Based on the upregulation of SSAT-1 in different types of cancer, we developed a customized assay to help explore whether (1) the concentrations of polyamine and other endogenous metabolites comprised of amino acids, biogenic amines, acylcarnitines and glycerophospholipids in serum of lung cancer patients could be used as a diagnostic test for lung cancer and (2) evaluate whether combining a panel of these new metabolites can further enhance and complement the SSAT1 amantadine assay performance for detection of lung cancers [32]. Here, SAT1 is linked to cancer.