| Abstract: | Aim: In the present study, we aimed to clarify the parameters that can be used for clinically relevant treatment decisions. Patients and methods: During the period from July 1985 to April 2005, 283 pT1 cancers were selected for this study. Risk factors for lymph node (LN) metastasis were evaluated as follows: endoscopic appearance, tumor size, location, lymphatic permeation, venous invasion, patterns of cancer invasion into the submucosal layer, and depth of vertical invasion in the submucosal layer. Results: Results of the logistic regression analysis from these significant parameters were as follows: infiltrating growth pattern (odds ratio: 12.63); lymphatic permeation positive (odds ratio: 5.726); sigmoid colon (odds ratio: 4.585); tumor size (odds ratio: 1.718). However, the leading edge of only one cancer with LN metastasis in the expanding growth group was also cribriform pattern. Conclusion: The invasive growth patterns of infiltrating growth, lymphatic permeation, tumor location of the sigmoid colon, and maximum tumor size were independent and significant risk factors for LN metastasis in our logistic regression analysis. In particular, the former three factors (infiltrating growth, lymphatic permeation and sigmoid colon) revealed high odds ratio and covered all cases of LN metastasis. From the results of our study, the indication for operative intervention after EMR in pT1 cancer is those lesions which possess at least one factor among the three (infiltrating growth, lymphatic permeation and sigmoid colon). Also, assessment of the leading edge with a cribriform pattern should be dealt with carefully. |
