PIK3CA and non-small cell lung carcinoma: In the present study, we used quantitative methylation-specific PCR (Q-MSP) to evaluate methylation levels of a panel of cancer-related genes in a cohort of clinically well-characterized NSCLC samples, including CALCA, CDH1, DAPK1, EVX2, PAX6, and RASSF1A, and further explore the association of promoter methylation of these genes with PIK3CA amplification.