NAFLD is tightly associated with various diseases such as diabetes, cardiovascular disease, kidney disease, and cancer. Previous studies had investigated the association between NAFLD and various extrahepatic cancers, but the available data to date is not conclusive. The aim of this study was to investigate the association between NAFLD and various extrahepatic cancers comprehensively. Searches were conducted of various electronic databases (PubMed, EMBASE, Medline, and the Cochrane Library) to identify observational studies published between 1996 and January 2020 which investigated the association between NAFLD and extrahepatic cancers. The pooled OR/HR/IRR of the association between NAFLD and various extrahepatic cancers were analyzed. A total of 26 studies were included to investigate the association between NAFLD and various extrahepatic cancers. As the results shown, the pooled OR values of the risk of colorectal cancer and adenomas in patients with NAFLD were 1.72 (95%CI: 1.40–2.11) and 1.37 (95%CI: 1.29–1.46), respectively. The pooled OR values of the risk of intrahepatic cholangiocarcinoma and extrahepatic cholangiocarcinoma in patients with NAFLD were 2.46 (95%CI: 1.77–3.44) and 2.24 (95%CI: 1.58–3.17), respectively. The pooled OR value of the risk of breast cancer in patients with NAFLD was 1.69 (95%CI: 1.44–1.99). In addition, NAFLD was also tightly associatied with the risk of gastric cancer, pancreatic cancer, prostate cancer, and esophageal cancer. NAFLD could significantly increase the development risk of colorectal adenomas and cancer, intrahepatic and extrahepatic cholangiocarcinoma, breast, gastric, pancreatic, prostate, and esophageal cancer. NAFLD could be considered as one of the influencing factors during the clinical diagnosis and treatment for the extrahepatic cancers.

中文翻译：

---

非酒精性脂肪肝与肝外癌症之间的关联：系统评价和荟萃分析。

NAFLD与多种疾病紧密相关，例如糖尿病，心血管疾病，肾脏疾病和癌症。先前的研究已经调查了NAFLD与各种肝外癌症之间的关联，但是迄今为止可获得的数据尚不确定。这项研究的目的是全面研究NAFLD与各种肝外癌之间的关系。搜索了各种电子数据库（PubMed，EMBASE，Medline和Cochrane图书馆），以鉴定1996年至2020年1月发表的观察性研究，这些研究调查了NAFLD与肝外癌症之间的关系。分析了NAFLD与各种肝外癌之间关联的合并OR / HR / IRR。总共包括26项研究，以调查NAFLD与各种肝外癌症之间的关系。结果显示，NAFLD患者合并大肠癌和腺瘤风险的OR值分别为1.72（95％CI：1.40–2.11）和1.37（95％CI：1.29–1.46）。NAFLD患者肝内胆管癌和肝外胆管癌风险的总OR值分别为2.46（95％CI：1.77–3.44）和2.24（95％CI：1.58–3.17）。NAFLD患者的乳腺癌风险汇总OR值为1.69（95％CI：1.44-1.99）。此外，NAFLD还与胃癌，胰腺癌，前列腺癌和食道癌的风险密切相关。NAFLD可能会大大增加大肠腺瘤和癌症的发展风险，肝内和肝外胆管癌，乳腺癌，胃癌，胰腺癌，前列腺癌和食道癌。NAFLD可被认为是肝外癌临床诊断和治疗过程中的影响因素之一。