Multicenter clinical trial on sentinel lymph node biopsy using superparamagnetic iron oxide nanoparticles and a novel handheld magnetic probe

Abstract

Background Sentinel lymph node biopsy is a standard staging procedure for early axillary lymph node‐negative breast cancer. As an alternative to the currently used radioactive tracers for sentinel lymph node (SLN) detection during the surgical procedure, a number of studies have shown promising results using superparamagnetic iron oxide (SPIO) nanoparticles. Here, we developed a new handheld, cordless, and lightweight magnetic probe for SPIO detection. Methods Resovist (SPIO nanoparticles) were detected by the newly developed handheld probe, and the SLN detection rate was compared to that of the standard radioisotope (RI) method using radioactive colloids (99mTc) and a blue dye (indigo carmine). This was a multicenter prospective clinical trial that included 220 patients with breast cancer scheduled for sentinel node biopsy after a clinical diagnosis of negative axillary lymph node from three facilities in Japan. Results Of the 210 patients analyzed, SLN was detected in 94.8% (199/210 cases, 90% confidence interval [CI]) with our magnetic method and in 98.1% (206/210 cases, 90% CI) with the RI method. The magnetic method exceeded the threshold identification rate of 90%. Conclusion This was the first clinical study to use a novel handheld magnetometer to detect SLN, which we demonstrate to be not inferior to the RI method.

Challenges in the development of nanoparticle‐based imaging agents: Characterization and biology

“…administration, and they can be further tuned towards lymph node accumulation (Schudel, Francis, & Thomas, 2019). This nanoparticle‐based lymphatic imaging has been used to monitor the impact of disease upon the lymphatic system, as well as identify sentinel lymph nodes in cancer (Müller et al, 2017; Taruno et al, 2019). As discussed previously in this review, nanoparticles also have a tendency to be taken up by immune cells, and therefore it is not surprising that nanotechnology‐based imaging agents are in development for imaging inflammation associated with disease states.…”

Accuracy of Magnetometer-Guided Sentinel Lymphadenectomy after Intraprostatic Injection of Superparamagnetic Iron Oxide Nanoparticles in Prostate Cancer: The SentiMag Pro II Study

“…Another limitation of the magnetic technique is the maximum depth at which the magnetic signal can be detected. Currently available handheld magnetometers do not reach the same depth as a gamma probe (e.g., SentiMag:~20 mm; TAKUMI ® magnetic probe: 10 mm), which can have consequences for the identification of deeper nodes [22,23]. In the MELAMAG Trial, patients with melanoma who underwent SentiMag-guided SLN biopsy in the axillary basin had a lower SLN identification rate than those who required SLN biopsy in the groin basin, seemingly owing to SLNs being located deeper in the axilla compared with the groin [23].…”

“…Another important advantage for routine clinical use of the magnetic sentinel method is that this non-radioactive procedure does not require a radiation-controlled area or imaging facilities and can be safely implemented without facilities' restrictions in large parts of the world. For example, in Japan, currently, approximately 30% of the facilities do not have a radiation-controlled area [22]. Furthermore, SPION tracer is retained in LNs for a longer time, allowing for delayed sLND (up to 7 days for Sienna+ in breast cancer), which facilitates the patient planning.…”

Nanomedicine Interventions in Clinical Trials for the Treatment of Metastatic Breast Cancer

“…The use of nanomedicine in cancer therapy has opened up new possibilities for more precise drug-delivery systems with fewer associated side-effects, and for more information on the impact of nanomedicine in the treatment of cancer, the reader can consult the following literature [5]. In particular, the authors highlight superparamagnetic iron oxide nanoparticles (SPIONs) that seem to have the potential for synergy with other methods of cancer therapy, including those discussed in this review [13][14][15]. However, since these technologies have not yet been introduced in clinical trials, they will not be discussed in this paper.…”