HLA‐DR4 antigen and lymph node metastases in poorly differentiated adenocarcinoma of the stomach

Background. The authors investigated whether HLA antigens could act as a predictor of the risk of lymph node metastasis in patients with gastric cancer. Methods. The microcytotoxicity assay was used to examine 51 HLA antigens of the A, B, C, DR, and DQ loci in 573 patients who underwent resection of gastric cancer. The incidence of HLA antigens in patients with or without lymph node metastasis was analyzed using the chi‐square method. Results. The incidence of patients with HLA‐DR4 antigen with or without lymph node metastasis was 45.9% and 34.8%, respectively (P = 0.0098, corrected P = 0.49). The relative risk of lymph node metastasis in patients with HLA‐DR4 was 1.6. In poorly differentiated adenocarcinoma, the incidence of HLA‐DR4 antigen in patients with lymph node metastasis was significantly higher (47.5%) than in patients without lymph node metastasis (18.5%), if corrected P values were tested (P = 0.0007, corrected P = 0.0387). The relative risk of lymph node metastasis in patients with poorly differentiated adenocarcinoma with DR4 was 4.0. Conclusions. The data suggest an association between the presence of HLA‐DR4 and an increased risk of lymph node metastasis, especially in poorly differentiated adenocarcinoma.