Clinical studies of type-I procollagen carboxyterminal peptide in serum of patients with gastric cancer: comparison with CEA and CA19-9.

The serum level of a newly developed monoclonal antibody against type-I procollagen carboxyterminal peptide (P-1-P) was determined in patients with gastric cancer. The location of P-1-P in gastric cancer tissue was also investigated. We found that: (1) The serum P-1-P level and the positivity rate in patients with gastric cancer were similar to those in patients with other malignant or benign GI diseases and healthy individuals. (2) In patients with gastric cancer, the P-1-P positivity rate was significantly lower than that of CEA or CA19-9. (3) In patients with gastric cancer, the P-1-P positivity rate increased as the disease stage advanced. (4) Among patients with gastric cancer, the P-1-P positivity rate was significantly higher in those with scirrhous type than in those with medullary or intermediate type. (5) P-1-P was detected in the cytoplasm of cancer cells. P-1-P staining was stronger in scirrhous type and histologically undifferentiated gastric cancer. These results show that P-1-P can serve as a good marker for scirrhous type gastric cancer. The production of collagen by cancer cells themselves seems to be involved in collagen production in scirrhous type gastric cancer.