In the fight against a broad spectrum of human diseases, cavitation techniques show great promise for overcoming physical barriers that lead to suboptimal uptake of passively administered therapeutics. However, small animal testing of candidate therapies remains a poor predictor of clinical success. Here we demonstrate ultrasound-mediated drug delivery in normal and tumour-bearing human livers infused with protein-based cavitation nuclei (PCaN). Whole and partial human livers were obtained immediately from hepatectomy surgeries and were normothermically sustained using a clinically approved perfusion system (OrganOx Metra). Ultrasound was applied using a 0.5 MHz focused source (Sonic Concepts H107) and was monitored with a calibrated linear array (ATS L7-4) for real time structural and cavitational imaging implemented on an array controller (Verasonics Vantage 256). Specifically, the therapy process was monitored using passive acoustic mapping (PAM) of broadband cavitation emissions, employing a non-adaptive beamformer that deconvolves the array point spread function. Levels of fluorescently labelled drugs incorporated in and co-administered with the PCaN were quantified in blood and tissue samples collected during and following treatment, respectively. This presentation highlights PAM observations of broadband cavitation persistence and drug delivery in untargeted and targeted tissues, including the first ever experiments in tumour-bearing human livers.
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