Intramedullary solitary fibrous tumor of dorsal spinal cord

Abstract

Solitary fibrous tumors (SFT) are rare neoplasms of mesenchymal origin involving soft tissues, mainly serosal sites; the spinal cord location is uncommon. We report a case of SFT occurring in the thoracic spinal cord, discussing histological, ultrastructural and molecular aspects. A 75-year-old woman with an MRI suggesting a dorsal intracanalar lesion was admitted to our institution. T5-T7 laminectomies were performed and an intramedullary tumor was discovered. The tumor arose within the spinal cord and was completely removed. Tumor samples were processed for histological, ultrastructural and molecular analysis (comparative genomic hybridization [CGH], methylation status of O6-methylguanine-DNA methyltransferase [MGMT], p16, deleted in colorectal cancer [DCC] and death-associated protein kinase 1 [DAPK1]). The histological examination demonstrated a proliferation of spindle-shaped cells with a collagen-matrix background. Immunohistochemical staining was positive for vimentin and CD34 and negative for S-100 and epithelial membrane antigen. A histological diagnosis of SFT was made. The ultrastructural examination showed undifferentiated cells within a collagenous matrix and sparse extravascular basement membrane. CGH analysis revealed deletion of 9p21 and losses on 2q, 3p, 16q and 19q and gains on 7q; furthermore, no aberrant methylation pattern was found in the promoter region of MGMT, p16, DCC and DAPK1 genes. On the second-year follow-up, the patient was neurologically intact. The occurrence of SFT within the spinal cord parenchyma and its histological characteristics demonstrate that SFTs are not restricted to serosal surfaces. The course of spinal cord SFT is unknown and long-term follow-up is necessary. The histological, ultrastructural and molecular findings are important for the diagnosis and the authors provide a literature review of these aspects.

Intramedullary Solitary Fibrous Tumor—A Benign Form of Hemangiopericytoma? Case Report and Review of the Literature

“…However, intramedullary SFTs are still a rare entity. To the best of our knowledge, only 17 cases including the present one have been published so far (1,4,8,10,11,17,18,20,21,27,29,33,34,38).…”

“…Nevertheless, SFTs can arise in the soft tissue anywhere in the body, even in the central nervous system (2,7,8,15,18,21,24,32,(41)(42)(43). The occurrence completely or partially within the spinal cord is rare and has been reported in 16 cases so far to the best of our knowledge (1,4,8,10,11,17,18,20,21,27,29,33,34,38).…”

“…However, the histological findings of SFT show many similarities to the more malignant hemangiopericytoma (HPC), which is also rare in the central nervous system (5,10,36,38). In the past decade more and more pathologists assume a common spectrum of these tumors (5,28).…”

Intramedullary spinal cord solitary fibrous tumor: A rare clinical entity

“…There have been only 14 reported cases of intramedullary SFTs [2,[4][5][6][7][8][9][10][11][12]. These patients had various presenting symptoms with most experiencing gradually progressive weakness and paresthesias associated with myelopathy, but normal bowel and bladder function and normal perineal sensation.…”

Hemorrhagic intramedullary solitary fibrous tumor of the conus medullaris: case report

“…6,21,34 Specifically, within the spine there have been 46 reported cases 1,4,5,7,8,[10][11][12][13][14][15][16][17][18][19][20]22,23,[25][26][27][28][29][30][31][32][33][35][36][37] in the literature since the first description in 1997. …”