PURPOSE: We investigated the clinical impact of HLA-class I tumor cells in gastric cancer. MATERIALS AND METHODS: HLA-class I expression was immunohistochemically evaluated in specimens from 141 gastric cancer patients. The correlation between HLA-class I expression and clinical factors was analyzed. RESULTS: HLA-class I was identified in 96 (68.1%) gastric carcinomas. The loss of HLA-class I significantly correlated with the depth of invasion (P < 0.01), nodal involvement (P < 0.05) and tumor histology (P < 0.01). According to the positivity of HLA-class I, shallow depth and the absence of nodal metastasis increased. HLA-class I expression was a significant prognostic factor in gastric cancer (P < 0.02); however, HLA-class I was not an independent prognostic factor by multivariate analysis. CONCLUSIONS: Our data may suggest that loss of HLA-class I in gastric cancer did not directly reflect immunological escape from tumor antigen-specific cytotoxic T lymphocytes, unlike in other cancers.
PURPOSE: We investigated the clinical impact of HLA-class I tumor cells in gastric cancer. MATERIALS AND METHODS: HLA-class I expression was immunohistochemically evaluated in specimens from 141 gastric cancerpatients. The correlation between HLA-class I expression and clinical factors was analyzed. RESULTS: HLA-class I was identified in 96 (68.1%) gastric carcinomas. The loss of HLA-class I significantly correlated with the depth of invasion (P < 0.01), nodal involvement (P < 0.05) and tumor histology (P < 0.01). According to the positivity of HLA-class I, shallow depth and the absence of nodal metastasis increased. HLA-class I expression was a significant prognostic factor in gastric cancer (P < 0.02); however, HLA-class I was not an independent prognostic factor by multivariate analysis. CONCLUSIONS: Our data may suggest that loss of HLA-class I in gastric cancer did not directly reflect immunological escape from tumor antigen-specific cytotoxic T lymphocytes, unlike in other cancers.