Relationship between statin use and colon cancer recurrence and survival: results from CALGB 89803.

Background: Although preclinical and epidemiological data suggest that statins may have antineoplastic properties, the impact of statin use on patient survival after a curative resection of stage III colon cancer is unknown.
Methods: We conducted a prospective observational study of 842 patients with stage III colon cancer enrolled in a randomized adjuvant chemotherapy trial from April 1999 to May 2001 to investigate the relationship between statin use and survival. Disease-free survival (DFS), recurrence-free survival (RFS), and overall survival (OS) were investigated by Kaplan-Meier curves and log-rank tests in the overall study population and in a subset of patients stratified by KRAS mutation status (n = 394), and Cox proportional hazards regression was used to assess the simultaneous impact of confounding variables. All statistical tests were two-sided.
Results: Among 842 patients, 134 (15.9%) reported statin use after completing adjuvant chemotherapy. DFS among statin users and nonusers was similar (hazard ratio [HR] of cancer recurrence or death = 1.04, 95% confidence interval [CI] = 0.73 to 1.49). RFS and OS were also similar between statin users and nonusers (adjusted HR of cancer recurrence = 1.14, 95% CI = 0.77 to 1.69; adjusted HR of death = 1.15, 95% CI = 0.77 to 1.71). Survival outcomes were similar regardless of increasing duration of statin use before cancer diagnosis (P(trend) = .63, .63, and .59 for DFS, RFS, and OS, respectively). The impact of statin use did not differ by tumor KRAS mutation status, with similar DFS, RFS, and OS for statin use among mutant and wild-type subgroups (P(interaction) = .84, .67, and .98 for DFS, RFS, and OS, respectively).
Conclusion: Statin use during and after adjuvant chemotherapy was not associated with improved DFS, RFS, or OS in patients with stage III colon cancer, regardless of KRAS mutation status.