Evaluation of pathologic predictors of
metastases in T1 stage
colorectal cancer may be difficult with
hematoxylin and
eosin (HE) staining alone. The aim of this study was to clarify the role of pathologic predictors by using immunohistochemical staining and
Elastica van Gieson (EVG) staining. One hundred and twenty-four patients who underwent bowel resection for single T1 stage
colorectal cancer from 1990 to 2004 in 1 institution were studied. D2-40, EVG staining, and
CAM5.2 were used to detect lymphatic invasion, venous invasion, and
tumor budding, respectively. These 3 factors were separately evaluated based on HE staining. Histology was reviewed by 1 pathologist.
Lymph node metastases in the surgical specimen were the standard reference, and distant
metastases were identified by periodic computed tomography for 2 years or more after surgery. A logistic regression model was applied to analyze risk factors for
lymph node metastases and a Cox regression model for distant
metastases. In predicting
lymph node metastases, univariate analysis demonstrated significance for all predictors except venous invasion by HE staining. Multivariate analysis showed that venous invasion by EVG and
tumor budding by HE showed significance as predictors. In predicting distant
metastases, univariate analysis showed significance for lymphatic invasion shown by D2-40,
tumor budding shown by
CAM5.2 and HE, and
lymph node metastases. Multivariate analysis showed only venous invasion by EVG
stain as being significantly associated with distant
metastases (P=0.001). In conclusion, venous invasion evaluated shown by EVG staining is a useful pathologic predictor for
metastases in T1 stage
colorectal cancer.