A new case study from Nishida et al., (2015) reports a BHD patient with multiple pulmonary cysts and an adenocarcinoma in one lung. Her son and both her brothers had a history of pneumothoraces and one brother had also previously had a pulmonary adenocarcinoma removed. Pulmonary tumourigenesis in BHD patients has been previously reported (Gunji et al., 2007, Furuya & Nakatani 2013) and would appear to correlate with a history of smoking. Nishida et al. propose that activation of Akt, resulting from smoking, could be increasing mTOR signalling increasing the risk of tumourigenesis. So far there are no published reports investigating “second-hits” to the remaining FLCN alleles in these pulmonary tumours. Further studies are required to determine if there is a link between mutations in FLCN and pulmonary tumourigenesis, and the impact of smoking on this relationship.