Letter to the Editor on: “The Effects of Physical Exercise on Tumor Vasculature: Systematic Review and Meta-Analysis.”

Dear Editor,

We read with interest the recent article “The Effects of Physical Exercise on Tumor Vasculature: Systematic Review and Meta-analysis” [1] and after careful appraisal and consideration we feel that some aspects of the data and analysis warrant further review. The study reported some promising results, namely that both chronic and acute exercise appear to improve intratumoral vascularisation in animal models. This is an important finding given increased vascularisation through tumor modulation may have the potential to improve chemotherapy delivery and efficacy [2]. However, after conducting further investigations, we query several details in the data extraction and analysis decision-making that we believe impact the conclusions of this article.

Publication History

Article published online:
01 March 2022

• References

• 1 Esteves M, Monteiro MP, Duarte JA. The effects of physical exercise on tumor vasculature: systematic review and meta-analysis. Int J Sports Med 2021; 42: 1237-1249
• 2 Florez Bedoya CA, Ferreira Cardoso AC, Parker N. et al. Exercise during preoperative therapy increases tumor vascularity in pancreatic tumor patients. Sci Rep 2019; 9: 13966
• 3 Higgins JPT, Thomas J, Chandler J. et al. (editors) Cochrane Handbook for Systematic Reviews of Interventions version 6.2 (updated February 2021). Cochrane 2021. Available from. www.training.cochrane.org/handbook
• 4 Borenstein M. ed. Introduction to Meta-Analysis. Chichester, U.K: John Wiley & Sons; 2009
• 5 Hooijmans CR, IntHout J, Ritskes-Hoitinga M. et al. Meta-analyses of animal studies: an introduction of a valuable instrument to further improve healthcare. ILAR J 2014; 55: 418-426
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• 8 Morrell MBG, Alvarez-Florez C, Zhang A. et al. Vascular modulation through exercise improves chemotherapy efficacy in ewing sarcoma. Pediatr Blood Cancer 2019; 66