对于没有令人担忧的特征（WFs）或高危特征（HRS）的分支管导管内乳头状粘液性肿瘤（BD-IPMN），当前指南建议进行监测。然而，这些导管内乳头状粘液性肿瘤（IPMN），尤其是小而稳定的肿瘤，恶变的风险较低。我们的目的是评估小囊肿大小和缺乏快速生长是否可以防止 WFs/HRS 和恶性肿瘤（高度不典型增生 (HGD) 或胰腺癌 (PC)）的发展。PubMed/Medline、Embase、Cochrane 图书馆从成立到 2023 年 5 月，对 Web of Science 核心合集进行了系统检索，以确定调查低风险 BD-IPMN 监测结果的研究。评估基线囊肿大小和/或生长与 WFs/HRS 和/或 HGD/PC 相关的研究也包括在内。纽卡斯尔-渥太华量表工具用于评估研究质量。在 1937 年确定的手稿中，有 21 项研究符合纳入条件。这些研究的质量被认为是合理的。 13 项相关研究中有 11 项发现囊肿大小与 WFs/HRS 发展之间呈负相关，但只有九分之一的研究报告了囊肿大小与恶性肿瘤之间的负相关。关于囊肿生长，六分之四的研究描述了与 WFs/HRS 发展的负相关性，并且所有六项研究都报告了与恶性肿瘤的负相关性。囊肿≤15毫米发生WF/HRS或恶性肿瘤的汇总相对风险(RR)为0.37 (95% CI 0.25-0.57)，囊肿生长<2-2.5毫米/年发生恶性肿瘤的RR为0.04 (95% CI 0.25-0.57) CI 0.02-0.09))。这项系统评价和荟萃分析表明，小而稳定的低风险 BD-IPMN 与明显较低的进展率相关，稳定的囊肿大小是最令人放心的特征。由于定义和报告的结果测量存在很大的异质性，需要前瞻性研究来确认可以减弱甚至停止对小型且稳定大小的囊肿的监测。© 2024 作者。 《联合欧洲胃肠病学杂志》由 Wiley periodicals LLC 代表联合欧洲胃肠病学出版。

For branch-duct intraductal papillary mucinous neoplasms (BD-IPMNs) without worrisome features (WFs) or high-risk stigmata (HRS), current guidelines recommend surveillance. However, these intraductal papillary mucinous neoplasm (IPMNs), especially the small and stable-sized ones, carry a low risk of malignant transformation. Our aim was to assess whether small cyst size and absence of rapid growth provide reassurance against the development of WFs/HRS and malignancy (high-grade dysplasia (HGD) or pancreatic cancer (PC)).PubMed/Medline, Embase, the Cochrane Library and the Web of Science Core Collection were systematically searched from inception to May 2023 to identify studies investigating surveillance outcomes of low-risk BD-IPMNs. Studies assessing baseline cyst size and/or growth in relation to WFs/HRS and/or HGD/PC were included. The Newcastle-Ottawa scale tool was used to assess study quality.Of the 1937 identified manuscripts, 21 studies were eligible for inclusion. The quality of these studies was considered reasonable. A negative association between cyst size and WFs/HRS development was found in 11 out of 13 relevant studies, but only one out of nine studies reported a negative association between size and malignancy. Regarding cyst growth, four out of six studies described a negative association with the development of WFs/HRS, and all six reported a negative association with malignancy. The pooled relative risk (RR) of developing WFs/HRS or malignancy for cysts ≤15 mm was 0.37 (95% CI 0.25-0.57) and the RR of developing malignancy for cyst growth <2-2.5 mm/year was 0.04 (95% CI 0.02-0.09)).This systematic review and meta-analysis shows that small and stable-sized low-risk BD-IPMNs are associated with a markedly low progression rate, with stable cyst size being the most reassuring feature. Because of substantial heterogeneity in definitions and reported outcome measures, prospective studies are needed to confirm that surveillance of small and stable sized cyst can be de-intensified or even discontinued.© 2024 The Author(s). United European Gastroenterology Journal published by Wiley Periodicals LLC on behalf of United European Gastroenterology.