Diagnostic value of measurement of serum type I procollagen carboxy terminal peptides in patients with scirrhous carcinoma of the stomach.

We have evaluated the radioimmunoassay for type I procollagen carboxy terminal peptide (type I C-peptide), which is liberated from type I procollagen during its conversion to collagen, in the serodiagnosis of scirrhous carcinoma of the stomach. The mean (SD) serum concentration of type I C-peptide in 39 normal subjects was 41.7 (19.7) ng/ml. The mean serum values and the positive ratio of type I C-peptide in 11 patients with stages II and III scirrhous carcinoma of the stomach were 91.2 (41.9) ng/ml and 54.5%, respectively. In 10 patients with other types of gastric carcinoma, the mean type I C-peptide values were not significantly different from the normal value. Serum type I C-peptide values reflected the clinical course of scirrhous gastric carcinoma in five patients who underwent either operation or chemotherapy. The measurement of serum type I C-peptide concentrations could provide a useful way of diagnosing and monitoring scirrhous carcinoma of the stomach.