Background: We evaluated the influence of several clinicopathologic variables on 5-year actuarial survival rate after curative resection of gastric adenocarcinoma.
Methods: Clinical characteristics were retrieved from the records of all patients who underwent gastric resection for curative intent between 1965 and 1986 at The University of Chicago Medical Center, and follow-up was obtained from our tumor registry. Pathologic characteristics were determined from a detailed review of all available histopathologic slides.
Results: One hundred seventy-eight patients underwent a curative resection during the study period at our institution. Overall 5-year actuarial survival rate was 29%. The relationship between clinicopathologic variables and 5-year survival rate was evaluated by Kaplan-Meier survival curve construction and chi-squared analysis. Lymphatic and/or capillary microinvasion (absent vs present, p < 0.001), tumor location (antrum and body vs gastroesophageal junction, p = 0.05), local extent of disease (limited to the gastric wall versus involving adjacent organs, p = 0.003), stage (absence versus presence of lymph node metastases, p < 0.001), Lauren type (intestinal versus diffuse, p < 0.01), and Ming type (expanding versus infiltrative, p < 0.02) significantly influenced survival. When a multivariate analysis with logistic regression of 5-year survival was performed, lymphatic and/or capillary microinvasion emerged as the only statistically significant, independent prognostic factor associated with long-term survival (p = 0.039). If microinvasion was omitted from the analysis, lymph node metastases (p < 0.05) and the extension to adjacent organs (p < 0.04) became the only statistically significant variables. Multiple correlation analyses suggested that microinvasion is an early histopathologic finding that correlates with a more aggressive natural history.
Conclusions: Lymphatic and/or capillary microinvasion is a more powerful predictor of 5-year survival than lymph node metastases or tumor extension to adjacent organs. Correlation among clinicopathologic variables suggests that microinvasion may represent an early finding, serving as a potential marker for a biologically more aggressive tumor.