Presentation Information
[SY8-1]Re-positioning of Endoscopic Ultrasonography in Determining the Treatment Strategy for Colorectal Cancer Suspected of Submucosal Invasion
*Noriko Matsuura1, Kaoru Takabayashi2, Motohiko Kato2 (1. Division of Research and Development for Minimally Invasive Treatment, Cancer Center, Keio University School of Medicine, Japan, 2. Center for Diagnostic and Therapeutic Endoscopy, Keio University School of Medicine)
＜Background＞
Endoscopic submucosal dissection (ESD) is one of the most precise staging modality of early colorectal cancers. ESD is increasingly performed for lesions suspected of submucosal (SM) invasion; however, the feasibility of curative ESD before treatment has not been fully investigated. Although depth diagnosis is mainly based on white-light and magnifying endoscopy, unexpected muscularis propria invasion is occasionally encountered. Endoscopic ultrasonography (EUS) enables tomographic visualization of the gastrointestinal wall and may therefore be useful for predicting the feasibility of ESD and differentiating T1 from T2 colorectal cancers.
＜Methods＞
We retrospectively investigated the relationship between EUS findings, histopathological depth of invasion, and vertical margin (VM) status in lesions treated with ESD among colorectal lesions suspected of SM invasion between June 2020 and June 2025.
EUS findings were classified according to our previously reported PREDICT classification as follows:
Type I: the third layer (submucosal layer) beneath the lesion was continuously and reproducibly preserved;
Type II: the third layer beneath the lesion was unclear;
Type III: thickening of the fourth layer (muscularis propria).
＜Results＞
Thirty-eight lesions were included in the analysis, including 10 proximal colon, 5 distal colon, and 22 rectal lesions. ESD and surgery were performed in 19 and 19 lesions, respectively. Histopathological depth was pT1a in 10 lesions, pT1b in 20 lesions, and pT2 or deeper in 8 lesions.
According to the PREDICT classification, 19 lesions were classified as Type I, 13 as Type II, and 6 as Type III. The pVM0 rate among the lesions treated with ESD was significantly higher in Type I lesions than in Type II lesions (94% [15/16] vs. 0% [0/3], p<0.01). The proportion of pT2 or deeper cancers was significantly higher in Type II/III lesions than in Type I lesions (47% [9/19] vs. 0%, p<0.01).
<Conclusions>
The PREDICT classification was useful for predicting the feasibility of ESD and differentiating T1 from T2 colorectal cancer.
Endoscopic submucosal dissection (ESD) is one of the most precise staging modality of early colorectal cancers. ESD is increasingly performed for lesions suspected of submucosal (SM) invasion; however, the feasibility of curative ESD before treatment has not been fully investigated. Although depth diagnosis is mainly based on white-light and magnifying endoscopy, unexpected muscularis propria invasion is occasionally encountered. Endoscopic ultrasonography (EUS) enables tomographic visualization of the gastrointestinal wall and may therefore be useful for predicting the feasibility of ESD and differentiating T1 from T2 colorectal cancers.
＜Methods＞
We retrospectively investigated the relationship between EUS findings, histopathological depth of invasion, and vertical margin (VM) status in lesions treated with ESD among colorectal lesions suspected of SM invasion between June 2020 and June 2025.
EUS findings were classified according to our previously reported PREDICT classification as follows:
Type I: the third layer (submucosal layer) beneath the lesion was continuously and reproducibly preserved;
Type II: the third layer beneath the lesion was unclear;
Type III: thickening of the fourth layer (muscularis propria).
＜Results＞
Thirty-eight lesions were included in the analysis, including 10 proximal colon, 5 distal colon, and 22 rectal lesions. ESD and surgery were performed in 19 and 19 lesions, respectively. Histopathological depth was pT1a in 10 lesions, pT1b in 20 lesions, and pT2 or deeper in 8 lesions.
According to the PREDICT classification, 19 lesions were classified as Type I, 13 as Type II, and 6 as Type III. The pVM0 rate among the lesions treated with ESD was significantly higher in Type I lesions than in Type II lesions (94% [15/16] vs. 0% [0/3], p<0.01). The proportion of pT2 or deeper cancers was significantly higher in Type II/III lesions than in Type I lesions (47% [9/19] vs. 0%, p<0.01).
<Conclusions>
The PREDICT classification was useful for predicting the feasibility of ESD and differentiating T1 from T2 colorectal cancer.