E. David Crawford, MD, presents “PET Tumor Board: Case 8 – A Case of An 81-year-old Man with High-risk Prostate Cancer with Initial PSA of 8.4 and a Large Peripheral Zone Lesion.”

How to cite: Crawford, E. David. PET Tumor Board: Case 8 – A Case of An 81-year-old Man with High-risk Prostate Cancer with Initial PSA of 8.4 and a Large Peripheral Zone Lesion. August 15, 2025. Accessed Dec 2025. https://grandroundsinurology.com/pet-tumor-board-case-8/

PET Tumor Board: Case 8 – A Case of An 81-year-old Man with High-risk Prostate Cancer with Initial PSA of 8.4 and a Large Peripheral Zone Lesion – Summary

Why Watch: This multidisciplinary tumor board case illustrates how prostate-specific membrane antigen (PSMA) positron emission tomography (PET) can uncover unexpected disease in prostate cancer—even at very low prostate-specific antigen (PSA) levels. The discussion highlights the challenges of balancing treatment intensity, toxicity, and quality of life in older but physically robust patients.

In this multidisciplinary prostate cancer tumor board, E. David Crawford, MD, Editor in Chief of Grand Rounds in Urology and Professor of Urology, University of California, San Diego, California, moderates a case discussion featuring an 81-year-old man presenting with high-risk prostate cancer (initial PSA 8.4 ng/mL, Gleason 4+5=9) and MRI evidence of extensive left peripheral zone involvement. Prostate biopsy confirmed disease in 14/16 cores. PSMA PET identified seminal vesicle invasion and pelvic lymph node involvement. He initiated androgen deprivation therapy (ADT) with abiraterone plus prednisone, alongside external beam radiation therapy. Discussion participants include:

  • Wayne G. Brisbane, MD, Assistant Professor of Urology, University of California, Los Angeles, California
  • Sean P. Collins, MD, PhD, Radiation Oncologist, University of South Florida, Tampa, Florida
  • Sherief H. Gamie, MD, PhD, Chief & Director Molecular Imaging and Theranostics Professor of Clinical Radiology, University of California, San Diego, San Diego, California
  • Andrew W. Hahn, MD, Assistant Professor, The University of Texas MD Anderson Cancer Center, Houston, Texas
  • Daniel P. Petrylak, MD, Professor of Medicine (Medical Oncology) and of Urology, Yale School of Medicine, New Haven, Connecticut

Severe fatigue and cardiotoxicity prompted discontinuation of ADT after ~5 months. Despite cessation, his PSA nadired at 0.040 ng/mL. Given profound symptomatic decline, the team debated testosterone supplementation, contingent on PSMA PET to rule out residual disease. Surprisingly, follow-up imaging revealed extensive local recurrence despite PSA <0.1 ng/mL.

Panelists emphasized key teaching points:

  • PSMA PET sensitivity can reveal significant disease even at very low PSA, challenging assumptions about recurrence thresholds.
  • Radiation dosing strategies are discussed retrospectively, suggesting that boosting PSMA-avid sites or combining with brachytherapy might have reduced local recurrence risk.
  • Treatment trade-offs in older patients are noted, with age, physiologic fitness, and tolerance guiding therapy choices.
  • Local salvage options such as cryotherapy, re-biopsy, and MRI guidance were considered for focal salvage.

This case underscores the value of PSMA PET in monitoring, the complexity of ADT intensification in the elderly, and the ongoing need for predictive biomarkers of both efficacy and toxicity.