To demonstrate the potential clinical utility of ECM-related proteins as lung cancer circulating biomarkers, we analyzed by ELISA assay matched plasma samples from 57 patients (TU) and 57 controls (CTR) for COL11A1 and COL10A1 and from 90 patients (TU) and 90 controls (CTR) for SPARC. The gene discussed is COL11A1; the disease is lung cancer.