Pre-operative plasma CK18-Asp396 and total CK18 levels, and survival. CK18-Asp396 and total CK18 levels in pre-operative plasma of all colorectal cancer patients with a Dukes' A/B vs Dukes' C/D stage carcinoma (P1, A and B). Box plots with line indicating median value, box indicating IQR and bars indicating the range. Kaplan Meier disease-free survival curves of all colorectal cancer patients, groups divided upon median values of CK18-Asp396 (C) and total CK18 levels (D) in pre-operative plasma (P1). Patients were also subdivided in Dukes' A/B (E, n = 22) and Dukes' C/D (F, n = 27) stage carcinoma.