The test is based on the discovery that there are cancer-specific transcript variants of ecto-nicotinamide adenine dinucleotide oxidase disulfide-thiol exchanger 2 (ENOX2) [8, 9] and consists of 2-D gel electrophoretic separation of serum proteins followed by immunoblot analysis with an ENOX2-specific recombinant antibody. Here, ENOX2 is linked to cancer.