RESUMO
BACKGROUND/AIM: Lymphatic and blood vessel invasion are important independent prognostic factors in colorectal cancer, but identification of the separate components remains difficult. The aim of the present study was to compare routine hematoxylin and eosin (H&E) and elastica staining with immunohistochemistry using D2-40 and CD31. MATERIALS AND METHODS: A total of 75 surgical specimens of colorectal cancer were examined for blood and lymphatic vessel invasion, by comparing stains. RESULTS: The minimum clinical follow-up of survivors was 5 years. During that time, 45 patients died, 34 from their cancer. Lymphatic invasion by H&E was found in 19% compared to 40% detected with D2-40 (p<0.001). Lymphatic invasion was not associated with T-stage (H&E, p=0.923; D2-40, p=0.724) but was significantly associated with N-stage, (H&E, p=0.001; D2-40, p<0.001). No significant association between lymphatic invasion (H&E or D2-40) and cancer-specific survival was found on univariate analysis. Blood vessel invasion by elastic detection was detected in 53% compared to 32% detected with CD31 (p=0.090). Blood vessel invasion was associated with T-stage, (elastica, p=0.028; CD31, p=0.839) but was not associated with N-stage (elastica, p=0.377; CD31, p=0.519). On univariate analysis of blood vessel invasion was associated with cancer-specific survival (elastica, p=0.009) when detected by elastica, but not when detected by CD31, (p=0.611). Lymphatic invasion (D2-40) was associated with blood vessel invasion (elastic) (p=0.019). On multivariate analysis, blood vessel invasion with elastica had independent prognostic value (hazard ratio=2.55, 95% confidence interval=1.23-5.28; p=0.012). CONCLUSION: The results of the present study indicate that immunohistochemistry using D2-40 improves the identification of lymphatic invasion compared to use of H&E staining only; however, its prognostic value was limited. Elastica staining improves the detection rate of blood vessel invasion (compared to CD31) and venous invasion detected with elastica had independent prognostic value in patients undergoing curative resection for colorectal cancer.