Prevention of cancer is achieved through the early detection of malignant neoplasms. These growths are known to shed protein antigens at concentrations currently beyond the level of detection of existing bioanalytical methods. Dyne Immune has developed bioanalytical methods that can detect these oligopeptide exogenous antigens in the nanomole to attomole range with linear standard curves, by employing photon counting and conjugated specific antibodies. The linear range of the assay is over 10 orders of magnitude with correlation coefficients of 0.97 or greater.