The study also evaluated for other genomic alterations such as Phosphatidylinositol-4,5-Bisphosphate 3-Kinase Catalytic Subunit Alpha (PIK3CA) and potential biomarkers for ESCC such as programmed death ligand-1 (PD-L1) and microsatellite instability/deficient mismatch repair (MSI/dMMR) status in a multivariate analysis, but no statistical correlation could be established due to the low HPV-positive rate in the study. The gene discussed is PIK3CA; the disease is esophageal squamous cell carcinoma.