The aim of this study was to determine the expression of growth hormone receptor(GHR) in patients with pri-mary gastric adenocarcinoma.We investigated 48 specimens of primary gastric adenocarcinoma and their cor-responding normal gastric mucosa.Immunohistochemistry and reverse transcription-polymerase chain reaction(RT-PCR) were used to detect the expression of GHR.Immunohistochemical analyses revealed that GHR was expressed in human primary gastric adenocarcinoma(36/48,75.0%) and appeared to be upregulated,compared to the normal mucosa(28/48,58.3%,P < 0.001).A significant correlation was found between GHR expression and tumor stage(P < 0.001) and tumor differentiation(P < 0.001).The average positive rate of ki-67 in GHR-positive tumors was 16.06%,while the positive rate in GHR-negative tumors was 6.17%(P < 0.01).The average apoptosis index(AI) of GHR-positive tumors was 3.36%,which was significantly lower than that(7.33%) of GHR-negative tumors.In addition,27 of 48 cases of tumors had GHR mRNA expression,while only 17 of all 48 cases of normal mucosa did so.Our results indicate that the frequency of GHR was significantly higher in primary gastric adeno-carcinoma than that in normal gastric mucosa.GHR expression was significantly correlated with tumor differen-tiation and tumor grade.This finding supported a possible role of growth hormone in primary gastric adenocarci-noma pathophysiology. The aim of this study was to determine the expression of growth hormone receptor (GHR) in patients with pri-mary gastric adenocarcinoma. We investigated 48 specimens of primary gastric adenocarcinoma and their cor-responding normal gastric mucosa. Immunohistochemistry and reverse transcription-polymerase chain (RT-PCR) were used to detect the expression of GHR. Immunohistochemical analysis revealed that GHR was expressed in human primary gastric adenocarcinoma (36/48, 75.0%) and had to be upregulated, compared to the normal mucosa (28/48 , 58.3%, P <0.001) .A significant correlation was found between GHR expression and tumor stages (P <0.001) and tumor differentiation (P <0.001) .The average positive rate of ki- , while the positive rate in GHR-negative tumors was 6.17% (P <0.01) .The average apoptosis index (AI) of GHR-positive tumors was 3.36%, which was significantly lower than that (7.33%) of GHR-negative tumors .In addition, 27 of 48 cases of tumors had GHR mRNA expression, while only 17 of all 48 cases of normal mucosa did so. Our results indicate that the frequency of GHR was significantly higher in primary gastric adeno-carcinoma than that in normal gastric mucosa. GHR expression was significantly correlated with tumor differen- tiation and tumor grade. This finding supported a possible role of growth hormone in primary gastric adenocarci-noma pathophysiology.