Saliva and plasma TIMP-1 in patients with colorectal cancer:a prospective study

Background and aims. A prospective cross-sectional study was designed to test if total levels of TIMP-1 in saliva and plasma correlated with the diagnosis of colorectal cancer (CRC) in a population with symptoms consistent with this disease. Materials and methods. Stimulated whole saliva and blood samples were collected from 161 individuals referred to colonoscopy with symptoms associated with CRC. The results of the examination, as well as previous and/or current other diseases were recorded. In a blinded study, the authors used an in-house TIMP-1 ELISA previously validated for use in saliva and plasma to determine total levels of TIMP-1. Results. Fifty-six of the patients (35%) were diagnosed with CRC. Plasma TIMP-1 levels were significantly elevated in CRC patients compared with patients with other, non-malignant diseases and individuals without disease. Significant differences in saliva TIMP-1 levels between CRC patients and individuals without CRC could not be demonstrated. In addition, no correlation was found between levels of TIMP-1 in plasma and saliva. Conclusion. Total levels of TIMP-1 in saliva do not reflect the presence of CRC, and TIMP-1 saliva measurements thus cannot substitute plasma TIMP-1 measurements in detection of CRC.