Change of the growth hormone-insulin-like growth factor-I axis in patients with gastrointestinal cancer: related to tumour type and nutritional status.

Changes in the growth hormone (GH)-insulin-like growth factor-I (IGF-I) axis, especially acquired GH resistance, develop in many severe illnesses, including cachexia. To study changes in the GH-IGF-I axis in patients with cancer cachexia, biochemical markers and body composition parameters were measured in eighty-eight gastric cancer patients, thirty colorectal cancer patients (subclassified according to the presence or absence of cachexia) and twenty-four healthy control subjects. Fifty-nine patients were defined as cachectic, based on the percentage of weight loss compared with their previous normal weight. The remaining fifty-nine patients were defined as non-cachectic. Measurements were repeated in twenty-seven patients (sixteen with gastric cancer and eleven with colorectal cancer) 3 months after radical operation. Compared with the controls, the cachectic gastric cancer patients had high GH levels (1.36 v. 0.32 ng/ml; P=0.001), a trend towards high IGF-I levels (223.74 v. 195.15 ng/ml; P=0.128 compared with non-cachectic patients) and a low log IGF-I/GH ratio (2.55 and 2.66 v. 3.00; P=0.002), along with a decreased BMI; the cachectic colorectal cancer patients showed the biochemical characteristics of acquired GH resistance: high GH (0.71 v. 0.32 ng/ml; P=0.016), a trend towards decreased IGF-I levels (164.18 v. 183.24 ng/ml; P=0.127) and a low log IGF-I/GH ratio (2.54 v. 2.99; P=0.005), with increased IGF-I levels following radical surgery (200.49 v. 141.91 ng/ml; P=0.046). These findings suggest that normal GH reaction and sensitivity occur in gastric cancer patients, controlled by nutritional status, whereas acquired GH resistance develops in cachectic colorectal cancer patients, which may be caused by tumour itself.