Resistance to activated protein C, factor V leiden and the prothrombin G20210A variant in patients with colorectal cancer.

Objective: The aim of our study was to determine the frequency of resistance to activated protein C (APC), factor V Leiden (FVL) and the prothrombin G20210A variant in patients with colorectal cancer.

Methods: 74 patients with colorectal cancer and 192 colonoscopically selected controls were prospectively investigated for the presence of APC resistance, FVL and the prothrombin G20210A variant. APC resistance was measured as the ratio of activated partial thromboplastin times with and without APC (APC sensitivity ratio, APC-SR).