High Intensity Focused Ultrasound for Radiorecurrent Prostate Cancer: A North American Clinical Trial.

PURPOSE: We determined the safety and efficacy of whole gland high intensity focused ultrasound in men with radiorecurrent prostate cancer. MATERIALS AND METHODS: A total of 100 men with clinically localized recurrent prostate cancer at least 2 years after external beam radiation therapy underwent whole gland high intensity focused ultrasound in an open label trial from 2009 to 2012. Treatments were performed at 16 sites, including 14 in the United States and 2 in Canada. The primary end point was the combination of a prostate specific antigen nadir of 0.5 ng/ml or less and negative biopsy at 12 months. Validated questionnaires were administered to monitor changes in urinary and sexual function. RESULTS: Of the 100 treated men, in whom mean age was 70 years (range 53 to 83), 78 completed the 12-month biopsy, which was negative in 63 (81%). Mean prostate specific antigen was 4.9 ng/ml (range 0.4 to 14) and the median Gleason score was 7. The 1-year end point of a prostate specific antigen nadir of 0.5 ng/ml or less plus negative biopsy was achieved in 50 men. During post-trial followup mean prostate specific antigen at 2 years was 1.1 ng/ml (range 0.1 to 17) in 33 patients. Adverse events developed in 91 men through 12 months, which were CTCAE grade 1 in 67, grade 2 in 80 and grade 3 in 20. Treatment related grade 3 adverse events included rectal fistulas in 5 men, which required surgery in 3, osteitis pubis in 3 and hematuria requiring intervention in 3. Treatment related grade 3 adverse events developed early in the trial and appeared related to operator experience. There were no life threatening adverse events or treatment related deaths. CONCLUSIONS: Whole gland high intensity focused ultrasound appears reasonably safe and effective to treat radiorecurrent prostate cancer. The rate of complications, which are potentially severe, was acceptable, especially considering the advanced, refractory nature of the disease and the limited treatment options.

Value of Tracking Biopsy in Men Undergoing Active Surveillance of Prostate Cancer.

PURPOSE: We compared the upgrading rate obtained by resampling precise spots of prostate cancer (tracking biopsy) vs conventional systematic resampling during followup of men on active surveillance. MATERIALS AND METHODS: From 2009 to 2017 in 352 men prostate cancer was Gleason 3 + 3 in 268 and Gleason 3 + 4 in 84 at initial magnetic resonance imaging-ultrasound fusion biopsy. These men subsequently underwent a second fusion biopsy. At the first biopsy session all men underwent 12-core systematic biopsies and, when magnetic resonance imaging visible lesions were present, targeted biopsies. All cancerous sites were recorded electronically. During active surveillance at a second fusion biopsy session 6 to 18 months later tracking and systematic nontracking samples were obtained. The primary outcome measure was an increase in Gleason score (upgrading) at followup sampling, which was stratified by biopsy method. RESULTS: Overall 91 of the 352 men (25.9%) experienced upgrading at the second biopsy during a median 11-month interval. The upgrade rate in the Gleason 3 + 3 and 3 + 4 groups was 26.9% and 22.6%, respectively. The mean number of cores taken at second biopsy was 12.2 ± 3.3 in men with upgrading and 12.4 ± 4.1 in those who remained stable (p not significant). Men with grade 0 to 4 magnetic resonance imaging targets were all upgraded at approximately the same rate of 20% to 30% (p not significant). However, 58.8% of the men with grade 5 magnetic resonance imaging targets were upgraded. Of the 91 upgrades 48 (53%) were detected only by tracking. CONCLUSIONS: The tracking function of magnetic resonance imaging-ultrasound fusion biopsy warrants further study. When specific sites are resampled in men undergoing active surveillance of prostate cancer, upgrading is detected more often than by nontracking biopsy.

Focal Laser Ablation of Prostate Cancer: Feasibility of Magnetic Resonance Imaging-Ultrasound Fusion for Guidance.

PURPOSE: Focal laser ablation is a potential treatment in some men with prostate cancer. Currently focal laser ablation is performed by radiologists in a magnetic resonance imaging unit (in bore). We evaluated the safety and feasibility of performing focal laser ablation in a urology clinic (out of bore) using magnetic resonance imaging-ultrasound fusion for guidance. MATERIALS AND METHODS: A total of 11 men with intermediate risk prostate cancer were enrolled in this prospective, institutional review board approved pilot study. Magnetic resonance imaging-ultrasound fusion was used to guide laser fibers transrectally into regions of interest harboring intermediate risk prostate cancer. Thermal probes were inserted for real-time monitoring of intraprostatic temperatures during laser activation. Multiparametric magnetic resonance imaging (3 Tesla) was done immediately after treatment and at 6 months along with comprehensive fusion biopsy. RESULTS: Ten of 11 patients were successfully treated while under local anesthesia. Mean procedure time was 95 minutes (range 71 to 105). Posttreatment magnetic resonance imaging revealed a confined zone of nonperfusion in all 10 men. Mean zone volume was 4.3 cc (range 2.1 to 6.0). No CTCAE grade 3 or greater adverse events developed and no changes were observed in urinary or sexual function. At 6 months magnetic resonance imaging-ultrasound fusion biopsy of the treatment site showed no cancer in 3 patients, microfocal Gleason 3 + 3 in another 3 and persistent intermediate risk prostate cancer in 4. CONCLUSIONS: Focal laser ablation of prostate cancer appears safe and feasible with the patient under local anesthesia in a urology clinic using magnetic resonance imaging-ultrasound fusion for guidance and thermal probes for monitoring. Further development is necessary to refine out of bore focal laser ablation and additional studies are needed to determine appropriate treatment margins and oncologic efficacy.

