目前尚无关于甲状腺功能减退或甲状腺功能亢进与结直肠癌 (CRC) 风险之间关系的结论性信息。因此，我们的目的是总结关于甲状腺功能减退或甲状腺功能亢进与 CRC 风险之间关系的观察性研究的结果。使用在线数据库中的相关关键词进行文献检索，以查找截至 2023 年 7 月的适当出版物。使用随机效应模型来计算组合效应大小(ESs) 和 95% 置信区间 (CIs) 来调查甲状腺功能减退或甲状腺功能亢进与 CRC 风险之间的关系。在当前的系统评价和荟萃分析中，我们总共纳入了 13 项研究，总样本量为 33,557,450 例个体和 25,363 例CRC。汇总 13 个效应量显示甲状腺功能减退症与 CRC 风险之间没有显着关联（组合效应量：1.13，95% CI 0.87-1.48，P = 0.343）。甲状腺功能亢进症与 CRC 风险之间也没有显着相关性（综合效应大小：1.09，95% CI 0.75-1.57，P = 0.638）。此外，在远东研究中，甲状腺功能减退与结直肠癌风险之间存在显着关联，在中东，以及小样本量研究中，甲状腺功能亢进与结直肠癌风险之间存在显着关联。这项荟萃分析并未揭示甲状腺功能减退或甲状腺功能亢进与结直肠癌之间存在任何关联。 CRC.PROSPERO CRD42022331089.© 2023 的风险。作者获得 Springer Science Business Media, LLC（Springer Nature 旗下公司）的独家许可。

No conclusive information is available about the association between hypothyroidism or hyperthyroidism and risk of colorectal cancer (CRC). We therefore aimed to summarize the findings of observational studies on the relation between hypothyroidism or hyperthyroidism and risk of CRC.A literature search was conducted using relevant keywords in online databases for appropriate publications through July 2023. Random effects model was used to calculate combined effect sizes (ESs) and 95% confidence intervals (CIs) to investigate relationship between hypothyroidism or hyperthyroidism and CRC risk.Totally, we included 13 studies in the current systematic review and meta-analysis, with a total sample size of 33,557,450 individuals and 25,363 cases of CRC. Pooling 13 effect sizes revealed no significant association between hypothyroidism and risk of CRC (combined effect size: 1.13, 95% CI 0.87-1.48, P = 0.343). There was also no significant association between hyperthyroidism and risk of CRC (combined effect size: 1.09, 95% CI 0.75-1.57, P = 0.638). Additionally, there were significant associations between hypothyroidism and risk of CRC in the Far Eastern studies, between hyperthyroidism and risk of CRC in the Middle East, along with small sample size studies.This meta-analysis did not reveal any association between hypothyroidism or hyperthyroidism and risk of CRC.PROSPERO CRD42022331089.© 2023. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.