Plasma leptin concentrations in male patients with colon carcinoma tended to be elevated compared to male patients with rectal carcinoma (median leptin: 1.7 ng/ml; range: 0.3 – 19.6 ng/ml vs. 0.9 ng/ml; range: 0.3 – 6.7 ng/ml; p=0.070). The gene discussed is LEP; the disease is rectal carcinoma.