为了评估磁共振成像（MRI）与扩散加权成像（DWI）相对于增强计算机断层扫描（CECT）单独在胰腺癌术前评估中是否具有附加价值，进行了系统综述和荟萃分析。通过2022年10月在MEDLINE、EMBASE和Cochrane数据库中搜索相关的已发表研究。符合条件的研究必须评估MRI与DWI在新诊断胰腺癌术前评估中的病人级诊断性能，与CECT进行对比。我们的主要结局是为了防止一次徒劳手术所需治疗的人数（NNT），使用MRI与DWI，定义为CECT为阴性而MRI与DWI为阳性的肝转移（即CECT漏掉的转移性疾病的手术干预）。次要结局是确定MRI与DWI的诊断性能和NNT，以改变胰腺癌的治疗方案。符合纳入标准的研究共有9个，共1121名患者，其中172例（15.3%）有肝转移。MRI与DWI减少的徒劳手术比例为6.0%（95% CI，3.0-11.6%），对应的NNT为16.6。MRI与DWI改变管理的病例比例为18.1%（95% CI，9.9-30.7），对应的NNT为5.5。MRI的病人级敏感性和特异性分别为92.4%（95% CI，87.4-95.6%）和97.3%（95% CI，96.0-98.1%）。MRI与DWI可能通过改善术前CECT对隐匿性肝转移的检测来防止胰腺癌的徒劳手术，其NNT为16.6。MRI与DWI在胰腺癌肝转移的标准术前CECT评估中起到了补充作用，改善了手术候选人的选择，防止了不必要的手术。•对于在CECT中肝转移隐匿的患者（即CECT为阴性，MRI与DWI为阳性），MRI与DWI防止潜在的徒劳手术的NNT为16.6。•MRI与DWI更高的肝转移检测性能可以归因于对亚厘米级肝转移的更高检测率。© 2023.作者（们）通过独家许可，授权给欧洲放射学会。

To perform a systematic review and meta-analysis to evaluate if magnetic resonance imaging (MRI) with diffusion weighted imaging (DWI) adds value compared to contrast-enhanced computed tomography (CECT) alone in the preoperative evaluation of pancreatic cancer.MEDLINE, EMBASE, and Cochrane databases were searched for relevant published studies through October 2022. Studies met eligibility criteria if they evaluated the per-patient diagnostic performance of MRI with DWI in the preoperative evaluation of newly diagnosed pancreatic cancer compared to CECT. Our primary outcome was the number needed to treat (NNT) to prevent one futile surgery using MRI with DWI, defined as those in which CECT was negative and MRI with DWI was positive for liver metastasis (i.e., surgical intervention in metastatic disease missed by CECT). The secondary outcomes were to determine the diagnostic performance and the NNT of MRI with DWI to change management in pancreatic cancer.Nine studies met the inclusion criteria with a total of 1121 patients, of whom 172 had liver metastasis (15.3%). The proportion of futile surgeries reduced by MRI with DWI was 6.0% (95% CI, 3.0-11.6%), yielding an NNT of 16.6. The proportion of cases that MRI with DWI changed management was 18.1% (95% CI, 9.9-30.7), corresponding to an NNT of 5.5. The per-patient sensitivity and specificity of MRI were 92.4% (95% CI, 87.4-95.6%) and 97.3% (95% CI, 96.0-98.1).MRI with DWI may prevent futile surgeries in pancreatic cancer by improving the detection of occult liver metastasis on preoperative CECT with an NNT of 16.6.MRI with DWI complements the standard preoperative CECT evaluation for liver metastasis in pancreatic cancer, improving the selection of surgical candidates and preventing unnecessary surgeries.• The NNT of MRI with DWI to prevent potential futile surgeries due to occult liver metastasis on CECT, defined as those in which CECT was negative and MRI with DWI was positive for liver metastasis, in patients with pancreatic cancer was 16.6. • The higher performance of MRI with DWI to detect liver metastasis occult on CECT can be attributed to an increased detection of subcentimeter liver metastasis.© 2023. The Author(s), under exclusive licence to European Society of Radiology.