Comparison of the treatment outcomes: percent change in the sum of longest diameters (RECIST) and percent change of the lesion with the highest SUL (PERCIST) between standard therapy plus Lu-177 PSMA ligand therapy and standard therapy alone among patients with prostatic cancer status-post castration using Ga-18 PET-CT as an outcome indicator

ABSTRACT

Introduction@#Prostate cancer is the third most common cancer among Filipino males. Ga-68 PSMA PET-CT and Lu-177 PRLT have been introduced in the Philippines for the diagnostics and therapy of prostate cancer. @*Objective@#The aim of this study is to compare treatment outcomes of standard therapy plus Lu-177 PSMA radioligand therapy and standard therapy alone among patients with prostatic cancer status-post castration using Ga-68 PET-CT as an outcome indicator. @*Methodology@#This is an ambispective cohort study on Ga-68 PSMA PET-CT scans performed between January 1, 2018 and July 31, 2021. Serum PSA data taken within one month of the PET-CT scans were also collected when available. The PET-CT images were reviewed by a radiologist for RECIST response, and by a nuclear medicine physician for PERCIST response . @*Results@#A total of 11 participants were included in the study. Six participants (55.5%) received standard therapy, while five participants (45.5%) received Lu-177 PSMA radioligand therapy plus standard therapy. There was no significant difference in the baseline and follow-up CT as shown by all p values > 0.05. A trend towards higher number of participants with non-complete/non-progressive RECIST response was noted in the control group than the treatment group, as well as higher number of participants with progressive or stable disease using the PERCIST response. @*Conclusion@#There were no significant differences noted in the clinical outcomes of participants who received Lu-177 PRLT and those with standard therapy alone. A trend towards decreasing serum PSA, CT and PET measurements were noted among patients given Lu-177 PRLT than those with standard therapy.