Korean J Pathol.
1997 Apr;31(4):351-356.
Malignant Solitary Fibrous Tumor of the Pleura in Mediastinum
- Affiliations
-
- 1Department of Pathology, Inje University, Seoul Paik Hospital, Seoul 100-032, Korea.
- 2Department of Internal Medicine, Inje University, Seoul Paik Hospital, Seoul 100-032, Korea.
- 3Department of Thoracic Surgery, Inje University, Seoul Paik Hospital, Seoul 100-032, Korea.
Abstract
- Solitary fibrous tumors (SFTs) most often involve the pleura and also may encompass the peritoneum and nonserosal sites. They occur as solitary encapsulated tumors and pursue a relatively benign clinical course. The usual criteria for malignancy are high cellularity, mitotic activity (more than 4 per 10 high-power fields), cellular pleomorphism, hemorrhage and necrosis as well as infiltrative growth. We report a case of malignant SFT of pleura who presented with an anterior mediastinal mass. Grossly, it was a 10x8x6.5 cm sized, encapsulated and well-demarcated, solid neoplasm with areas of extensive necrosis. Microscopically, parallel or haphazard arrangement of spindle cells with variable degrees of collagenous background were noted. Storiform fascicle formation, hemangiopericytoma-like pattern, and epithelioid cell clusters were often intermingled. Nodular areas with high cellularity and mitotic activity (> or =10/10 HPFs) were scattered throughout the neoplasm, however no definite cellular pleomorphism was encountered. Tumor cells were immunoreactive for vimentin and CD-34, which distinguished them from the mesothelial cells. Electron microscopically, they revealed fibroblastic and myofibroblastic differentiation.
