Surveillance nanotechnology for multi-organ cancer metastases

The identification and molecular profiling of early metastases remains a major challenge in cancer diagnostics and therapy. Most in vivo imaging methods fail to detect small cancerous lesions, a problem that is compounded by the distinct physical and biological barriers associated with different metastatic niches. Here, we show that intravenously injected rare-earth-doped albumin-encapsulated nanoparticles emitting short-wave infrared light (SWIR) can detect targeted metastatic lesions in vivo, allowing for the longitudinal tracking of multi-organ metastases. In a murine model of human breast cancer, the nanoprobes enabled whole-body SWIR detection of adrenal-gland microlesions and bone lesions that were undetectable via contrast-enhanced magnetic resonance imaging as early as three and five weeks post-inoculation, respectively. Whole-body SWIR imaging of nanoprobes functionalized to differentially target distinct metastatic sites and administered to a biomimetic murine model of human breast cancer resolved multi-organ metastases that showed varied molecular profiles in the lungs, adrenal glands and bones. Real-time surveillance of lesions in multiple organs should facilitate pre- and post-therapy monitoring in preclinical settings.