Abstract: Breast cancer is the highest prevalent malignant tumor worldwide，with a variety of histological types，among which invasive lobular carcinoma（ILC）of breast is the second most common histologic type，accounting for about 5%-15% of invasive tumors，showing an increased prevalence in the past 30 years. The major characteristic of ILC of breast is the loss of E-cadherin，which leads to the absence of adhesion between cells. The special diffuse infiltration and growth of ILC of breast pose some challenges to clinical physical and imaging examinations. Even if most patients with ILC of breast are hormone-receptor positive and sensitive to endocrine therapy，the problem of treatment resistance is inevitable in clinical applications. In addition，recent studies have found that the prognosis of ILC of breast is not as good as previously reported，and the principle of treatment based only on tumor stage and molecular typing does not seem to be fully applicable. It is possibly necessary to study ILC of breast as an independent clinical entity. In this paper，we reviewed the epidemiological and clinical characteristics，pathological and molecular characteristics，diagnosis，treatment，prognosis，and future treatment of ILC of breast，so as to better clinicians' understanding of clinical diagnosis and individualized treatment of ILC of breast.

Key words: Breast neoplasms；Carcinoma, lobular；Neoplasm invasiveness；Diagnosis；Therapy；Prognosis；Review

摘要： 乳腺癌是目前全球范围内发病率最高的恶性肿瘤，且组织学类型多样。乳腺浸润性小叶癌（ILC）是第二大常见浸润性乳腺癌组织学亚型（占5%~15%），近三十年来其发病率有所升高。E-钙黏蛋白表达缺失是乳腺ILC最主要的分子特征，可导致细胞间缺乏黏附性、肿瘤呈特殊弥漫性浸润生长，这给临床查体及影像学检查带来了一定挑战。尽管多数乳腺ILC患者激素受体呈阳性表达、对内分泌治疗反应良好，但也存在内分泌治疗耐药问题。此外，近年研究证实乳腺ILC患者预后并非如既往研究报道的那样良好，仅基于肿瘤分期及分子分型的治疗原则似乎并不完全适用于乳腺ILC，可能有必要将其作为独立的临床实体行进一步研究。本文主要综述了乳腺ILC的流行病学及临床特征、病理学及分子特征、诊断、治疗、预后、未来治疗方向等，以供临床医师更好地了解并优化乳腺ILC的临床诊断和个体化治疗参考。

关键词: 乳腺肿瘤；癌, 小叶状；肿瘤浸润；诊断；治疗；预后；综述