Shinichiro Makimoto, Tomoya Takami, Kotaro Hatano, Naoki Kataoka, Tomoyuki Yamaguchi, Masafumi Tomita, Yoshiharu Shono. Kishiwada Tokushukai Hospital
Purpose: Endoscopic submucosal dissection (ESD) permits en bloc resection of tumors and is particularly indicated for early cancers. The use of ESD has gradually spread with the development of devices for treatment of early colorectal cancer. Therefore, the number of patients undergoing additional surgery after colorectal ESD is increasing.
Patients and Methods: We retrospectively analyzed various clinicopathological features in 53 patients who underwent additional surgery at our hospital among 1,018 patients resected by colorectal ESD in the digestive department of our hospital between February 2010 and July 2018. Additional surgery was judged according to the Japanese Society for Cancer of the Colon and Rectum Guidelines for Treatment of Colorectal Cancer by pathological examination. We excluded patients with ESD discontinuation and patients with perforation caused by ESD.
Results: The mean age of patients was 68.2 years (24 men and 29 women). The average tumor diameter was 30.5 mm. The submucosal invasion depth was ≥1,000 μm in 50 patients and <1,000 μm in three patients. Sixteen patients were positive for vascular invasion (six patients were positive for both lymphatic invasion and venous invasion). Fifteen patients were positive for deep cut margin. Eleven patients had grade 2/3 tumor budding. Muconodules at the site of the deepest invasion were observed in four patients. Histological type was well-differentiated adenocarcinoma in 47 patients, moderately differentiated in four patients, and papillary in two patients. As an additional surgery, 49 laparoscopic colorectal surgeries and 4 laparotomy colorectal surgeries were performed, and one patient underwent hepatectomy simultaneously. Tumor remnant was observed in resected specimens from 2 of 15 deep cut margin positive patients. Lymph node metastasis was confirmed in 8 patients, in 4 of 16 patients with positive vascular invasion, and 4 of 37 patients with negative vascular invasion. Liver metastasis was confirmed in one patient. Furthermore, lymph node metastasis was confirmed in 4 of 11 patients with recognized tumor budding grade 2/3 and 1 of 4 patients with muconodules at the site of deepest invasion.
Conclusion: Positive vascular invasion, tumor budding grade 2/3, and muconodules at the site of deepest invasion were suggested as risk factors for regional lymph node metastasis by T1 colorectal cancer. Proper lymph node dissection and careful attention to the risk of distant metastasis at the time of additional surgery after colorectal ESD are necessary.
Presented at the SAGES 2017 Annual Meeting in Houston, TX.
Abstract ID: 93550
Program Number: S128
Presentation Session: Colorectal III
Presentation Type: Podium