The association of serum lipid levels with colorectal cancer recurrence.

BACKGROUND:Biologic and epidemiologic evidence suggests that tumor cells depend on reprogrammed lipid metabolic function for survival and growth. Lipids may promote tumor recurrence by providing energy needed for proliferation. Studies have found associations of serum lipids with cancer incidence, mortality, and disease-free mortality, though they have yet to evaluate the prognostic potential of serum lipids for colorectal cancer (CRC) recurrence. METHODS:341 Danish CRC patients who underwent surgical resection were actively followed between 2003-2011 from date of surgery until December 31, 2012, or death. Serum lipids including low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), and triglycerides (TG), were collected at regular intervals. Lipids were assigned as time-varying exposures evaluated with a one-year lag. Cox proportional hazards models were used to assess recurrence rate, adjusting for clinically relevant covariates. A restricted analysis was performed in a group of non-statin users (n = 236). RESULTS:Among 341 CRC patients, increased HDL-C appeared to have a beneficial impact on recurrence-free survival (RFS) for CRC patients, especially among statin users (hazard ratio [HR] for 0.1 mmol/L increase = 0.58; 95 % confidence interval [CI]: 0.43, 0.78). Increased LDL-C and TG were not associated with RFS. Increased lipids showed a near-null effect on CRC recurrence [e.g. HR (95 % CI) for 0.1 mmol/L increase LDL = 1.01 (0.97, 1.19)] among non-statin users. CONCLUSION:Serum lipid levels of LDL-C and TG do not appear to be associated with CRC recurrence. Further investigation of the role of HDL-C in CRC recurrence may be of interest based on the suggestive inverse association observed here.