Critical analysis of prognostic study in esophageal squamous cell carcinoma
The retrospective study by Li et al. (1) aimed to explore local radical therapy (LRT) for oligometastatic esophageal squamous cell carcinoma (ESCC), and it offers valuable insights. However, several methodological and analytical limitations should be considered in this study.
Firstly, the non-randomized design introduces significant selection bias. While the authors adjusted for basic confounders, such as age, critical variables such as metastatic sites, patients’ willingness and other factors may influence the decision of the therapeutic schedule. Advanced causal inference methods such as propensity score matching (2) are necessary to minimize the bias.
Secondly, the “low-risk” definition in this paper relies solely on anatomic criteria, ignoring growth rate, biological markers, and other factors (3). This oversimplification may cause misclassification, as tumor biology level can impact the outcomes.
Thirdly, the modest sample size (n=83) raises concerns about the statistical power. Adding stratified subgroup analysis for different local treatment methods such as surgery versus radiation therapy and systemic treatment plans will be helpful to clarify the specific efficacy of different treatment methods.
Finally, survival curves beyond 24 months show wide confidence intervals, reflecting the limited value of long-term data. The median follow-up duration should be reported explicitly.
These limitations highlight the need for prospective validation using standardized oligometastasis criteria and strict adjustment for confounding factors. Nonetheless, this study provides important evidence supporting LRT in selected ESCC patients.
Acknowledgments
We would like to thank James Lu, Language Institution of Yulin University for his help in polishing our paper.
Footnote
Provenance and Peer Review: This article was a standard submission to the journal. The article did not undergo external peer review.
Funding: None.
Conflicts of Interest: Both authors have completed the ICMJE uniform disclosure form (available at https://jgo.amegroups.com/article/view/10.21037/jgo-2025-173/coif). The authors have no conflicts of interest to declare.
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References
- Li T, Ke D, Fu X, et al. Prognosis for local radical treatment in patients with esophageal squamous cell carcinoma with low-risk oligometastatic recurrence after curative resection: a retrospective cohort study. J Gastrointest Oncol 2024;15:807-17. [Crossref] [PubMed]
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- Guckenberger M, Baus WW, Blanck O, et al. Definition and quality requirements for stereotactic radiotherapy: consensus statement from the DEGRO/DGMP Working Group Stereotactic Radiotherapy and Radiosurgery. Strahlenther Onkol 2020;196:417-20. [Crossref] [PubMed]
