人体是数万亿共生微生物的栖息地，统称为人类微生物群，其中大约一半存在于肠道中。近年来，新一代测序技术的发展促进了人类微生物群的分析。越来越多的证据似乎支持微生物群与宿主之间互惠关系的破坏（即生态失调）与包括乳腺恶性肿瘤在内的多种疾病的发展之间存在严格关系。乳腺癌仍然是女性癌症相关死亡的最常见原因。它与肠道微生物群的复杂关系是越来越多证据的对象。事实上，与宿主免疫系统的相互作用以及肠道微生物群对雌激素、脂质和多酚代谢的直接影响似乎可能影响乳腺肿瘤的发生、进展和对治疗的反应。在这篇综述中，为了帮助肿瘤学家驾驭这个快速发展的研究领域，我们对最常用的分类法、主要分析技术和术语进行了基本概述。我们讨论了目前已知的肠道微生物群与乳腺癌之间相互作用的情况，以及利用这种复杂的相互作用进行治疗的潜在努力，并修订了正在进行的主要研究。我们还简要概述了乳腺癌瘤内微生物群及其在肠道微生物群之外的潜在作用。版权所有 © 2024 作者。由爱思唯尔有限公司出版。保留所有权利。

The human body represents the habitat of trillions of symbiotic microorganisms, collectively known as human microbiota, approximately half of which residing in the gut. The development of next-generation sequencing techniques has boosted the profiling of human microbiota in recent years. A growing body of evidence seems to support a strict relationship between the disruption of the mutualistic relationship between the microbiota and the host (i.e., dysbiosis) and the development of several diseases, including breast malignancies. Breast cancer still represents the most frequent cause of cancer-related death in women. Its complex relationship with gut microbiota is the object of a growing body of evidence. In fact, the interaction with the host immune system and a direct impact of gut microbiota on estrogen, lipid and polyphenols metabolism, seem to potentially affect breast tumor development, progression and response to treatments. In this review, in an attempt to help oncologists navigating this rapidly-evolving research field, we provide an essential overview on the taxonomy, main analytical techniques and terminology most commonly adopted. We discuss what is currently known regarding the interaction between gut microbiota and breast cancer and potential efforts to harness this complex interplay for therapeutic purposes, and revise main ongoing studies. We also briefly provide an overview on breast cancer intratumoral microbiota and its potential role beyond gut microbiota.Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.