Epidermal growth factor receptor-binding growth factors in the urine of patients with cancers of the digestive tract

We aimed to assess the diagnostic application of urinary epidermal growth f actor receptor (EGFR)-binding growth factors in cancers of the digestive tr act. By radioreceptor assay and radioimmunoassay, we determined these growt h factors in 115 patients with various cancers of the digestive tract, 30 p atients with benign disease, and 40 healthy controls. The receiver operatin g characteristic (ROC) curve and likelihood ratio were employed to determin e the best diagnostic efficiency. Urinary EGFR-binding growth factors in ea ch cancer group were significantly higher than those in the non-cancer grou ps. Multivariate analysis indicated that the growth factors, determined by both the radioreceptor assay (odds ratio, 1.184; 95% confidence interval, 1 .077-1.302; P = 0.001) and radioimmunoassay (odds ratio, 1.055; 95% confide nce interval, 1.002-1.111: P = 0.039), were associated, in a dose-related f ashion, with the presence of cancers. By ROC curve analysis, the optimal cu toff values for EGFR-binding growth factors were 25.5 mu g/g creatinine (ra dioreceptor assay) and 33.6 mu g/g creatinine (radioimmunoassay). The resul ting sensitivity, specificity, diagnostic accuracy, and positive and negati ve likelihood ratios were 84.4%, 87.5%, 85.2%, 6.75 and 0.18 (for radiorece ptor assay) and 86.1%, 67.5%, 81.3%, 2.64 and 0.21 (for radioimmunoassay), respectively. Except for pancreatic cancer the growth factors showed modera te diagnostic efficiency for the other digestive tract cancers. In conclusi on, urinary EGFR-binding growth factors were increased in cancers of the di gestive tract. They may be used as diagnostic tumor markers.