Defining the level of evidence for technology adoption in the localized prostate cancer pathway

Prostate Imaging Compared to Transperineal Ultrasound-guided biopsy for significant prostate cancer Risk Evaluation (PICTURE): a prospective cohort validating study assessing Prostate HistoScanning

BACKGROUND

Men with negative prostate biopsies or those diagnosed with low-risk or low-volume intermediate-risk prostate cancers often require a second prostate biopsy prior to a treatment decision. Prostate HistoScanning (PHS) is an ultrasound imaging test that might inform prostate biopsy in such men.

METHODS

PICTURE was a prospective, paired-cohort validating trial to assess the diagnostic accuracy of imaging in men requiring a further biopsy (clinicaltrials.gov, NCT01492270) (11 January 2012-29 January 2014). We enrolled 330 men who had undergone a prior TRUS biopsy but where diagnostic uncertainty remained. All eligible men underwent PHS and transperineal template prostate mapping (TTPM) biopsy (reference standard). Men were blinded to the imaging results until after undergoing TTPM biopsies. We primarily assessed the ability of PHS to rule out clinically significant prostate (negative predictive value [NPV] and sensitivity) for a target histological condition of Gleason ≥4+3 and/or a cancer core length (MCCL) ≥6 mm. We also assessed the role of visually estimated PHS-targeted biopsies.

RESULTS

Of the 330 men enrolled, 249 underwent both PHS and TTPM biopsy. Mean (SD) age was 62 (7) years, median (IQR) PSA 6.8 (4.98-9.50) ng/ml, median (IQR) number of previous biopsies 1 (1-2) and mean (SD) gland size 37 (15.5) ml. One hundred and forty six (59%) had no clinically significant cancer. PHS classified 174 (70%) as suspicious. Sensitivity was 70.3% (95% CI 59.8-79.5) and NPV 41.3% (95% CI 27.0-56.8). Specificity and positive predictive value (PPV) were 14.7% (95% CI 9.1-22.0) and 36.8% (95% CI 29.6-44.4), respectively. In all, 213/220 had PHS suspicious areas targeted with targeting sensitivity 13.6% (95% CI 7.3-22.6), specificity 97.6% (95% CI 93.1-99.5), NPV 61.6% (95% CI 54.5-68.4) and PPV 80.0% (95% CI 51.9-95.7).

CONCLUSIONS

PHS is not a useful test in men seeking risk stratification following initial prostate biopsy.

Partial Gland Ablation for Prostate Cancer: Report of a Food and Drug Administration, American Urological Association, and Society of Urologic Oncology Public Workshop

OBJECTIVE

To summarize the discussion that took place at a public workshop, co-sponsored by the U.S. Food and Drug Administration, the American Urological Association, and Society of Urologic Oncology reviewing the current state of the art for partial gland ablation (PGA) for the management of patients with prostate cancer. The purpose of this workshop was to discuss potential indications, current available evidence, and designs for future trials to provide the evidence needed by patients and providers to decide how and when to use PGA.

METHODS

A workshop evaluating PGA for prostate cancer was held in New Orleans, Louisiana, in May 2015. Invited experts representing all stakeholders and attendees discussed the regulatory development of medical products, technology available, potential indications, and designs of trials to evaluate this modality of therapy.

RESULTS

The panel presented the current information on the technologies available to perform PGA, the potential indications, and results of prior consensus conferences. Use of magnetic resonance imaging for patient selection, guide therapy, and follow-up was discussed. Designs of trials to assess PGA outcomes were discussed.

CONCLUSION

The general consensus was that currently available technologies are capable of selective ablation with reasonable accuracy, but that criteria for patient selection remain debatable, and long-term cancer control remains to be established in properly designed and well-performed prospective clinical trials. Concerns include the potential for excessive, unnecessary use in patients with low-risk cancer and, conversely, that current diagnostic techniques may underestimate the extent and aggressiveness of some cancers, leading to inadequate treatment.

Prostate histoscanning true targeting guided prostate biopsy: initial clinical experience

OBJECTIVE

To evaluate the feasibility of prostate histoscanning true targeting (PHS-TT) guided transrectal ultrasound (TRUS) biopsy.

METHODS

This is a prospective, single center, pilot study performed during February 2013-September 2013. All consecutive patients planned for prostate biopsy were included in the study, and all the procedure was performed by a single surgeon aided by the specialized true targeting software. Initially, the patients underwent PHS to map the abnormal areas within the prostate that were ≥0.2 cm(3). TRUS guided biopsies were performed targeting the abnormal areas with a specialized software. Additionally, routine bisextant biopsies were also taken. The final histopathology of the target cores was compared with the bisextant cores.

RESULTS

A total of 43 patients underwent combined 'targeted PHS guided' and 'standard 12 core systematic' biopsies. The mean volume of abnormal area detected by PHS is 4.3 cm(3). The overall cancer detection rate was 46.5 % (20/43) with systemic cores and target cores detecting cancer in 44 % (19/43) and 26 % (11/43), respectively. The mean % cancer/core length of the PHS-TT cores were significantly higher than the systematic cores (55.4 vs. 37.5 %. p < 0.05). In biopsy naïve patients, the cancer detection rate (43.7 % vs. 14.8 %. p = 0.06) and the cancer positivity of the cores (30.1 vs. 6.8 %. p < 0.01) of target cores were higher than those patients with prior biopsies.

CONCLUSION

PHS-TT is feasible and can be an effective tool for real-time guidance of prostate biopsies.

Multiparametric MRI in the PSA screening era

Prostate cancer remains significant public health concern amid growing controversies regarding prostate specific antigen (PSA) based screening. The utility of PSA has been brought into question, and alternative measures are investigated to remedy the overdetection of indolent disease and safeguard patients from the potential harms resulting from an elevated PSA. Multiparametric MRI of the prostate has shown promise in identifying patients at risk for clinically significant disease but its role within the current diagnostic and treatment paradigm remains in question. The current review focuses on recent applications of MRI in this pathway.