PDGFA and clear cell renal carcinoma: To our knowledge, elevated expression of PDGFA has been observed in various tumor types, such as head and neck squamous cell carcinoma, renal clear cell carcinoma, liver cancer, and lung cancer.[28] Additionally, Klimczak-Bitner et al found that PDGFA exhibited statistically higher expression level in EC tissues than in the corresponding normal samples.[29] As both ESCC and esophageal adenocarcinoma are main histopathological subtypes of EC, the expression of PDGFA in ESCC is still unknown.