Lymphangio-myomatosis : Immunostains

Comments:
The plump myoid cells in lymphangiomyomatosis are positive for HMB-45, melan A, beta-catenin, and smooth muscle actin. Many cases stain for estrogen and progesterone receptors. They are usually negative for S-100 protein.

The image shows lesional spindle-shaped myoid cells around the edges of cystic airspaces.