Lymphangioleiomyomatosis Lymphangioleiomyomatosis (LAM) is a disease of the lungs and lymphatics, which can occur sporadically or in association with tuberous sclerosis complex (TSC). The disease is rare, occurring in 1-2 / million of the population but in up to 40% of women with TSC LAM almost exclusively affects women, generally developing before the menopause. The disease is characterised by progressive pulmonary cystic change, recurrent pneumothorax, chylous pleural collections and, in most cases, progressive respiratory failure. Abdominal manifestations caused by obstruction and dilation of the axial lymphatics include lymphadenopathy, cystic lymphatic masses (lymphangioleiomyomas), chylous ascites and angiomyolipoma (a benign tumour). Survival in LAM is, 70 90% at 10 yrs, although this is highly variable since long-term survivors have been described. Diagnosis is made by a combination of clinical features and computed tomography scanning or, in cases of doubt, lung biopsy. In patients with rapidly progressive disease, hormone treatment (predominantly progesterone) has been used, although no firm evidence supports its use. Otherwise, treatment is aimed at complications including pneumothorax, chylous collections and extra-pulmonary manifestations. The only treatment for severe LAM is currently lung transplantation(Johnson 2006). Recently identification of abnormalities in the tuberous sclerosis complex (TSC) genes in sporadic and TSC associated LAM have identified dysregulation of the mTOR pathway in LAM (Carsillo, Astrinidis et al. 2000; Sato, Seyama et al. 2002) and have lead to clinical trials of mTOR inhibitors such as rapamycin in LAM and TSC. At the time of writing these have not been reported but appear promising.