Review for 10.1186/s12876-024-03441-2 (2024)

Title: Clinical outcomes of drug-coated balloons dilatation for benign esophageal stricture
Version: 2 Date: 04 Sep 2024
Reviewer's report:
This is a review of the manuscript entitled “Clinical outcomes of drug-coated balloons dilatation
for refractory benign esophageal stricture” This is an innovative small case series aiming to
improve the efficacy of dilation in refractory benign esophageal strictures (RBES) by utilizing
drug-coated balloon dilatation (DCB). The concept is primarily derived from the use of DCBs
with antiproliferative agents, which aim to prevent restenosis in various arterial diseases during
endovascular treatments. The authors report a clinical success rate of approximately 84% at a
median follow-up duration of 12 months, with no serious complications noted. This study has
the potential to advance the field of endoscopic treatment for benign esophageal stricture (BES).
However, there are several unclear and concerning points that need to be addressed.
1) The definition of refractory benign esophageal stricture must be clearly defined in the
inclusion criteria. The statement, “failed in repeated push-type dilators or balloon dilation in the
methods section, and 2 patients underwent bougienage, but showed poor efficacy in the results
section,” does not accurately represent RBES. The most widely accepted definition of RBES
was originally proposed by Dr. Kochman. If the characteristics of the patients in this study do
not align with RBES, they should be classified as benign esophageal stricture (BES). The term
“refractory” should be removed from the manuscript, particularly from the title and the study's
objective. The differences between BES and RBES are significant in terms of prognosis and
treatment outcomes.
2) Details regarding the drug used in the coated balloon should be provided. The potential
mechanisms by which the drug may affect the restenosis of esophageal strictures should be
discussed. Additionally, general potential side effects of the drug should be mentioned in
the discussion section, along with specific side effects that may arise, if any in the event
of esophageal perforation following dilation, particularly if the drug could contaminate the
mediastinum.
3) Technical and clinical success should be clearly defined. The authors state in the methods
section that “Technical success rate was defined as a less than 20% decrease in stricture index
after dilatation,” In my understanding, a "less than 20% decrease in stricture index" implies
minimal improvement, which seems counterintuitive to the definition of "technical success." For
a dilatation procedure, success is typically associated with a significant improvement, indicating
a larger decrease in the stricture index. Therefore, it should be defined as “more than 20%.”
In addition, the authors report that the clinical success rate of DCBs dilatation is 84.2% in
the results section; however, they do not mention the technical success rate. Furthermore, the
definition of clinical success has not been included in the definitions section. The authors should
either add a definition of clinical success in the definitions section or revise the term from clinical
to technical success in the results section.
4) Potential indications for utilizing DCBs in BES should be addressed in the discussion section.
Based on the authors' experience, it is crucial to clarify whether DCBs should be employed as a
first-line treatment or only after standard dilation has failed or under other specific conditions.
5) Some grammatical errors need to be corrected.