He went on to complete his chief residency at Yale and then completed a two year clinical complex surgical oncology fellowship at the prestigious and consistently ranked #1 Cancer Center in the United States, University of Texas MD Anderson Cancer Center in Houston, Texas where he spent an additional year doing a post-doctoral research fellowship under the mentorship of Drs. Rosenberg where he was co-investigator on numerous clinical trials. Prieto, completed his general surgery residency at Yale University School of Medicine where he took three years off and completed a surgical oncology research fellowship and a one of its kind immunotherapy fellowship in the surgery branch of the National Cancer Institute, National Institutes of Health under the mentorship of Dr. Prieto chose to dedicate his life to conquering cancer after losing his father to sarcoma.
