The poor prognosis of adenocarcinoma and adenosquamous carcinoma might be explained by those biological variables still under investigation, such as cyclin-dependent kinase inhibitors, p53, cyclooxygenase-2 (COX-2), cell surface tyrosine-kinases and programmed death-ligand (PD-L1) 24. The gene discussed is PTGS2; the disease is adenocarcinoma.