Abstract: Background and purpose: DR-70 is a fibrin degradation complex, which is a degradation product of plasmin and thrombin released by tumor cells or other tumor-related processes. This article explored its potential application value as a tumor marker for colorectal cancer. Methods: Serum samples were collected from the disease group (215 patients with colorectal cancer) and the control group (30 patients with benign gastrointestinal disease and 440 healthy people) in Fudan University Shanghai Cancer Center, China-Japan Union Hospital of Jilin University, and Tianjin People’s Hospital to determine the cut-off value; combined with the carcinoembryonic antigen (CEA) level, its relation with clinical characteristics of colorectal cancer patient was analyzed. The DR-70 levels of 43 patients with colorectal cancer before and after chemotherapy were followed up. Results: Compared with the control group, the serum DR-70 level of colorectal cancer patient was significantly increased (P<0.05). Under carcinoembryonic (CEA) positive conditions following combined detection of CEA and DR-70, colon cancer was more common when DR-70 was weakly positive, while rectal cancer was more common when DR-70 was strongly positive. When chemotherapy was effective in patients with colorectal cancer, serum DR-70 levels were significantly reduced. Conclusion: Serum DR-70 is a potential marker for the diagnosis of colorectal cancer and can be used as a good indicator for judging the curative effect of postoperative chemotherapy in this type of patient.

Key words: DR-70, Enzyme-linked immunosorbent assay, Colorectal cancer