Primary pulmonary sarcoma, NOS - Case 299

Asymptomatic 87 year old male with a lesion detected in the right lower lobe. Core biopsy performed. Negative immunostains: AE1/AE3, CAM 5.2, SMA, Actin, Desmin, CD34, CD117, BCL-2, S100, CD56, Chromogranin A, HMB45, CD68. Positive immunostains: FLI-1, CD99 (focally +), Ki-67 (focally + <5%).Molecular studies for synovial sarcoma and Ewing's sarcoma were negative. No significant past medical history and no evidence of extrapulmonary involvement. This sarcoma could not be subtyped. Primary pulmonary sarcomas are very rare accounting for approximately 0.2% of primary pulmonary malignant neoplasms. Metastatic sarcomas are seen far more frequently.

Done