Table of Contents
Definition / general | Case reports | Treatment | Gross description | Gross images | Microscopic (histologic) description | Microscopic (histologic) images | Positive stains | Negative stains | Differential diagnosisCite this page: Pernick N. Solitary fibrous tumor. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/pleurasolitaryfibrous.html. Accessed January 22nd, 2021.
Definition / general
- Also called localized fibrous tumor
- Formerly called benign or solitary fibrous mesothelioma
- Confined to surface of lung, usually does not produce a pleural effusion
- Associated with pulmonary osteoarthropathy, digital clubbing and hypoglycemia, which regress after tumor resection
- Most likely fibroblastic and not mesothelial in origin, arising from submesothelial mesenchyme
- Not associated with asbestos
- May recur locally
- May cause death due to extensive intrathoracic growth or if malignant
- Malignant cases are very rare
Case reports
- 66 year old man with pleural tumor exhibiting liposarcomatous differentiation (Arch Pathol Lab Med 2001;125:406)
- 85 year old woman with 6 cm pleural mass (Case #358)
Treatment
- Surgical excision
Gross description
- Arises from pleural surface by a pedicle
- Solitary, well circumscribed, may be encapsulated
- Composed of dense, gray-white fibrous tissue with firm, whorled cut surface (like uterine leiomyoma), large tumors may be cystic and hemorrhagic
Microscopic (histologic) description
- Fibroblast-like cells with variable cellularity in collagenous, keloid-like stroma, reticulin fibers, hemangiopericytoma-like vessels
- No / rare mitotic activity, no atypia
- May entrap mesothelium or epithelium at periphery
- May have focal or marked myxoid change with bland spindle cells in myxoid, vascularized stroma (Mod Pathol 1999;12:463)
- Malignant cases show increased cellularity, marked nuclear atypia, prominent necrosis, high mitotic activity
Microscopic (histologic) images
Negative stains
Differential diagnosis
- Fibrosarcoma
- MPNST
- Sarcomatoid / desmoplastic mesothelioma: diffuse on Xray, infiltrative, often atypia or mitotic figures
- Spindle cell carcinomas