A new technique using gold-silica nanoparticles to perform ultrafocal photothermal ablation of prostate cancer tumors seems feasible, safe, and relatively free of serious complications or life-altering changes in genitourinary function for men with low- or intermediate-risk localized prostate cancer, according to a recent study.
In a pilot device study published in the Proceedings of the National Academy of Sciences (Aug. 26, 2019 [Epub ahead of print]), researchers reported on 16 patients with low- or intermediate-risk localized prostate cancer who had the gold-silica nanoshell (GSN)-mediated focal laser ablation technique (AuroLase Therapy). The approach involves infusing prostate tumors with biocompatible gold silica nanoshells and performing high-precision laser ablation.
GSN-mediated focal laser ablation successfully eradicated cancer cells in 87.5% of lesions treated at 1 year of follow-up and resulted in about a 42% reduction in patients’ PSAs at 3 months.
Researchers have since completed enrollment for the first 45 patients to test the primary endpoint of tumor ablation—data that will take about 1 year to mature, according to principal investigator and lead author Ardeshir (Art) Rastinehad, DO, of Icahn School of Medicine at Mount Sinai, New York. Dr. Rastinehad invented the technique used in the AuroLase Therapy trial.
“What is really exciting about this research is it is the first human use of nanoparticle-directed photothermal therapy. It has taken 20 years of research to finally make it to human trials, and we are having very promising results. There are endless possibilities for clinical applications in other tumors,” Dr. Rastinehad told Urology Times.
Dr. Rastinehad began his work on the technique as a fellow working at the National Institutes of Health and Philips Healthcare on a transperineal MR/ultrasound fusion-guided biopsy device.
“This biopsy approach allows patients to have a targeted biopsy with little to no risk of infection. It is also a very stable platform that allows the prior biopsy data to be retargeted for treatment. In our study, we used the fusion biopsy information to target specific areas of the prostate—thus creating a focal therapy approach for prostate tumors,” Dr. Rastinehad said.
The next part of the project involved using gold silica nanoshells to target the tumors, creating a tumor-specific ablation site.
“The big difference between laser ablation and AuroLase-mediated ablation is that a typical laser generates heat, which kills tissue. In our study, we use a low-temperature laser that sends light energy through the tissue to excite the Auroshells to create heat and thus kill prostate tumors,” he said.