The grayscale value of positive cells of p-mTOR (mTOR signaling pathway) in Birt–Hogg–Dubé patients was lower than in patients with simple pulmonary bulla (98.000 ± 1.630 vs. 67.800 ± 2.209, Figures 8(g) and 8(h)). This evidence concerns the gene MTOR and Pulmonary bulla.