[Immunohistochemical study on the prognostic value of the expression of laminin and Ki-67 receptors in advanced gastric cancer].

The expression of 67-KDa laminin receptor (LR) was investigated in a group of 75 patients who underwent curative gastrectomy for advanced gastric cancer, with special reference to the possible role in the tumor progression and in the overall survival. In 56 out of these 75 patients also the prognostic significance of proliferative activity was investigated using the monoclonal antibody Ki-67. The tumor LR expression and the Ki-67 labeling index (Ki-67 LI) were immunohistochemically determined in paraffin-embedded sections using the avidin-biotin immunoperoxidase method. The cumulative 5-years survival rate was 75.1% for patients without expression of LR, 52.6% for those with positive LR expression. Significant association between LR expression and depth of tumor invasion (p = 0.022) was found. By univariate analysis the presence of laminin receptor seemed to be associated with an higher risk of death (RR1.73-95% C.I. 0.71-4.20), but this effect disappeared after controlling for depth of tumor invasion. There was no significant relationship between the Ki-67 LI and wall invasion (p = 0.80) or nodal status (p = 0.73). The cumulative 5-year survival rates (95% CI) were 61.0% (35.3-79.2) in patients with Ki-67 index < 10%, 52.4% (29.7-70.9) with Ki-67 index = 10%-40%, 52.9% (27.6-73.0) with Ki-67 index > 40% and the differences were not statistically significant (p = 0.93). Also in multivariate analysis the proliferative activity did not independently affect survival (p = 0.98). An interaction between Ki-67 index and age was found and Ki-67 index > 40% was significantly associated with a poor prognosis in patients over 70 years old old (p = 0.002). In conclusion, tumor expression of laminin receptor could be correlated with gastric cancer aggressiveness, however its prognostic significance is already provided by depth of tumor invasion. The proliferative activity, determined with the monoclonal antibody Ki-67, does not seems to influence the survival except in elderly patients (> or = 70 years old).