IGICS

Welcome address

Diagnosis and Management of T1 Colorectal Cancer: Revisiting the Role of Deep Submucosal Invasion

Accurate endoscopic diagnosis is fundamental to the optimal management of T1 colorectal cancer (CRC). Established classification systems, including the International Endoscopic Classification Japan NBI Expert Team (IEE-JNET) classification and pit pattern analysis, together with the biological concept of laterally spreading tumors (LST), play a critical role in predicting invasion depth and guiding therapeutic strategies. Recent international consensus statements have further emphasized the importance of integrating high-quality endoscopic diagnosis with histopathological risk stratification in determining appropriate treatment.

Despite advances in diagnostic precision, the management of T1 CRC with deep submucosal invasion remains controversial. Recent Western meta-analyses have suggested that deep submucosal invasion alone may not independently predict lymph node metastasis (LNM), raising the possibility that additional surgery could be avoided in selected cases. However, emerging nationwide datasets demonstrate that invasion depth, particularly ≥2000μm, remains a clinically relevant predictor when evaluated within comprehensive risk models. Furthermore, prospective multicenter cohort data from Japan indicate that even in so-called low-risk T1 CRC, where deep submucosal invasion is the sole high-risk feature, the incidence of LNM approaches 10%, with documented distant recurrence and cancer-related mortality.

This symposium will serve as a global platform to advance scientific discussion on T1 colorectal cancer. We strongly encourage the submission of high-quality abstracts on this theme, particularly from young investigators and emerging leaders across Asia and Japan. Outstanding presentations will be recognized with prestigious awards and financial prizes, aiming to foster academic excellence and support the next generation of leaders in gastrointestinal endoscopy.

1. Saito Y, Sakamoto T, Dekker E, et al. First report from the International Evaluation of Endoscopic Classification Japan NBI Expert Team (IEE-JNET): International multicenter web-based study. Dig Endosc.
2. Zwager LW, Bastiaansen BAJ, Montazeri NSM, et al. Deep submucosal invasion is not an independent risk factor for lymph node metastasis in T1 colorectal cancer: A meta-analysis. Gastroenterology. 2022
3. Kajiwara Y, Oka S, Tanaka S, et al. Nomogram as a predictive tool for lymph node metastasis in T1 colorectal cancer after endoscopic resection. Gastrointest Endosc. 2023
4. Tsuji S, Doyama H, Kobayashi N, et al. Outcomes of noncurative endoscopic submucosal dissection for T1 colorectal cancer: Prospective multicenter cohort study. Dig Endosc. 2024
5. Tanaka S, Kashida H, Saito Y, et al. JGES guidelines for colorectal endoscopic submucosal dissection and mucosal resection. Dig Endosc. 2020

General Information

Theme: Treatment strategy for T1 colorectal cancer
Date：February 13 (Sat.), 2027
Venue：Osaka International Convention Center
5-3-51 Nakanoshima, Kita-ku, Osaka City, Osaka Prefecture, 530-0005
Access：https://www.gco.co.jp/visitor/access/

Call for Abstracts

We are currently preparing for the release.