Faculty Bibliography

Multiparametric MRI of the prostate demonstrates strong potential to address many limitations of traditional prostate cancer diagnosis and management strategies. Recent evidence supports roles for prostate MRI in prebiopsy risk stratification, guidance of targeted biopsy and preoperative disease staging. Prostate MRI may also assist the planning and follow-up of investigational partial gland ablative therapies. This article reviews the impact of prostate MRI on such diagnostic and therapeutic paradigms in contemporary prostate cancer management.

INTRODUCTION: Vascular targeted photodynamic therapy (VTP) with WST11 (TOOKAD(R) Soluble; STEBA Biotech, Luxembourg) is a form of tissue ablation that may be used therapeutically for localized prostate cancer (PCa). To study dosing parameters and associated treatment effects we undertook a prospective multicenter phase I/II trial of WST11 VTP for treatment of PCa METHODS: 30 men with unilateral, low volume, Gleason 3+3 PCa were enrolled at 5 centers following local IRB approval. Light energy, fiber number, and WST11 dose were escalated to identify optimal dosing parameters for VTP hemiablation. Men were treated by VTP and evaluated by post-treatment MRI and biopsy. PSA, light dose index (LDI -defined as sum of fiber length/ desired treatment volume), toxicity, and quality of life parameters were recorded. RESULTS: Following dose escalation, 21 men received optimized dosing of 4 mg/kg WST11 200 J energy. On post-treatment biopsy, residual PCa was found in the treated lobe in 10 men, untreated lobe in 4, and both lobes in 1. When LDI>/=1, at optimal dosing, (n=15), 73.3% had a negative biopsy in the treated lobe. Six men undergoing retreatment, with optimal dose and LDI >/=1, had negative post-treatment biopsy. Minimal effects on urinary, sexual function, and overall quality of life, were observed. CONCLUSIONS: Hemiablation of the prostate with WST11 VTP was well-tolerated and resulted in negative biopsy in the treated lobe for the majority of men. Dosing parameters and LDI appear related to tissue response as determined by MRI and biopsy. These parameters may serve as the basis for further prospective studies.

OBJECTIVES: To evaluate the cancer detection rates (CDR) for men undergoing 12 core systematic prostate biopsy with negative prebiopsy mpMRI (NegMR). MATERIALS & METHODS: Clinical data from consecutive men undergoing prostate biopsy with prebiopsy 3T mpMRI from December 2011 to August 2014 were reviewed from an IRB approved prospective database. Prebiopsy mpMRI was read by a single radiologist and men with NegMR prior to biopsy were identified for this analysis. Clinical features, CDR, and NPV rates were summarized. RESULTS: Seventy five men underwent SPB with a NegMRI during the study period. For the entire cohort, men with no prior biopsy, men with prior negative biopsy, and men enrolled in active surveillance protocols, overall CDR was 18.7%, 13.8%, 8.0% and 38.1%, respectively, and detection of Gleason sum >/= 7 (GS>/=7) cancer was 1.3%, 0%, 4.0% and 0%, respectively. The NPV for all cancers was 81.3%, 86.2%, 92.0%, and 61.9%, and for GS>/=7 cancer was 98.7%, 100%, 96.0% and 100%, respectively. CONCLUSIONS: Negative prebiopsy mpMRI confers an overall NPV of 82% on 12 core biopsy for all cancer and 98% for GS>/=7. Based upon biopsy indication, these findings assist in prebiopsy risk stratification for detection of high risk disease and may provide guidance in the decision to pursue biopsy