Squamous cell carcinomas are phenotypically characterized by a hypoxic tumor microenvironment,17, 18, 19 a microenvironmental characteristic associated with radioresistance.45 Squamous cell NSCLCs have a poor vascularization, more often show necrosis, demonstrate GLUT1 and MCT4 expression in a hypoxia‐related pattern, and show a higher rate constant of cytoplasmic phosphorylation of 18F‐FDG and lower blood volume fraction on dynamic 18F‐FDG‐PET.17, 18, 19 This hypoxic tumor microenvironment activates the hypoxia‐inducible factor 1 (HIF‐1) pathway. The gene discussed is HIF1A; the disease is neoplasm.