- Review
Magnetic Particle Imaging in Oncology: Advances and Prospects for Tumor Progression Monitoring and Targeted Therapy
- Panangattukara Prabhakaran Praveen Kumar
Magnetic Particle Imaging (MPI) is a cutting-edge noninvasive imaging technique that offers high sensitivity, quantitative accuracy, and operates without the need for ionizing radiation compared to other imaging techniques. Utilizing superparamagnetic iron oxide nanoparticles (SPIONs) as tracers, MPI enables direct and precise visualization of target sites with no limitation on imaging depth. Unlike magnetic resonance imaging (MRI), which relies on uniform magnetic fields to produce anatomical images, MPI enables direct, background-free visualization and quantification of SPIONS within living organisms. This article provides an in-depth overview of MPI’s applications in tracking tumor development and supporting cancer therapy. The distinct physical principles that underpin MPI, including its ability to produce high-contrast images devoid of background tissue interference, facilitating accurate tumor identification and real-time monitoring of treatment outcomes, are outlined. The review outlines MPI’s advantages over conventional imaging techniques in terms of sensitivity and resolution, and examines its capabilities in visualizing tumor vasculature, tracking cellular movement, evaluating inflammation, and conducting magnetic hyperthermia treatments. Recent progress in tracer optimization and magnetic navigation has expanded MPI’s potential for targeted drug delivery, along with deep machine learning procedures for MPI applications. Additionally, considerations around safety and the feasibility of clinical implementation are also discussed in the present review. Overall, MPI is positioned as a promising tool in advancing cancer diagnostics, personalized therapy assessment, and noninvasive treatment strategies.
5 November 2025


![Principles and signal generation in magnetic particle imaging (MPI). (A) Schematic of the Berkeley MPI scanner setup. Image acquisition resembles projection scintigraphy, where magnetic nanoparticles traversing the field-free line (FFL) respond to an applied drive field (20 kHz, 20 mT). (B) Conceptual overview of a standard MPI scanner. Two large opposing rings generate a static selection field via d.c. currents, creating a central field-free point (FFP). The same rings also act as drive coils by superimposing a.c. currents on the d.c. field, while surrounding harmonic detection coils capture the particle response. (C) Design of an MPI system that encodes signals solely through drive fields. It incorporates dual selection field generators and three orthogonal pairs of drive coils to shift the FFP throughout the imaging volume. (D,E) Magnetization response of superparamagnetic particles. (D) Under an alternating magnetic field (H, green), the nonlinear magnetization (M, black) produces a time-dependent response (red) with distinct higher harmonics. (E) In contrast, a constant magnetic field drives the particles into saturation, yielding negligible harmonic content for image reconstruction (grey box). Reproduced with permission from Ref. [18]. Copyright 2018 American Chemical Society and from Ref. [10]. Copyright 2005 Springer Nature.](/_ipx/b_%23fff&f_webp&q_100&fit_outside&s_470x317/https://mdpi-res.com/jnt/jnt-06-00032/article_deploy/html/images/jnt-06-00032-g001-550.jpg)
![The homeostasis of periodontal tissue, pathogenesis of chronic periodontitis and roles of the involved cytokines. In a healthy state, local challenge and a mild host immune response are balanced. Both the commensal microbiota and mechanical stimulation caused by mastication participate in the training of local mucosal immunity. In this state, there is an appropriate number of infiltrating neutrophils in the gingival sulcus, as well as some resident immune cells in the gingival tissue, including Th17 cells and innate lymphoid cells. However, if the immune pathogenicity of the local microbiota is elevated by the colonization of keystone pathogens, which over-activate the host immune response, tissue destruction is initiated. The interaction between the microbiota and all host cells leads to the first wave of cytokine secretion (1), which mainly participates in the amplification of the proinflammatory cytokine cascade and the recruitment, activation and differentiation of specific immune cells. In addition, a group of cytokines (2) closely related to the differentiation of a specific subset of lymphocytes are secreted by MNPs and APCs after stimulation by the microbiome. Each of these cell subsets secretes a certain pattern of cytokines, which might act as the positive-feedback factor or direct effector (3), eventually leading to tissue destruction. Reproduced from [22]; Creative Commons Attribution 4.0 International CC BY 4.0 Licence.](/_ipx/b_%23fff&f_webp&q_100&fit_outside&s_281x192/images/placeholder.webp)
