Revolutionizing lymph node metastasis imaging: the role of drug delivery systems and future perspectives

Abstract

The deployment of imaging examinations has evolved into a robust approach for the diagnosis of lymph node metastasis (LNM). The advancement of technology, coupled with the introduction of innovative imaging drugs, has led to the incorporation of an increasingly diverse array of imaging techniques into clinical practice. Nonetheless, conventional methods of administering imaging agents persist in presenting certain drawbacks and side effects. The employment of controlled drug delivery systems (DDSs) as a conduit for transporting imaging agents offers a promising solution to ameliorate these limitations intrinsic to metastatic lymph node (LN) imaging, thereby augmenting diagnostic precision. Within the scope of this review, we elucidate the historical context of LN imaging and encapsulate the frequently employed DDSs in conjunction with a variety of imaging techniques, specifically for metastatic LN imaging. Moreover, we engage in a discourse on the conceptualization and practical application of fusing diagnosis and treatment by employing DDSs. Finally, we venture into prospective applications of DDSs in the realm of LNM imaging and share our perspective on the potential trajectory of DDS development.

Keywords: Computed tomography; Drug delivery systems; Imaging; Lymph node metastasis; Magnetic resonance.

Fig. 1

The chronological progression—past, present, and anticipated future—of lymph node (LN) imaging via the medium of drug delivery systems (DDSs). Created with BioRender.com

Fig. 2

A brief historical overview of lymph node metastasis imaging based on DDSs. DDS drug delivery system, CT computed tomography, LSG lymphoscintigraphy, NP nanoparticle, MRI magnetic resonance imaging, ICG indocyanine green, SLN sentinel lymph node

Fig. 3

The targeted lymph node mechanisms of drug delivery systems (DDSs). A By modifying their surface charge, composition, and shape, DDSs possess the capability to elude phagocytosis activity by macrophages. B Benefitting from the EPR effect, DDSs can maintain a persistent presence within metastatic lymph nodes. C Leveraging the use of ligand-coupled NPs, DDSs have the potential to actively home in on targeted lymph nodes. D DDSs, when tailored to a specific size, gain the ability to infiltrate lymphatic vessels in substantial volumes. Created with BioRender.com

Fig. 4

The dual role of drug delivery systems (DDSs) in diagnosis and treatment, demonstrating the application of DDSs in delivering photothermal agents. These agents convert light energy into photoacoustic signals for imaging, while simultaneously releasing thermal energy, derived from light absorption, to annihilate tumor cells. Created with BioRender.com

Fig. 5

The potential risks associated with drug delivery systems (DDSs) in the context of lymph node metastasis imaging. Nanoparticle (NP)-based DDSs are not devoid of safety concerns. For instance, DDSs containing Gd may precipitate gadolinium deposition disease, causing symptoms such as fatigue and brain fog. Quantum dot-based DDSs may induce the production of reactive oxygen species (ROS) via the release of metal ions, such as the Cd ion, resulting in epigenetic modifications. Despite its initial status as an ideal, safe coating to mitigate DDS side effects, polyethylene glycol (PEG) might still instigate hypersensitivity reactions. Created with BioRender.com