Abstract
Background : It is important for us to evaluate the depth of submucosal cancer invasion because there have been reports of significantly increased risk factors for lymph node metastasis of early colorectal cancers in cases where the lesions invaded the deep submucosa (depth of invasion ≧ 1,000 µm : T1b) . The aim of this study is to evaluate diagnostic accuracy in estimating the depth of submucosal invasion of colorectal cancer using both pit pattern and narrow band imaging (NBI) classifications, and to extract endoscopic features for misdiagnosis patients.
Patients and Methods : We enrolled the 522 patients who performed colorectal ESD from January 2,011 to December 2,014. Among them, 283 patients, 286 lesions (57.2%, 162 men, 42.8%, 121 women, Median age ±SD : 66±11.3 years) that we could confirm type VIVI pit pattern were enrolled for this study. We evaluated the ability of differential diagnosis between Tis-T1a (depth of invasion ＜ 1,000 µm) and T1b cancer using type VI pit pattern and NBI, and extract endoscopic features for misdiagnosis patients.
Results : In the relationship between type VI pit pattern and the depth of invasion, sensitivity, specificity, and accuracy were 96.0%, 33.3%, and 88.1%, respectively. On the other hand in the relationship NBI and the depth of invasion, sensitivity, specificity, and accuracy were 89.4%, 32.3%, and 82.5%, respectively. Endoscopic features of misdiagnosis patients of type VI mild were more than 30 mm in max diameter, depressed area, shrunk in size of villous component, constitutive of the focal fold, large nodule, expansiveness, and white spots. For the patients of type VI severe, 5 patients had loss of dyeing and this was the factor of over diagnosis. The remaining 5 patients high frequency of endoscopic features were severe redness, elevation, depressed component, and the area of type VI severe within 5 mm in diameter.
Conclusion : We should utilize the findings of the lesions invaded with deep submucosa in the white light and chromo-endoscopic observation and evaluate submucosal fibrosis of the cancer when we perform ESD.
