胰腺导管腺癌（pancreatic ductal adenocarcinoma，PDAC）作为最常见的一类胰腺恶性肿瘤，其神经侵袭的发生率高达80%~98%，远超任何其他实体瘤。而其神经侵袭被定义为在包绕神经/神经鞘的神经外膜、神经周围以及神经内膜部位发现PDAC细胞。众多研究已证明，PDAC神经侵袭的发生与更快的疾病进展、更高的肿瘤局部复发率以及更加不良的患者预后均密切相关。PDAC的神经侵袭与胰腺肿瘤微环境中多种类型的特异性/非特异性免疫细胞以及神经胶质相关细胞的行为/相互作用存在相关性，这些行为贯穿于PDAC进展的始终。研究显示，施万细胞、胰腺星状细胞、肿瘤相关巨噬细胞甚至T细胞等众多肿瘤微环境的细胞组成成分，均与PDAC神经侵袭的发生有关。这些关联均是基于上述细胞的细胞间作用及一系列细胞内信号通路。该综述总结并介绍了近年来PDAC神经侵袭细胞学机制领域的研究进展。对其机制进行详尽的研究或有助于新靶点及治疗方式的发现，为未来控制甚至逆转PDAC的神经侵袭过程提供理论依据，并将改善PDAC患者的预后变为可能。

Pancreatic ductal adenocarcinoma (PDAC) is the most common type of pancreatic malignant tumor, and the incidence of neural invasion of PDAC is as high as 80%?98%, far higher than any other solid tumor. Its neural invasion is defined as the discovery of PDAC cells in the nerve adventitia, perinerve and neurointima surrounding the nerve/nerve sheath. Many studies have shown that the occurrence of neural invasion in PDAC is closely related to faster disease progression, higher local recurrence rate and worse prognosis. The neural invasion of PDAC is related to the behavior/interaction of various types of specific/non-specific immune cells and glial-related cells in the pancreatic tumor microenvironment. These behaviors run through the progression of PDAC. Studies show that Schwann cells, pancreatic stellate cells, tumor-associated macrophages and even T cells, are related to the occurrence of neural invasion of PDAC, which is based on the cell-cell interaction of the above cells and a series of intracellular signal pathways. This review summarizes and introduces the research progress in the field of cytological mechanism of PDAC neural invasion in recent years. Detailed studies of its mechanism may contribute to the discovery of new targets and treatment methods, provide a theoretical basis for controlling or even reversing the neural invasion process of PDAC in the future, and make it possible to improve the prognosis of patients with PDAC.