Frontiers in Oncologic Prostate Care and Ablative Local Therapy Archives

Point Counterpoint: Micro Ultrasound

Posted by Gerald L. Andriole, Jr., MD | Mar 2024

Gerald L. Andriole, Jr., MD, presents the benefits of including micro ultrasound (microUS) in prostate imaging. He begins by noting that microUS is a relatively new technology compared to multiparametric magnetic resonance imaging (mpMRI).

Dr. Andriole presents examples of the detailed prostate images produced by microUS. He discusses the Prostate Risk Identification using MicroUltraSound (PRIMUS) classification system, intended as an analog to PRI-RADS, and the training required for practitioners using microsUS. He presents video examples of microUS-guided versus MRI-guided biopsies.

He concludes by comparing the specificity, sensitivity, and NPV of mpMRI and microUS biopsies in identifying clinically significant cancer. He presents recent studies which indicate that microUS alone may be as effective as mpMRI alone in the context of biopsies.

Point Counterpoint: MRI

Posted by Thomas P. Frye, DO | Mar 2024

Thomas P. Frye, DO, argues in favor of multiparametric magnetic resonance imaging (mpMRI) over micro ultrasound (MicroUS) for prostate imaging. He begins by stating the underlying goals of prostate imaging in the context of triaging in urologic oncology.

Dr. Frye then turns to the lack of data in support of microUS over mpMRI. He highlights that prostate imaging from MicroUS lacks the scale and reliable interpretability of mpMRI.

Dr. Frye supports the effectiveness of mpMRI in detecting clinically significant prostate cancer with data from the PROMIS and PRECISION studies. He notes that the use of mpMRI in screening can prevent unnecessary biopsies of insignificant cancers.

He concludes by reviewing weaknesses in recent studies of mircoUS. He presents a clinical analysis of microUS which demonstrated the superiority of conventional imaging (TRUS) and mpMRI over microUS.

PSMA PET for Prostate Cancer: Primary Staging, Recurrent Disease Localization

Posted by Steven P. Rowe, MD, PhD | Mar 2024

Steven P. Rowe, MD, PhD, discusses the strengths of Prostate-Specific Membrane Antigen (PSMA) PET in PCa staging and localization. Dr. Rowe begins with a brief overview of PSMA PET and its correlation with metastases and tumor aggressiveness.

Dr. Rowe focuses on the sensitivity and specificity of PSMA PET for identifying metastases. He establishes that PSMA PET has high specificity, regardless of metastatic tumor size, but that the sensitivity to tumors below 5 millimeters in diameter is low. For treatment of the primary disease in the prostate, Dr. Rowe discusses the role of PSMA PET in tumor segmentation.

Dr. Rowe concludes by addressing the use of PSMA PET in identifying recurrent disease and salvage therapy candidates. He discusses the design and results of the CONDOR trial, and the lesion-level positive predictive value of PSMA PET in recurrent disease.

Prostate MRI for Dummies

Posted by Sadhna Verma, MD, FSAR | Feb 2024

Sadhna Verma, MD, FSAR, presents an overview of the use of multiparametric MRI in evaluating the prostate. Dr. Verma begins by reviewing the three elements of a multiparametric MRI in prostate cancer treatment: T2 Weighted Imaging (T2W), Diffusion Weighted Imaging (DWI), and Dynamic Contrast Enhanced (DCE) Imaging.

Dr. Verma presents examples of T1 and T2 Weighted (T2W) MRI images, which are used to illustrate the zonal anatomy of the prostate. She notes that T1 and T2 MRI is weak when it comes to identifying problems in the transition zone.

Dr. Verma then moves to Diffusion Weighted Imaging (DWI) to measure cell diffusion as a means of locating tumors. However, she notes that DWI is not very accurate for recently-biopsied patients.

Dr. Verma concludes by briefly touching on Dynamic Contrast Enhanced (DCE) Imaging to measure tumor vascularity, and how DCE combines with T2W and DWI to give each identified lesion a PI-RADS (Prostate Imaging Reporting and Data System) score. She emphasizes that a PI-RADS score should only be used in detection of clinically significant prostate cancer, and presents examples of how prostate cancer can be identified in peripheral zones, transition zones, and extra-prostatic locations through the use of multiparametric MRI.

Radiopharmaceuticals in Advanced Prostate Cancer

Posted by Steven P. Rowe, MD, PhD | Jan 2024

Steven P. Rowe, MD, PhD, delves into the transformative potential and challenges of radioligand therapy in managing advanced prostate cancer. In this 21-minute presentation, Dr. Rowe emphasizes the excitement surrounding the efficacy and tolerability of agents like lutetium PSMA-617, contrasting them with harsher cytotoxic treatments. A nuanced discussion addresses pitfalls in PSMA PET imaging, highlighting false positives and underscoring the necessity of careful interpretation.

Toxicity management and manageable side effects are discussed. Innovations in imaging biomarkers and longitudinal PSMA PET imaging are positioned as tools to refine response assessment and personalize therapy.

Given differences in training and systemic constraints, challenges in translating European advancements to US practice are acknowledged. Further, Dr. Rowe critiques limitations in AI and radiomics applications for PET scans, highlighting the inability to characterize findings accurately. Ultimately, Dr. Rowe advocates integrating PSMA PET into clinical trials and enhancing therapy stratification to maximize patient benefit.