Title : Sentinel lymph node biopsy for breast cancer in low-resource settings: The role of superparamagnetic iron oxide tracers
Abstract:
Sentinel lymph node biopsy (SLNB) is the standard technique for axillary staging in early breast cancer, allowing accurate nodal assessment while avoiding the morbidity associated with full axillary clearance. However, the conventional SLNB approach, which relies on radioactive tracers in combination with blue dye, is often difficult to implement in low-resource settings (LRS). This is due to limited access to nuclear medicine facilities, regulatory restrictions surrounding radioactive materials, and shortages of trained personnel.
Superparamagnetic iron oxide (SPIO) tracers offer a radiation-free alternative, enabling sentinel lymph node detection using a handheld magnetic probe. This educational poster provides an overview of the principles of SPIO-guided SLNB, compares it with standard radiocolloid-based techniques, and explores its potential role in improving access to breast cancer surgery in LRS.
Compared to radioactive tracers, SPIO offers several practical advantages, including elimination of the need for nuclear infrastructure, simplified storage and handling requirements, and reduced regulatory burden. Additionally, SPIO allows greater flexibility in timing of tracer administration, with injection possible from minutes up to several days prior to surgery. Evidence from clinical studies suggests that SPIO provides detection rates comparable to conventional techniques, while potentially reducing indirect system costs.
Despite these advantages, SLNB remains underutilised in LRS. Survey data indicate that only a minority of eligible patients in these settings undergo SLNB, largely due to lack of access to radiocolloid tracers, inadequate infrastructure, and workforce limitations. Additional barriers to widespread SPIO adoption include limited validation in diverse resource-constrained contexts, upfront equipment costs, and the need for training and integration into existing surgical pathways.
Addressing these challenges will require further prospective studies, economic evaluations, and coordinated policy efforts aligned with global initiatives such as the Global Breast Cancer Initiative and national surgical planning frameworks. SPIO-guided SLNB represents a promising strategy to expand access to effective axillary staging in resource-limited environments, with potential to improve surgical outcomes and reduce global disparities in breast cancer care.
