Impact of maintenance therapy with fluoropyrimidines in advanced esophageal-gastric adenocarcinoma: a critical review

We are writing this letter to comment on the article “Impact of maintenance therapy with fluoropyrimidines in advanced esophageal-gastric adenocarcinoma” by Abdel Karim Dip Borunda et al. (1). The author should be appreciated for studying the maintenance therapy with fluoropyrimidines in advanced gastric cancer. Advanced gastric cancer has poor outcomes, and there is limited evidence about maintenance chemotherapy, especially in non-Asian populations. This study provides real-world data from a Mexican hospital and helps to fill this gap. The large number of patients and clear presentation of results add value to the study. This study highlights the potential role of maintenance therapy in recurrent and metastatic gastric cancer. However, despite these strengths, some limitations in the study needs to be discussed to interpret the better result.

In the article, only those patients were included who responded to the treatment that were complete response (CR), partial response (PR), stable disease (SD). Patients with poor prognosis or progressive disease were excluded, due to which selection bias occurred. Among the 278 patients who were treated with first line therapy, only 190 (68%) patients were analyzed and (32%) were excluded who had progressive disease. Exclusion of these patients interfere with the results because this study enriched the population with better prognosis, over estimating the progression-free survival (PFS) and overall survival (OS) (2,3).

Furthermore, in the study, all the patients did not receive the same first line of therapy. Instead, different treatment regiments were used before starting maintenance therapy. All these regiments have different drugs, different strength of the drugs, toxicities and effects on survivals. Because PFS and OS depend not only on the maintenance dose but also on how strong the initial therapy was and how well the patients responded to that, it becomes difficult to know whether the survival is due to the first-line regimen or the maintenance therapy (2,4).

Moreover, the study was conducted in a single centered, tertiary care hospital in Mexico City. Although the data provides valuable result in the specific population but the findings may not be applicable to the patients in different regions or hospitals. Difference in patient demographic, treatment protocols, resource availability and supportive care may influence the results. Single-centered studies are more prone to institutional biases, such as specific preferences in regimens, dose adjustments, or toxicity management strategies. These differences can affect the PFS and OS results (5,6).

Furthermore, although the study included patients aged between 29 and 86 years, it didn’t divide the patients according to age groups. Age can affect survival and how well patients tolerate chemotherapy. For example, old age patients may have more health problem that may shorten their PFS and OS. By combining all ages together, the reported results may hide important differences between younger and older patients. This makes it harder to apply the findings to individual patients, especially when deciding the treatment plans for older adults. Including age-stratified analysis would have made the study more reliable (7).

Acknowledgments

None.

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-2026-1-0010/coif). The authors have no conflicts of interest to declare.

Ethical Statement: The authors are accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved.

Open Access Statement: This is an Open Access article distributed in accordance with the Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International License (CC BY-NC-ND 4.0), which permits the non-commercial replication and distribution of the article with the strict proviso that no changes or edits are made and the original work is properly cited (including links to both the formal publication through the relevant DOI and the license). See: https://creativecommons.org/licenses/by-nc-nd/4.0/.

References

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