A first-in-human phase I imaging study using hyperpolarized 1 c-13 pyruvate (h-Py) in patients (pts) with localized prostate cancer (l-PCa)

• Published in: Journal of clinical oncology Vol. 30; no. 15_suppl; p. 4660
• Main Authors: Harzstark, Andrea Lynne, Weinberg, Vivian K., Grycz, Krystyna, Hurd, Ralph E., Ardenkjaer-Larsen, Jan Henrik, Murray, Jonathan, Chen, Albert, Ferrone, Marcus, Park, Ilwoo, Reed, Galen, Munster, Pamela N., Small, Eric Jay, Carvajal, Lucas E., VanCriekinge, Mark E., Larson, Peder E., Chang, Jose, Bok, Robert A., Nelson, Sarah J., Vigneron, Daniel B., Kurhanewicz, John V.
• Format: Journal Article
• Language: English
• Published: 20.05.2012
• ISSN: 0732-183X; 1527-7755
• DOI: 10.1200/jco.2012.30.15_suppl.4660

Abstract only 4660 Background: Preclinical studies demonstrated that the conversion of h-Py to hyperpolarized 13 C lactate (h-lac) is detectable on MRI-spectroscopy and is a useful marker of differentiation in PCa. H-Py MRI provides more than 10,000-fold enhancement in signal to noise ratio (SNR), allowing for rapid detection of metabolic alterations in vivo. Hyperpolarized compounds have not been previously studied in man. Methods: Pts with biopsy-proven untreated l-PCa were enrolled in a phase I study of h-Py MRI. Following a modified 3+3 design, 6 pts were enrolled at each dose level (0.14, 0.28 and 0.43 mL/Kg): 3 to monitor kinetics of h-Py, and 3 to evaluate the spatial distribution of metabolism in PCa and normal prostate (nl-P). An expansion cohort of 15 pts explored the biological variability of metabolism. A dynamic nuclear polarization (DNP) system, the first human system anywhere, generated and delivered 230 mM sterile h-Py. IV injection of h-Py was followed by imaging with a 3T MR scanner with custom transmit and receive coils. Monitoring included EKG, vital signs, and laboratory testing. Results: 31 pts were imaged. 23 pts had Gleason (G) 6, 6 pts G7, and 2 pts G8 PCa. Median age was 63 years (range 45-75); median PSA was 5.9 ng/mL (1.88-20.2). No dose limiting toxicities or >grade (gr) 2 toxicity was observed. Toxicity included: gr 1dysgeusia (6 pts), gr 1 hypokalemia, gr 1 hypocalcemia, gr 1 dizziness, and gr 2 diarrhea (1 pt each). Median time from dissolution of the agent to delivery into patients was 66 seconds (43-88). Signals from h-Py and h-Lac were seen in PCa and nl-P at all doses; 0.43 mL/Kg showed the best SNR and discrimination between PCa and nl-P and was therefore established as the phase II dose. There appeared to be an association between h-Lac levels and PCa grade. Conclusions: H-py metabolic imaging has minimal toxicity and provides the ability to discriminate Ca from nl-P based on increased levels of h-lac. The correlation with grade and changes with therapy require further study.