Acute-phase plasma proteins in gastric cancer: association with metastatic potential and prognosis

We evaluated the possibility that acute-phase plasma proteins such as alpha 1-antichymotrypsin (ACT) and immunosuppressive acidic protein (IAP) might be useful predictors of lymph node metastasis and prognosis in patients with gastric cancer. Both ACT and IAP levels generally increased according to the pTNM stage. Patients with both abnormal IAP and ACT levels showed a high risk of lymphatic and hepatic metastasis as well as peritoneal dissemination, with a resultant poor prognosis. Patients who had abnormal IAP levels with or without abnormal ACT levels had a significantly higher risk of lymph node metastasis, as well as more invasive tumors and a worse prognosis than those who had normal IAP levels with or without abnormal ACT levels. In combination group 4 [IAP(+) ACT(-) vs. IAP(-) ACT(+)] lymphatic metastasis was seen more often with isolated IAP(+) (76.4%) than with ACT(+) (52.9%) (p < 0.0045), especially in the subgroup of poorly differentiated adenocarcinoma (POR; p < 0.0177). However, this does not demonstrate that ACT(+) is a protective factor against lymphatic invasion, because the results of combination group 6 [IAP(-) ACT(+) vs. IAP(-) ACT(-)] show that isolated ACT(+) is also significantly related to lymphatic metastasis (p < 0.001). The same is true for the subgroup of signet ring cell carcinomas (p = 0.038), but it has not been tested versus the POR subgroup.