ESCAPE - Evaluation of Prostate Specific Membrane Antigen Positron Emission Tomography-Computed Tomography in Active Surveillance for Prostate Cancer

Prostate cancer (PCa) shows a striking degree of clinical variability, with most aging men harboring indolent, low risk PCa that will not threaten their health during their natural lifetime. Definitive treatment for these indolent, low risk cancers with surgery or radiation therapy (RT) risks unnecessary

cost and treatment-related toxicity. Because of this, active surveillance (AS), a management strategy that avoids or defers treatment, has emerged as a standard of care for low risk PCa. AS consists of monitoring low risk, clinically insignificant PCa patients, with treatment with curative intent ONLY with

progression to clinically significant PCa (csPCa). Determining when a patient progresses on AS consists a variable mix of serial prostate specific antigen (PSA) measurements, imaging, and prostate biopsies . However, no consensus exists as to the ideal set of tests and monitoring frequencies during AS. Prostate biopsy itself has measurable morbidity and is associated with infection, urinary

retention, pain and worsening of urinary symptoms. There is therefore a need for optimization of AS protocols and to improve the detection of csPCa for men on AS. Prostate imaging with magnetic resonance imaging (MRI) has become an integral tool in the diagnosis of PCa and monitoring of men on AS as it improves the detection of clinically significant PCa compared to prostate biopsy without

MRI targeting, however accuracy is limited. A negative MRI still misses approximately 20% of csPCa and a positive MRI will result in a negative biopsy 50% of the time. Better imaging is required to improve the detection of csPCa. Prostate Specific Membrane Antigen Positron Emission Tomography-Computed Tomography (PSMA-PET CT) is the most sensitive technique available for

detection of metastatic prostate cancer. The accuracy of PSMA-PET CT in localized disease is limited; however, it has been shown that PSMA-PET CT adds diagnostic value to prostate MRI for detection of csPCa, specifically improving negative predictive value. We hypothesize that PSMA-PET CT in AS patients will improve diagnostic accuracy of prostate MRI such that a negative study will

obviate the need for surveillance prostate biopsy. The Evaluation of Prostate Specific Membrane Antigen Positron Emission Tomography-Computed Tomography in Active Surveillance for Prostate CancEr (ESCAPE) trial is a single arm, prospective multi-institutional clinical trial assessing the negative predictive value of PSMA PET CT in detecting clinically significant prostate cancer. We

hypothesize that PSMA-PET CT can rule out clinically significant prostate in AS patients due to its high negative predictive value.