[Clinical short-term and long-term efficacy of endoscopic submucosal dissection in the treatment of early low rectal cancer and precancerous lesions].

Objective: To evaluate the short-term and long-term efficacy of endoscopic submucosal dissection (ESD) in the treatment of early low rectal cancer and precancerous lesions. Methods: Inclusion criteria: (1) Distance from the lower margin of tumor to the anal was ≤ 5 cm. (2) Early low rectal cancers were any size rectal epithelial tumors with infiltration depth limited to the mucosa and submucosa, which were diagnosed by postoperative pathology as high-grade intraepithelial neoplasia or adenocarcinoma of the rectum with infiltration depth of intramucosal or submucosal cancer (M or SM stage). (3) Precancerous lesions included adenoma and low-grade intraepithelial neoplasia of the rectum. (4) Patients received ESD treatment. Patients with tumor invasion depth over submucosa by pathology were excluded. From January 2008 to January 2018, 63 patients meeting the above criteria in Peking University First Hospital were enrolled in this descriptive cohort study. The disease characteristics, clinical manifestations, pathological types, treatment time, hospitalization time, en bloc resection rate (resection of the whole lesion), complete resection rate (both the horizontal and vertical incision margins were negative), postoperative complications and follow-up results were analyzed. Cummulative survival rate was calculated by Kaplan-Meier. Results: The diameter of the lesion was (29.0±23.4) mm and the distance from the lesion to the anus was (2.7±1.8) cm. The median operation time was 45.0 (range, 10.0 to 360.0) minutes, the median hospitalization time was 3.0 (range, 2.0 to 12.0) days, en bloc resection rate was 100%, complete resection rate was 96.8% (61/63), and 1 case (1.6%) had postoperative bleeding. The follow-up rate was 87.3% (55/63) and the median follow-up time was 57.9 (range, 15.6 to 121.1) months. No local recurrence was found during the follow-up period and the 5-year survival rate was 100%. Conclusion: Short- and long-term efficacy of ESD are quite good in the treatment of patients with early low rectal cancer and precancerous lesions.

Endoscopic ultrasonography assessment for ampullary and bile duct malignancy.

From 1989 through 1992, endoscopic ultrasonography (EUS) was undertaken preoperatively to evaluate the extent of primary tumor, involvement of regional lymph nodes, and distant metastases in 22 patients with ampullary carcinoma and 18 patients with bile duct carcinoma. The results were compared with histopathological findings according to the TNM staging system. The accurate rate in assessing the extent of cancer invasion was 82% for ampullary carcinoma, 66% for common hepatic duct carcinoma, and 78% for common bile duct carcinoma. The accuracy of EUS in predicting regional lymph node metastasis was 59% for ampullary carcinoma, 56% for common hepatic duct carcinoma, and 67% for common bile duct carcinoma. Invasion of the portal vein was correctly predicted by EUS in 2 of 3 patients. None of the 3 patients with liver metastasis was detected by EUS. Therefore, endoscopic ultrasonography is an effective method in the evaluation of the extent of cancer invasion of ampullary and bile duct carcinoma as well as the involvement of regional lymph nodes preoperatively. However, due to its limited penetration depth, EUS is inadequate in the assessment of liver metastasis.