Optimizing safety and accuracy of prostate biopsy.

PURPOSE OF REVIEW: The objective of this article is to examine the safety of prostate biopsy and discuss the emerging role of MRI-ultrasound fusion technology in improving diagnostic accuracy. RECENT FINDINGS: Men undergoing prostate biopsy frequently experience minor complications, including hematospermia, hematuria, and infection. Quinolone-resistant bacteria are a growing concern; thus, transperineal access or modification of antibiotic prophylaxis based on local antibiograms is now used to avoid infectious complications.Multiparametric MRI allows visualization of many prostate cancers, and by fusing MRI with real-time ultrasound, a biopsy needle can be directed by a urologist into suspicious regions of interest. Using this new method, detection of clinically significant prostate cancer has increased and the incidence of falsely negative biopsies has decreased. SUMMARY: Prostate biopsy is generally a safe procedure, and with attention to local patterns of antibiotic resistance, infectious complications can be minimized. MRI-ultrasound fusion has significantly improved the accuracy of prostate biopsy, allowing tracking and targeting not previously possible.

Serial Molecular Profiling of Low-grade Prostate Cancer to Assess Tumor Upgrading: A Longitudinal Cohort Study.

BACKGROUND: The potential for low-grade (grade group 1 [GG1]) prostate cancer (PCa) to progress to high-grade disease remains unclear. OBJECTIVE: To interrogate the molecular and biological features of low-grade PCa serially over time. DESIGN, SETTING, AND PARTICIPANTS: Nested longitudinal cohort study in an academic active surveillance (AS) program. Men were on AS for GG1 PCa from 2012 to 2017. INTERVENTION: Electronic tracking and resampling of PCa using magnetic resonance imaging/ultrasound fusion biopsy. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: ERG immunohistochemistry (IHC) and targeted DNA/RNA next-generation sequencing were performed on initial and repeat biopsies. Tumor clonality was assessed. Molecular data were compared between men who upgraded and those who did not upgrade to GG ≥ 2 cancer. RESULTS AND LIMITATIONS: Sixty-six men with median age 64 yr (interquartile range [IQR], 59-69) and prostate-specific antigen 4.9 ng/mL (IQR, 3.3-6.4) underwent repeat sampling of a tracked tumor focus (median interval, 11 mo; IQR, 6-13). IHC-based ERG fusion status was concordant at initial and repeat biopsies in 63 men (95% vs expected 50%, p < 0.001), and RNAseq-based fusion and isoform expression were concordant in nine of 13 (69%) ERG+ patients, supporting focal resampling. Among 15 men who upgraded with complete data at both time points, integrated DNA/RNAseq analysis provided evidence of shared clonality in at least five cases. Such cases could reflect initial undersampling, but also support the possibility of clonal temporal progression of low-grade cancer. Our assessment was limited by sample size and use of targeted sequencing. CONCLUSIONS: Repeat molecular assessment of low-grade tumors suggests that clonal progression could be one mechanism of upgrading. These data underscore the importance of serial tumor assessment in men pursuing AS of low-grade PCa. PATIENT SUMMARY: We performed targeted rebiopsy and molecular testing of low-grade tumors on active surveillance. Our findings highlight the importance of periodic biopsy as a component of monitoring for cancer upgrading during surveillance.

Focal Laser Ablation of Prostate Cancer.

Herein, we describe a case of a 63-year-old male who underwent magnetic resonance imaging (MRI)-guided biopsy of a suspicious lesion in the prostate followed by focal laser ablation. Radical prostatectomy was performed 15 months following focal laser ablation for persistent cancer adjacent to the treatment zone. We provide images from the initial MRI, postablation MRI, and the whole-mount radical prostatectomy specimen. The present case demonstrates the confined, localized effect of focal laser ablation, and also illustrates the advantage of expanded treatment margins.

Targeted Prostate Biopsy Using 68Gallium PSMA-PET/CT for Image Guidance.

Prostate specific membrane antigen (PSMA) scanning is a sensitive method of prostate cancer detection. In a 71 y.o. man with a PSA of 49 (6%F), 4 negative MRI studies and 6 negative biopsies over an 8 year interval, a 68Ga-PSMA PET/CT scan showed a PSMA-avid spot in the prostate. Using image fusion technology, the lesion was target-biopsied and Gleason 3 + 4 = 7 (cancer core length of 12 mm) was identified. This case may herald a new application for PSMA scanning and prostate cancer imaging.