The cancer biomarkers were successfully detected with limits of detection of 6.17 pg/mL for sPD-1, 0.68 pg/mL for sPD-L1, and 69.86 pg/mL for sEGFR, demonstrating the potential of multiplexed SERS detection of soluble cancer protein biomarkers as a cancer diagnostic tool. The gene discussed is SPDL1; the disease is cancer.