In addition to abnormal proliferation, smooth muscle-like cells from LAM lungs have increased motility and invasiveness [7], and LAM nodule recurrence was reported after single-lung transplantation in patients without renal angiomyolipoma [8], suggesting a metastatic nature of cells with mutational inactivation of TSC1/TSC2. This evidence concerns the gene TSC1 and lymphangioleiomyomatosis.