Prognosis of colorectal cancer patients with elevated endothelin-1 concentrations

Prognostic indicators from clinical, laboratory and pathological data of patients with colorectal cancer are essential to identify high-risk groups in whom adjuvant therapy could be beneficial. Endothelin-1 (ET-1), a growth factor, has been associated with the development and spread fo solid tumours. This prospective study was performed to determine whiter preoperative plasma big ET-1 concentrations might be useful as a prognostic indicator in patients with colorectal carcinoma.

Overall, 65 consecutive patients with colorectal cancer confirmed by biopsy were include prospectively in this study from 1998 to 2001. Plasma samples from a peripheral vein were obtained prior to surgery. Univariant analysis of survival used age (less than or more than 70 years), gender, Dukes' stage (A/B vs C), tumour size (less than or more than 50 mm), vascular invasion, and plasma big ET-1 concentrations, and significant factors were then analysed using a Cox regression model.

Three variables, age, Dukes' tumour stage and plasma big ET-1 concentration, and prognostic significance (p < 0.05). Factors associated with a poorer prognosis were age more than 70 years (p = 0.02), Dukes' C (p = 0.04) and plasma big ET-1 concentration more than 4.2 pg/mL (p = 0.02). The Cox regression model identified the same three variables as having independent prognostic value for overall survival.

Preoperative plasma big ET-1 concentration may be useful in predicting overall survival in patients with colorectal cancer. Plasma big ET-1 concentrations may be useful in the selection of high-risk, lymph node-negative patients with colorectal cancer for adjuvant therapy.