ENO2 and diabetes mellitus: However, patients with an elevation of tumor markers could be detected malignancies 32 months after the onset of DM: one case of DM with a high level of carcinoembryonic antigen was found to have gastric cancer 16 months later; one case of DM with high levels of CA-211 and neuron–specific enolase was found to have nonsmall cell lung cancer 32 months after the DM diagnosis; another DM patient with a high level of CA-211 was detected to have NSCLC with a brain metastasis in only 2 months.