Histopathologic uncertainties after colorectal endoscopic submucosal dissection with visible retraction of proper muscle layer

We congratulate Dr. Lafeuille et al. on their high quality E-Video “Histological R0 classification after colorectal endoscopic submucosal dissection: a gold standard with feet of clay” [1]. The quality of the images and the short video clip of the endoscopic submucosal dissection (ESD) with rubber band countertraction show the top endoscopic standards at the Edouard Herriot Hospital, Lyon.

Nevertheless, the publication raises concern about the indication for ESD in this case. The text, images, and the short video classify the 4-cm granular laterally spreading tumor (LST), with a 1-cm depression that is Kudo Vn, Sano 3b (0-IIa + c), in the descending colon as a Japan NBI Expert Team (JNET) type 3 lesion, predicting deep submucosal (pT1b sm > 1000 μm) or even proper muscle invasion (pT2) with 96 % accuracy [2] [3]. JNET type 3 lesions (pT1b, sm > 1) have a 5 %–10 % risk of metastatic or recurrent disease after R0 resection, are “out-of-indication for ESD” and, a priori, an indication for laparoscopic surgery and lymphadenectomy in standard locations such as the descending colon in normal risk surgical candidates [3] [4]. We agree that clinical examination should take precedence – artificial intelligence is still not ready to replace the expert endoscopist [5]. Even during ESD done with diagnostic intent, visible invasion of the proper muscle layer (the “muscle retracting sign”) is an indication for delayed surgery rather than intramuscular transection, and then a complete specimen of partial colectomy is appropriate for evaluation of curative resection. We propose that ESD of early gastrointestinal cancers, with curative resection rates of 65 %–75 % in the West, should aim for a professional practice level that includes accurate indications and 80 %–90 % curative ESD rather than expansion of ESD indications that are well established in Japan [3] [6].

Publication History

Article published online:
29 August 2023

• References

• 1 Lafeuille P, Yzet C, Benech N. et al. Histological R0 classification after colorectal endoscopic submucosal dissection: a gold standard with feet of clay. Endoscopy 2022; 54: E798-E799
• 2 Sumimoto K, Tanaka S, Shigita K. et al. Diagnostic performance of Japan NBI Expert Team classification for differentiation among non-invasive, superficially invasive and deeply invasive colorectal neoplasia. Gastrointest Endosc 2017; 86: 700-709
• 3 Hashiguchi Y, Muro K, Saito Y. et al. Japanese Society for Cancer of the Colon and Rectum (JSCCR) guidelines 2019 for the treatment of colorectal cancer. Int J Clin Oncol 2020; 25: 1-42
• 4 Saito Y. Pathologic sm2 carries a moderate risk of metastases even without other unfavorable factors, but positive horizontal margins have a low recurrence risk after en bloc resection. Endoscopy 2023; 55: 252-254
• 5 Yahagi N. Is artificial intelligence ready to replace the expert endoscopists?. Endoscopy 2021; 53: 478-479
• 6 Daoud DC, Suter N, Durand M. et al. Comparing outcomes for endoscopic submucosal dissection between Eastern and Western countries: A systematic review and meta-analysis. World J Gastroenterol 2018; 24: 2518-2536