HDL cholesterol, CRP and lung cancer survival

This study investigated whether common blood tests (such as cholesterol and CRP) could help predict lung cancer survival.

Lung cancer is made up of tumor cells that multiply much faster than normal cells. In order to support this accelerated growth, these cells draw large amounts of blood constituents. Since cholesterol is needed to build cell membranes (the outer shell of the cell), it is hypothesized that more of it will be drawn away from the blood to support tumor growth. Specifically, this process may alter the levels high-density lipoprotein (HDL) cholesterol (also commonly referred to as the "good" cholesterol).

Another important biological process known to affect cancer progression is the appearance of inflammation. Inflammation is an important defense mechanism, but is also known to induce significant damage to different organs. More aggressive cancers are thought to induce a more significant inflammatory response. The intensity of an immune response can be assessed by measuring the levels of C-reactive protein (or CRP) in the blood.

This study assessed whether these blood markers could be used to predict non-small cell lung cancer progression and survival, and any possible association between the two.

The present study included 228 patients diagnosed with non-small cell lung cancer. Blood tests to assess total cholesterol and its components (including HDL and LDL), triglycerides and CRP, were collected before the initiation of cancer treatments.

The study showed that HDL-cholesterol levels were significantly lower among lung cancer patients compared to those in healthy individuals. Among lung cancer patients high levels of HDL-cholesterol independently predicted favorable disease prognosis. 5-year survival rate was 44.1% among patients with low HDL-cholesterol levels, compared to 74.4% in those with normal HDL-cholesterol levels.

HDL-cholesterol levels were also found to be inversely associated with CRP levels. High CRP levels, shown to be a predictor of poor prognosis, consistently correlated to low HDL-cholesterol levels.

This study suggests that simple blood markers, such as HDL-cholesterol and CRP, may help predict lung cancer outcomes.

The significance of these results should be confirmed in larger trials. In addition, both HDL-cholesterol and CRP levels may be affected in many different conditions which were not accounted for in this trial. Whether efforts to elevate HDL-cholesterol levels may also benefit disease prognosis was not investigated.