Lung cancer—predominantly non-small cell lung cancer (NSCLC)—is the most prevalent cancer in the world, in terms of both incidence and mortality. Squamous cell lung cancer (SCLC) is the second most common type of NSCLC, making up about 30% of all cases. The average 5-year survival rate among NSCLC patients is barely 15% (Herbst et al., 2008). Among post-surgery patients, prognosis varies widely, even among patients with similar clinicopathological characteristics, demonstrating the need for improved ways to predict treatment outcomes (Chen et al., 2007).