Lymphangioleiomyomatosis (LAM) is a rare, low-grade, metastasizing neoplasm that arises
from an unknown source, spreads via the lymphatics, and targets the lungs. All pulmonary
structures become infiltrated with benign-appearing spindle and epithelioid cells (LAM cells)
that express smooth-muscle and melanocyte-lineage markers, harbor mTOR-activating
mutations in tuberous sclerosis complex (TSC) genes, and recruit abundant stromal cells.
Elaboration of lymphangiogenic growth factors and matrix remodeling enzymes by LAM …