Leiomyoma of Deep Soft Tissue, Retroperitoneum, Mesentery and Omentum
Supplemental Studies
Immunohistology
- Smooth muscle actin and muscle specific actin positive
- Desmin or caldesmon positive but may be less extensive than actin
- CD34 occasionally positive, usually weakly
- Keratin and EMA may show occasional, usually patchy or dot-like staining
- S100 has been reported in smooth muscle tumors of various sites
- The combination of actin negative and S100 positive should strongly suggest nerve sheath tumor
