Title: Risk of Lymph Node Metastasis and Feasibility of Endoscopic Submucosal Dissection
in Undifferentiated-type Early Gastric Cancer
Version: 1 Date: 01 Jan 2023
Reviewer's report:
This study evaluated risk of LNM and feasibility of ESD for UEGC. Although the theme is
interesting, several concerns can be raised.
Major
1. Preoperative and postoperative submucosal invasion are different. Indeed, previous reports
showed that the accuracy of preoperative diagnosis of submucosal invasion is 70-80%. How did
the authors differentiate preoperative submucosal invasion from postoperative one?
2. The same is true in ulceration and tumor size.
3. When the authors differentiated preoperative from postoperative diagnosis, please show the
relationship as a table.
4. Table 3 is important when the three risk factors were evaluated preoperatively. However, the
limitation in this table is a small number of cases. Please add 95% CIs for the proportions of
LNM in each subcategory.
5. Outcome measurement subsection should be included and the detail including the reasons
why candidate variables were selected should be explained in the Methods section. The authors
evaluated many analyses, such as 1) preoperative risk factors for LNM, 2) postoperative risk
factors for LNM, 3) the combination of preoperative (?) factors for predicting LNM, and 4) risk
factors for exceeding the expanded indication. However, it is sometimes difficult to understand
why some candidate variables were selected in the analyses, especially in 4).
6. Please add the status of lymphovascular invasion in Table 4.
7. SM1 (tumor invasion into submucosa <500 µm) and SM2 (tumor invasion into submucosa
#500 µm) are important for LNM, according to the Japanese guidelines. Please divide SM into
SM1 and SM2 in the postoperative analysis of Table 2.
8. The authors concluded that depressed type is at high risk for exceeding the expanded
indication, but flat type also had a significant risk for exceeding the expanded indication. Please
improve the results and conclusion including the abstract.
9. Although the authors suggested that preoperative evaluation should be cautious when the
lesion is depressed (maybe flat type should be included), most UEGCs are flat or depressed type.
In this study, about 94% (325/346) of UEGCs were flat or depressed type. In a prior multicenter
prospective study (Gastric Cancer. 2021; 24: 479-91.), 99% of UEGCs were flat or depressed
type.
Minor
1. Lines 138: Please change “<2 cm” into “#2 cm.”
2. Lines 169: Please change “<1 cm” into “#1 cm.”
Title: Risk of Lymph Node Metastasis and Feasibility of Endoscopic Submucosal Dissection
in Undifferentiated-type Early Gastric Cancer
Version: 1 Date: 01 Jan 2023
Reviewer's report:
This study evaluated risk of LNM and feasibility of ESD for UEGC. Although the theme is
interesting, several concerns can be raised.
Major
1. Preoperative and postoperative submucosal invasion are different. Indeed, previous reports
showed that the accuracy of preoperative diagnosis of submucosal invasion is 70-80%. How did
the authors differentiate preoperative submucosal invasion from postoperative one?
2. The same is true in ulceration and tumor size.
3. When the authors differentiated preoperative from postoperative diagnosis, please show the
relationship as a table.
4. Table 3 is important when the three risk factors were evaluated preoperatively. However, the
limitation in this table is a small number of cases. Please add 95% CIs for the proportions of
LNM in each subcategory.
5. Outcome measurement subsection should be included and the detail including the reasons
why candidate variables were selected should be explained in the Methods section. The authors
evaluated many analyses, such as 1) preoperative risk factors for LNM, 2) postoperative risk
factors for LNM, 3) the combination of preoperative (?) factors for predicting LNM, and 4) risk
factors for exceeding the expanded indication. However, it is sometimes difficult to understand
why some candidate variables were selected in the analyses, especially in 4).
6. Please add the status of lymphovascular invasion in Table 4.
7. SM1 (tumor invasion into submucosa <500 µm) and SM2 (tumor invasion into submucosa
#500 µm) are important for LNM, according to the Japanese guidelines. Please divide SM into
SM1 and SM2 in the postoperative analysis of Table 2.
8. The authors concluded that depressed type is at high risk for exceeding the expanded
indication, but flat type also had a significant risk for exceeding the expanded indication. Please
improve the results and conclusion including the abstract.
9. Although the authors suggested that preoperative evaluation should be cautious when the
lesion is depressed (maybe flat type should be included), most UEGCs are flat or depressed type.
In this study, about 94% (325/346) of UEGCs were flat or depressed type. In a prior multicenter
prospective study (Gastric Cancer. 2021; 24: 479-91.), 99% of UEGCs were flat or depressed
type.
Minor
1. Lines 138: Please change “<2 cm” into “#2 cm.”
2. Lines 169: Please change “<1 cm” into “#1 cm.”
Please review this paper.
user
Title: Risk of Lymph Node Metastasis and Feasibility of Endoscopic Submucosal Dissection
in Undifferentiated-type Early Gastric Cancer
Version: 1 Date: 01 Jan 2023
Reviewer's report:
This study evaluated risk of LNM and feasibility of ESD for UEGC. Although the theme is
interesting, several concerns can be raised.
Major
1. Preoperative and postoperative submucosal invasion are different. Indeed, previous reports
showed that the accuracy of preoperative diagnosis of submucosal invasion is 70-80%. How did
the authors differentiate preoperative submucosal invasion from postoperative one?
2. The same is true in ulceration and tumor size.
3. When the authors differentiated preoperative from postoperative diagnosis, please show the
relationship as a table.
4. Table 3 is important when the three risk factors were evaluated preoperatively. However, the
limitation in this table is a small number of cases. Please add 95% CIs for the proportions of
LNM in each subcategory.
5. Outcome measurement subsection should be included and the detail including the reasons
why candidate variables were selected should be explained in the Methods section. The authors
evaluated many analyses, such as 1) preoperative risk factors for LNM, 2) postoperative risk
factors for LNM, 3) the combination of preoperative (?) factors for predicting LNM, and 4) risk
factors for exceeding the expanded indication. However, it is sometimes difficult to understand
why some candidate variables were selected in the analyses, especially in 4).
6. Please add the status of lymphovascular invasion in Table 4.
7. SM1 (tumor invasion into submucosa <500 µm) and SM2 (tumor invasion into submucosa
#500 µm) are important for LNM, according to the Japanese guidelines. Please divide SM into
SM1 and SM2 in the postoperative analysis of Table 2.
8. The authors concluded that depressed type is at high risk for exceeding the expanded
indication, but flat type also had a significant risk for exceeding the expanded indication. Please
improve the results and conclusion including the abstract.
9. Although the authors suggested that preoperative evaluation should be cautious when the
lesion is depressed (maybe flat type should be included), most UEGCs are flat or depressed type.
In this study, about 94% (325/346) of UEGCs were flat or depressed type. In a prior multicenter
prospective study (Gastric Cancer. 2021; 24: 479-91.), 99% of UEGCs were flat or depressed
type.
Minor
1. Lines 138: Please change “<2 cm” into “#2 cm.”
2. Lines 169: Please change “<1 cm” into “#1 cm.”
assistant