Clinical Significance of Ghrelin Concentration of Plasma and Tumor Tissue in Patients with Gastric Cancer

Abstract

The nutritional status of gastric cancer patients is an important factor determining the outcome after a gastrectomy. Ghrelin is produced primarily in the gastrointestinal tract including the stomach, and has been reported to reflect the nutritional status and control homeostasis by influencing the level of food intake and adiposity. This study examined the difference in the plasma and tissue ghrelin levels according to the clinicopathological features and the extent of a gastric resection in gastric cancer patients who underwent a gastrectomy. Eighty patients over a 3 mo-period were divided into two groups according to the degree of preoperative weight loss (weight loss > or = 5% or < 5%) and the extent of the gastrectomy (subtotal or total gastrectomy). Blood samples were collected from all patients preoperatively and on postoperative day 7. The gastric tissues samples, including the tumor and normal tissues, were obtained from the resected stomach. The ghrelin levels in the plasma and tissue were measured using a commercial enzyme-linked immunosorbent assay kit. There were no significant differences in the clinical characteristics and ghrelin levels in the plasma, gastric tumor tissue, and normal tissue according to the degree of weight loss. There was no correlation between the ghrelin levels in the plasma and tumor tissue. However, the ghrelin level in the tumor tissue was significantly lower than that in the normal tissue. There was an association between the degree of cellular differentiation and ghrelin production. A gastrectomy decreased the plasma ghrelin levels and nutritional index such as the body mass index, triceps skin fold, mid-arm muscle circumference, and biochemical markers regardless of the extent of the gastric resection. Gastric cancer affects the production of ghrelin in the gastric mucosa. Moreover, ghrelin is produced mainly in the stomach even though it might be partially covered by the endogenous ghrelin produced by other organs after gastrectomy. However, more study will be needed to determine if there are other factors that have an impact on energy consumption, ghrelin secretion, and the changes in the ghrelin level after a gastrectomy.