Review for 10.1186/s12876-025-04015-6 (2025)

Title: Trends in Incidence and Mortality of Early-Onset Gastrointestinal Cancers: A
Comprehensive Study
Version: 0 Date: 04 Mar 2025
Reviewer:  Aref Yarahmadi
Reviewer's report:
General Comments
The manuscript provides a comprehensive analysis of the global burden and trends of early-onset
gastrointestinal cancers from 1990 to 2019, utilizing data from the Global Burden of Disease
2019 study. The study is well-structured, with a clear focus on the epidemiology of early-onset
gastrointestinal cancers, including incidence, mortality, and risk factors. The authors have done
a commendable job in presenting a detailed analysis of the data, stratified by age, sex, region,
and sociodemographic index. However, there are several areas where the manuscript could be
improved to enhance its clarity, methodological rigor, and overall impact.
Once these revisions are made, the manuscript will be suitable for publication.
Minor revisions
Formatting Instructions
Font: Times New Roman, size 12 for the main text.
Titles: Bold, Times New Roman, size 12.
Line Spacing: 1.5 for the entire document.
Please adjust the document according to these formatting guidelines.
Specific Comments
• The abstract provides a concise summary of the study's objectives, methods, results, and
conclusions. However, it could benefit from a brief mention of the key risk factors identified,
as this is a significant part of the study.
Introduction
• The introduction effectively sets the stage for the study by highlighting the increasing burden of
EO-GI cancers and the lack of comprehensive global studies on this topic. However, the authors
could strengthen this section by providing more context on why EO-GI cancers are particularly
concerning, such as their impact on younger populations and the potential differences in clinical
outcomes compared to later-onset cancers.
• The introduction could also benefit from a more detailed discussion of the potential risk factors
for EO-GI cancers, as this is a key focus of the study.
• Data Collection: The authors mention that data were collected from 204 countries and
territories, but it would be useful to provide more information on how data quality and
completeness were ensured, especially in low- and middle-income countries where cancer
registries may be less robust.
• Statistical Analysis: The authors describe the use of age-standardized rates and estimated
annual percentage change but could provide more detail on how these metrics were calculated,
particularly for readers who may not be familiar with these methods.
• Risk Factor Analysis: The authors mention the use of population attributable fractions (PAFs)
and summary exposure values (SEVs) but do not provide sufficient detail on how these were
calculated or how risk factors were selected for inclusion in the analysis.
Results
• Global Trends: The authors report that the absolute number of EO-GI cancer cases and deaths
has increased, while the age-standardized rates have decreased. This is an important finding,
but the authors should discuss potential reasons for this discrepancy, such as population growth,
aging, or improvements in cancer detection and treatment.
Figure
• Ensure axis titles and legends are legible (e.g., Figure S3’s small font size for country/region
names).
Table
• Tables S1-S2 and S3-S8 suffer from inconsistent column alignment and excessive line breaks,
hindering readability. Use consistent decimal places and improve spacing.
• The tables are unclear and too busy. Use a smaller font size and tidy up the formatting.
• Clarify abbreviations in table footnotes for readers unfamiliar with GBD terminology.
• Verify consistency between tables and figures.
Discussion
• The discussion section is thorough and well-reasoned, but it could be strengthened by
addressing some of the limitations of the study more explicitly. For example:
• Data Limitations: The authors acknowledge that cancer registries in some regions may
introduce bias, but they do not discuss how this might affect the interpretation of their findings.
For example, underreporting in low-income countries could lead to an underestimation of the
true burden of EO-GI cancers in these regions.
• Risk Factor Analysis: The authors discuss the role of smoking and high BMI in EO-GI cancers
but do not explore other potential risk factors, such as alcohol consumption, diet, or physical
inactivity, which have been implicated in other studies.
• Implications for Prevention: The authors briefly mention the importance of primary prevention
but do not provide specific recommendations for how to reduce the burden of EO-GI cancers.
conclusion
• The conclusion is concise and summarizes the key findings of the study. However, it could be
strengthened by providing more specific recommendations for future research and public health
interventions, particularly in high-burden regions.
Please ensure to utilize and reference the following two articles, as they provide valuable
insights and data that can significantly enhance the quality and depth of your manuscript. These
references will strengthen your arguments and contribute to the overall improvement of your
paper:
Article 1: https://doi.org/10.3389/fonc.2023.1344328
Article 2: https://doi.org/10.1136/gutjnl-2024-333227