcl-2, and ultrastructural analysis of one tumor was consistent with a fibroblastic lineage. The differential diagnosis included other benign and malignant mesenchymal tumors of the thyroid, spindle cell follicular adenoma, Riedel's thyroiditis, the spindle cell, and paucicellular variants of anaplastic carcinoma, papillary thyroid carcinoma with exuberant nodular fasciitis-like stroma, and the spindle epithelial tumor with thymus-like differentiation. The cumulative data of 13 cases (comprised of the seven present cases and the six previously reported) suggest a benign clinical behavior for thyroid SFT.

Solitary Fibrous Tumour of Thyroid: Report of Two Cases with Immunohistochemical Features and Literature Review

“…A review of the literature regarding primary thyroid SFT, showed only 19 cases being reported to date ( [7][8][9][10][11][12][13][14][15][16][17] and Table 3). The morphological and immunohistochemical features of SFT of thyroid, including our cases, are identical to pleural-based solitary fibrous tumours.…”

“…With regard to the thyroid gland, only 19 cases have been reported to date [7][8][9][10][11][12][13][14][15][16][17].…”

Intrathoracic Thyroid Solitary Fibrous Tumor Presenting with Respiratory Failure

“…Including the patient described here, only 25 patients have been reported in the English literature. [3][4][5][6][7][8][9][10][11][12][13][14][15][16] The morphologic, immunohistochemical, and ultrastructural features of the thyroid SFTs are similar to their reported counterparts in other anatomic sites and their clinical outcome is similarly benign.…”

Tumor fibroso solitario de la pleura

“…El tumor fibroso solitario se ha informado en múltiples localizaciones de la economía corporal [40][41][42][43][44][45][46][47][48][49][50][51][52][53][54][55] . Estas lesiones tienen las mismas características citogenéticas, morfológicas e inmunohistoquímicas de las observadas en esta neoplasia en la pleura, por lo cual se ha establecido que se trata de la misma lesión 7 .…”

“…Se he reportado en membranas serosas como el peritoneo 40 , ya sea parietal, visceral, retroperitoneo, mesenterio, omento, pared abdominal y sacos herniarios 41 ; también se ha informado en el pericardio, en el cual existen a la fecha 5 casos reportados 42,43 . Otras localizaciones incluyen: meninges, con aproximadamente 30 casos reportados 44 ; cordón espinal, con 12 casos; cavidad oral, con 50 casos 45 ; glándula mamaria, con 50 casos 46 ; tracto gastrointestinal, en el cual se debe hacer su distinción con el tumor estromal gastrointestinal, mediante inmunohistoquímica 47 ; piel, con 10 casos reportados 48 ; riñón, con 20 casos reportados 49 ; tracto genital femenino 50 , y otras 32 localizaciones como órbi-ta, cavidad nasal 51 , espacio pélvico, hígado 52 , mediastino, próstata, glándulas salivales 53 , vías respiratorias superiores, páncreas 54 , corazón, conjuntiva, tiroides 55 , vejiga, amígdalas, vaina carotídea, testículo, entre otros.…”