(UroToday.com) The 2025 ASCO annual meeting featured a prostate cancer session and a presentation by Dr. Ravi Madan discussing preliminary data from 6 month follow-up assessing prospective monitoring of PSMA–positive biochemically recurrent prostate cancer. PSMA imaging can identify recurrent prostate cancer after definitive surgery/radiation prior to detection on CT or bone scan, and radiation to PSMA positive findings is common but lacks clear data demonstrating long term benefit. PSMA positive biochemically recurrent prostate cancer is often defined and treated as metastatic castration sensitive prostate cancer (mCSPC), yet PSMA imaging alone as an eligibility criteria were never studied in the mCSPC trials. Thus, PSMA–positive biochemically recurrent prostate cancer requires a better understanding to define at-risk patients.
The NCT05588128 study enrolls patients after definitive and possibly salvage therapies. Patients are required to be one year removed from definitive therapy with a PSA >0.5 ng/ml, testosterone >100 ng/dL, and negative CT/bone scans. Lymph nodes up to 1.5 cm and prior therapies are permitted. At enrollment, patients have a baseline PSMA, which is repeated every 6 months if positive. If negative, a PSMA is done annually; CT and bone scan are also repeated annually. Patients are allowed to have radiation therapy or systemic therapies for ≤6 months and remain on-study. Up to 350 patients will be enrolled in this study and followed for up to 5 years
Over 120 patients have enrolled since March 2023, and 86 patients were evaluable after the 6-month PSMA scan/follow-up. The patients have a median age of 71 years, median PSA of 3.05 ng/mL, and median PSA doubling time of 11.1 month (29% less than 6 month). In an overlapping descriptive analysis, 10 patients were PSMA negative, and 17 patients had only local disease.
For PSMA positive lymph nodes, 17 patients had one positive lymph node, 9 patients had 2-3 lymph nodes positive, 5 patients had 4 lymph nodes positive, and 18 patients had 5+ positive lymph nodes. There were 7 patients that had bone findings, but negative bone scan, 4 patients had PSMA positive serosal nodules, and 4 patients had radiation to solitary lymph nodes. There was one patient who elected for ADT, and one patient had salvage radiation. Overall, 4 patients enrolled in a clinical study at the NCI without ADT. At the 6 month PSMA scan, only one patient had metastatic disease (bone scan findings), no patients had lymph nodes beyond eligibility size criteria, and no patients had new visceral findings.
Dr. Madan concluded his presentation discussing preliminary data from 6 month follow-up assessing prospective monitoring of PSMA–positive biochemically recurrent prostate cancer with the following take home points:
- These preliminary data from an ongoing study suggest PSMA positive biochemically recurrent prostate cancer is an indolent disease process, and patients are at limited risk for clinically relevant progression within 6 months
- This study continues to accrue at the NCI and will seek to better define high risk PSMA–positive biochemically recurrent prostate cancer
- These preliminary data may better inform the risk/benefits of aggressive treatment of PSMA–positive biochemically recurrent prostate cancer and clinical studies in PSMA–positive biochemically recurrent prostate cancer
Presented by: Ravi Madan, MD, National Cancer Institute, National Institutes of Health, Bethesda, MD
Written by: Zachary Klaassen, MD, MSc – Urologic Oncologist, Associate Professor of Urology, Georgia Cancer Center, Wellstar MCG Health, @zklaassen_md on Twitter during the American Society of Clinical Oncology (ASCO) 2025 Annual Meeting, Chicago, IL, Fri, May 30 – Tues, Jun 3, 2025.
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