Lymphangioleiomyomatosis

**Semantic type:** Neoplastic Process

**Definition:** A multifocal neoplasm with perivascular epithelioid cell differentiation affecting almost exclusively females of child-bearing age. It is characterized by the presence of smooth muscle and epithelioid cells and by the proliferation of lymphatic vessels. Sites of involvement include the lungs, mediastinum, and the retroperitoneum. It usually presents with chylous pleural effusion or ascites.

**Synonyms:** - LAM - Lymphangiomyomatosis - Lymphangiomyomatosis