Fig. 1: Detecting tumour immunosurveillance for diagnostics.

a A patient with a breast tumour provides a 5 mL whole blood sample. b The c. 70 mg/mL protein component plays roles in immunosurveillance, in which the immune system identifies and eliminates malignant cells. This process increases in early-stage cancer before cancer immunoediting allows immune escape and metastasis. It is also the target of immunosurveillance increasing drugs, such as immune checkpoint inhibitors (ICI’s) and a recently discovered additional mechanism of Cyclin-dependent kinase inhibitors (CDKi’s)³⁶. c Example of immune surveillance enhancement observed upon development of prostate cancer¹². d The host immune response includes up to 3000 additional proteins¹⁶, however, clinically meaningful quantification remains challenging due to high intra and inter-individual variation. e We introduce the concept of taking an average across all individual protein targets. This Amino Acid Concentration Signature (AACS) provides a protein cross-section, which reduces intra and inter-individual variation via the Law of Large Numbers.