Title: Importance of preoperative total colonoscopy and endoscopic resection after self-
expandable metallic stent placement for obstructive colorectal cancer as a bridge-to-surgery
Version: 3 Date: 18 May 2023
Reviewer's report:
Dear Editors,
thank you very much for letting me review this interesting paper.
The authors show their experience in 100 patients treated with SEMS placement for obstructive
colon cancer and the findings observed at pre-operative total colonoscopy enabled by SEMS
placement.  Preoperative total colonoscopy was performed in 86/100 patients. In 47 patients
a total of 143 lesions were endoscopically resected, including 9 non advanced synchronous
cancers. Additionally 4 advanced synchronous colon cancer were found at preoperative
colonoscopy.
International guidelines do not specifically recommend total colonoscopy prior to colonic
resection for obstructive cancer after SEMS placement. Therefore, it is interesting to see
the findings the authors made and might have changed the operative management of the
patients. Additionally, the findings by the authors shed some light on feasibility of preoperative
colonoscopy and feasibility of trans- stent endoscopic resection methods (CSP/EMR/ESD).
I would accept it for publication, but have some questions/remarks:
1. Did all patients undergo complete CT scans of the oncologic disease prior to colonoscopy and
if so: how many of the advanced/non advanced synchronous cancer were already detectable?
2. What is the conclusion by the authors concerning the decision made by the surgeon: Did
preoperative colonoscopy change the decision for colon resection? In how many cases were the
synchronous tumors next to the obstruction and in how many cases distant to the obstruction?
3. Which definition did you use for advanced / non advanced colon cancer
4. Is it possible including the preoperative UICC tumor stadium for all patients? It is not clear
if some patients were resected in a palliative manner or only curative intent.
5. Please provide patient data (gender, age, etc.)
6. 86/98 patients with total colonoscopy after SEMS placement. Why did 12 patients not undergo
colonoscopy?
7. Figure 1 box “TCS”: patients
8. Table 3: Is it possible to declare what kind of cancerous lesions were present (Paris
classification?)
9. Table 3: number of total synchronous cancer (lesion/patient): should be 13/12 and not 13/11?
10. It would also be helpful to declare the Boston Bowel Preparation score in patients which
had TCS after SEMS placement. This could help understand the rate of remaining lesions
encountered 1 year after colonic resection on follow up endoscopy.
11. Please declare if the data was retrospectively analyzed or prospectively collected.
Kind regards.
Title: Importance of preoperative total colonoscopy and endoscopic resection after self-
expandable metallic stent placement for obstructive colorectal cancer as a bridge-to-surgery
Version: 3 Date: 18 May 2023
Reviewer's report:
Dear Editors,
thank you very much for letting me review this interesting paper.
The authors show their experience in 100 patients treated with SEMS placement for obstructive
colon cancer and the findings observed at pre-operative total colonoscopy enabled by SEMS
placement.  Preoperative total colonoscopy was performed in 86/100 patients. In 47 patients
a total of 143 lesions were endoscopically resected, including 9 non advanced synchronous
cancers. Additionally 4 advanced synchronous colon cancer were found at preoperative
colonoscopy.
International guidelines do not specifically recommend total colonoscopy prior to colonic
resection for obstructive cancer after SEMS placement. Therefore, it is interesting to see
the findings the authors made and might have changed the operative management of the
patients. Additionally, the findings by the authors shed some light on feasibility of preoperative
colonoscopy and feasibility of trans- stent endoscopic resection methods (CSP/EMR/ESD).
I would accept it for publication, but have some questions/remarks:
1. Did all patients undergo complete CT scans of the oncologic disease prior to colonoscopy and
if so: how many of the advanced/non advanced synchronous cancer were already detectable?
2. What is the conclusion by the authors concerning the decision made by the surgeon: Did
preoperative colonoscopy change the decision for colon resection? In how many cases were the
synchronous tumors next to the obstruction and in how many cases distant to the obstruction?
3. Which definition did you use for advanced / non advanced colon cancer
4. Is it possible including the preoperative UICC tumor stadium for all patients? It is not clear
if some patients were resected in a palliative manner or only curative intent.
5. Please provide patient data (gender, age, etc.)
6. 86/98 patients with total colonoscopy after SEMS placement. Why did 12 patients not undergo
colonoscopy?
7. Figure 1 box “TCS”: patients
8. Table 3: Is it possible to declare what kind of cancerous lesions were present (Paris
classification?)
9. Table 3: number of total synchronous cancer (lesion/patient): should be 13/12 and not 13/11?
10. It would also be helpful to declare the Boston Bowel Preparation score in patients which
had TCS after SEMS placement. This could help understand the rate of remaining lesions
encountered 1 year after colonic resection on follow up endoscopy.
11. Please declare if the data was retrospectively analyzed or prospectively collected.
Kind regards.
Please review this paper.
user
Title: Importance of preoperative total colonoscopy and endoscopic resection after self-
expandable metallic stent placement for obstructive colorectal cancer as a bridge-to-surgery
Version: 3 Date: 18 May 2023
Reviewer's report:
Dear Editors,
thank you very much for letting me review this interesting paper.
The authors show their experience in 100 patients treated with SEMS placement for obstructive
colon cancer and the findings observed at pre-operative total colonoscopy enabled by SEMS
placement.  Preoperative total colonoscopy was performed in 86/100 patients. In 47 patients
a total of 143 lesions were endoscopically resected, including 9 non advanced synchronous
cancers. Additionally 4 advanced synchronous colon cancer were found at preoperative
colonoscopy.
International guidelines do not specifically recommend total colonoscopy prior to colonic
resection for obstructive cancer after SEMS placement. Therefore, it is interesting to see
the findings the authors made and might have changed the operative management of the
patients. Additionally, the findings by the authors shed some light on feasibility of preoperative
colonoscopy and feasibility of trans- stent endoscopic resection methods (CSP/EMR/ESD).
I would accept it for publication, but have some questions/remarks:
1. Did all patients undergo complete CT scans of the oncologic disease prior to colonoscopy and
if so: how many of the advanced/non advanced synchronous cancer were already detectable?
2. What is the conclusion by the authors concerning the decision made by the surgeon: Did
preoperative colonoscopy change the decision for colon resection? In how many cases were the
synchronous tumors next to the obstruction and in how many cases distant to the obstruction?
3. Which definition did you use for advanced / non advanced colon cancer
4. Is it possible including the preoperative UICC tumor stadium for all patients? It is not clear
if some patients were resected in a palliative manner or only curative intent.
5. Please provide patient data (gender, age, etc.)
6. 86/98 patients with total colonoscopy after SEMS placement. Why did 12 patients not undergo
colonoscopy?
7. Figure 1 box “TCS”: patients
8. Table 3: Is it possible to declare what kind of cancerous lesions were present (Paris
classification?)
9. Table 3: number of total synchronous cancer (lesion/patient): should be 13/12 and not 13/11?
10. It would also be helpful to declare the Boston Bowel Preparation score in patients which
had TCS after SEMS placement. This could help understand the rate of remaining lesions
encountered 1 year after colonic resection on follow up endoscopy.
11. Please declare if the data was retrospectively analyzed or prospectively collected.
Kind regards.
assistant