In clinical studies, it has been observed that esophageal cancer (EC) patient prognosis can be very different even for those patients with tumors of the same TNM stage. Tumor length has been analysed as a possible independent prognostic factor in many studies, but no unanimous conclusion has been reached. Therefore, this review used a meta-analysis to evaluate the association between tumor length and prognosis in EC patients. A systematic search for relevant articles was performed in PubMed, Web of Science, and Embase. Hazard ratios (HRs) and 95% confidence intervals (CIs) were used as effective measures to estimate the correlation between tumor length and prognosis, including overall survival, disease-free survival, progression-free survival, disease-specific survival, and cancer-specific survival. STATA 15.0 software was used to perform the meta-analysis and the data synthesis. Finally, 41 articles with 28,973 patients were included in our study. The comprehensive statistical results showed that long tumors are an independent prognostic parameter associated with poor overall survival (OS) (HR = 1.30; 95% CI: 1.21–1.40, p < .001) and disease-free survival (DFS) (HR = 1.38; 95% CI: 1.18–1.61, p < .001) in EC patients. Subgroup analyses also suggested a significant correlation between long tumors and poor OS. Sensitivity analysis and publication bias evaluation confirmed the reliability and stability of the results. Similar results were obtained in the analyses of progression-free survival (PFS), disease-specific survival (DSS), and cancer-specific survival (CSS). The results of this meta-analysis showed that long tumors were related to poor OS, DFS, PFS, DSS and CSS in EC patients. Tumor length might be an important predictor of prognosis in EC patients, and it can be used as an independent staging index. Further well-designed and large-scale prospective clinical studies are needed to confirm these findings.

中文翻译：

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肿瘤长度对食管癌预后的影响：系统评价和荟萃分析

临床研究发现，即使肿瘤的TNM分期相同，食管癌（EC）患者的预后也可能有很大差异。许多研究已将肿瘤长度作为可能的独立预后因素进行分析，但尚未达成一致的结论。因此，本综述采用荟萃分析来评估 EC 患者肿瘤长度与预后之间的关联。在 PubMed、Web of Science 和 Embase 中对相关文章进行了系统检索。风险比（HR）和95％置信区间（CI）被用作估计肿瘤长度和预后之间相关性的有效措施，包括总生存期、无病生存期、无进展生存期、疾病特异性生存期和癌症-具体的生存。使用STATA 15.0软件进行荟萃分析和数据合成。最后，我们的研究纳入了涉及 28,973 名患者的 41 篇文章。综合统计结果显示，长肿瘤是一个独立的预后参数，与较差的总生存期 (OS) (HR = 1.30; 95% CI: 1.21–1.40, p < .001) 和无病生存期 (DFS) (HR = 1.30) 相关。 EC 患者中为 1.38；95% CI：1.18–1.61，p < .001）。亚组分析还表明，长肿瘤与较差的 OS 之间存在显着相关性。敏感性分析和发表偏倚评估证实了结果的可靠性和稳定性。在无进展生存期（PFS）、疾病特异性生存期（DSS）和癌症特异性生存期（CSS）的分析中也获得了类似的结果。这项荟萃分析的结果表明，长肿瘤与 EC 患者的 OS、DFS、PFS、DSS 和 CSS 较差有关。肿瘤长度可能是 EC 患者预后的重要预测因素，可作为独立的分期指标。需要进一步精心设计和大规模的前瞻性临床研究来证实这些发现。