The relationship between preoperative serum carcinoembryonic antigen (CEA), CA 19-9 and α-fetoprotein (AFP) levels and their clinicopathological features were evaluated in gastric cancer patients. The positive rates of CEA, CA 19-9 and AFP were 24.8, 27.6 and 12.7%, respectively. Gastric cancer with deeper tumor invasion was significantly more common among patients positive for these tumor markers. Patients with positive CEA or CA 19-9 values had a significantly high risk of lymph node metastases (p = 0.045 and p = 0.002, respectively). Synchronous liver metastases was more commonly found in patients with a positive CA 19-9 value. A significant difference (p < 0.001) in survival rate was found between patients with positive CA 19-9 values and those with negative values. CA 19-9 is useful for the prognosis of gastric cancer patients, whereas CEA, although unsuitable for prognosis, contributes to the prediction of cancer invasion.

No abstract

Although peritoneal lavage cytology is widely performed during surgery for gastric cancer and the results have been reported to be one of the accurate prognostic factors, the cancer stage is determined independent of the results of lavage cytology according to the First English Edition of Japanese Classification of Gastric Carcinoma. In this study we demonstrated the validity of lavage cytology for accurately staging gastric cancer. Between 1988 and 1996, peritoneal lavage cytology was performed in 347 patients with resectable gastric cancer. Among them, cytology was positive in 29 cases (8.4%). The survival rate of the cytology-positive patients in each stage was worse than that of all patients in the same stage. The prognosis of patients with positive cytology findings and serosa-exposed gastric cancer was significantly worse than that of negative cytology findings and serosa-exposed gastric cancer, and similar to that of negative cytology findings and serosa-infiltrating gastric cancer. Our data indicated that positive cytology findings thus indicated a poor prognosis, and the prognostic difference between positive and negative cytology findings was approximately a one-stage difference in the Japanese stage grouping. Based on our findings, the results of peritoneal lavage cytology should thus be included in the factors for staging gastric cancer.

Although peritoneal lavage cytology is widely performed during surgery for gastric cancer and the results have been reported to be one of the accurate prognostic factors, the cancer stage is determined independent of the results of lavage cytology according to the First English Edition of Japanese Classification of Gastric Carcinoma. In this study we demonstrated the validity of lavage cytology for accurately staging gastric cancer. Between 1988 and 1996, peritoneal lavage cytology was performed in 347 patients with resectable gastric cancer. Among them, cytology was positive in 29 cases (8.4%). The survival rate of the cytology-positive patients in each stage was worse than that of all patients in the same stage. The prognosis of patients with positive cytology findings and serosa-exposed gastric cancer was significantly worse than that of negative cytology findings and serosa-exposed gastric cancer, and similar to that of negative cytology findings and serosa-infiltrating gastric cancer. Our data indicated that positive cytology findings thus indicated a poor prognosis, and the prognostic difference between positive and negative cytology findings was approximately a one-stage difference in the Japanese stage grouping. Based on our findings, the results of peritoneal lavage cytology should thus be included in the factors for staging gastric cancer.

Autoreactive T-cell clones (Thy 1+, CD4+, CD3+) which suppress generation of cytotoxic T lymphocytes (CTL) were established in long-term in vitro culture by stimulation with GM3-liposomes or soluble melanoma (B16) antigen composed of GM3. The T-cell receptors (TCR) of two representative clones analyzed used the same TCR alpha- and V13+ beta-chains. The clones produce only interferon gamma(IFN-gamma) but not interleukins (IL)2 and 4, despite their CD4+ phenotype, suggesting that they are not a typical TH1 or TH2 type. The clones are effectively stimulated by IFN-gamma treated (I-Ab/GM3+) B16 melanoma or I-Ab-transfected GM3+ L cells, but not by GM3-/I-Ab mutant melanoma, EL 4, or I-Ad/k-transfected L cells. This strongly suggested the involvement of GM3/class II in T-cell recognition. Antigen specificity was required for stimulation of the clones. However, once stimulated, they suppressed CTL generation in an antigen non-specific fashion. As class II+ B16 melanoma cells effectively function as antigen-presenting cells to stimulate the autoreactive suppressor T cell (Ts) clones of this type, this negative circuit between class II+ tumor cells and IFN-gamma-producing Ts would be a possible mechanism whereby tumor cells could escape the immune system.