There is no way to identify patients who will harbor small volume, unilateral prostate cancer at final pathology. implications for focal therapies

Extensive disease among potential candidates for hemi-ablative focal therapy for prostate cancer

OBJECTIVE

To examine a set of proposed eligibility factors for hemi-ablative focal therapy in prostate cancer and to determine the likelihood of residual extensive disease.

METHODS

We retrospectively analyzed data from 98 patients with unilateral prostate cancer on biopsy with detailed tumor maps from whole-mount slides and preoperative magnetic resonance imaging data. These patients met the focal therapy consensus meeting inclusion criteria (prostate-specific antigen <15 ng/mL, clinical stage T1c-T2a and Gleason score 3 + 3 or 3 + 4 on needle biopsy), and underwent radical prostatectomy between 2000 and 2014. Extensive disease was defined as having Gleason pattern 4/5 in bilateral lobes, any extraprostatic extension, seminal vesicle invasion or lymph node invasion. Both lobes of the prostate were scored on magnetic resonance imaging. Preoperative characteristics including biopsy and magnetic resonance imaging data were used to predict extensive disease.

RESULTS

Among our cohort of 98 patients, 40% (95% CI 30-50%) had extensive disease. A total of 33% (95% CI 24-43%) had Gleason pattern 4/5 in both lobes with a median Gleason pattern 4/5 tumor volume in the biopsy negative lobe of 0.06 cm³ , 17 patients had pathological tumor stage ≥3 and one patient had lymph node invasion.

CONCLUSIONS

An important number of patients meeting the focal therapy consensus meeting inclusion criteria can present extensive disease. Further studies using targeted biopsies might provide more accurate information about the selection of focal therapy candidates.

Impact of bilateral biopsy-detected prostate cancer on an active surveillance population

BACKGROUND

To assess factors that can predict active surveillance (AS) failure on serial transrectal ultrasound guided biopsies in patients with low-risk prostate cancer.

METHODS

We evaluated the records of 144 consecutive patients enrolled in AS between 2007 and 2014 at a single academic institution. Low risk inclusion criteria included PSA < 10 ng/ml, cT1c or cT2a, Grade Group (GG) 1, < 3 positive cores, and < 50% tumor in a single core with the majority having a PSA density of < 0.15. AS reclassification was defined as progression to GG ≥2, 3 or more cores, or core tumor volume ≥ 50%. Univariate and multivariate Cox proportional hazards regression analysis was used to determine predictors of reclassification and a match-pair analysis performed on a control group of patients choosing surgery.

RESULTS

Inclusion criteria were met by 130 men with a median follow-up of 52 months. The reclassification or AS failure rate was 38.5%, with the majority 41/50 (82%) finding GG ≥ 2 cancer. Most patients had unilateral disease on diagnostic biopsy (94.6%), but 40.7% had bilateral cancer detected during follow-up. Men with bilateral detected tumor were more likely to ultimately fail AS than patients with unilateral tumors (HR 4.089; P < 0.0001) and failed earlier with a reclassification-free survival of 32 vs 119 months respectively. In a matched-pair analysis using a population of 211 concurrent patients that chose radical prostatectomy rather than AS, 76% of patients with unilateral cancer on biopsy had bilateral cancer on final pathology.

CONCLUSIONS

The finding of bilateral prostate cancer on biopsy is associated with earlier AS reclassification. Finding bilateral disease may not represent disease progression, but rather enhanced detection of more extensive disease highlighting the importance of confirmatory biopsy.

Prostate Biopsy in Active Surveillance Protocols: Immediate Re-biopsy and Timing of Subsequent Biopsies

PURPOSE OF REVIEW

This manuscript reviews contemporary literature regarding prostate cancer active surveillance (AS) protocols as well as other tools that may guide the management of biopsy frequency and assess the possibility of progression in low-risk prostate cancer.

RECENT FINDINGS

There is no consensus regarding the timing of surveillance biopsies; however, an immediate repeat biopsy within 12 months of diagnosis for patients considering AS confirms patients who have favorable risk disease yet also identifies patients who were undersampled initially. Studies regarding multiparametric MRI, nomograms, and biomarkers show promise in risk stratifying and counseling patients during AS. Further studies are needed to determine if these supplemental tests can decrease the frequency of surveillance biopsies. An immediate re-biopsy can help to reduce the risk of missing clinically significant disease. Other clinical tools, including mpMRI, exist that can be used as an adjunct to counsel patients and guide a personalized discussion regarding the frequency of surveillance biopsies.

Twelve Core Template Prostate Biopsy is an Unreliable Tool to Select Patients Eligible for Focal Therapy

Introduction: To determine whether unilateral prostate cancer diagnosed at 12-core prostate biopsy harbours relevant prostate cancer foci in contralateral lobe in cases eligible for hemiablative focal therapy. Material and Methods: We analysed 112 radical prostatectomies of unilateral Gleason 6/7 prostate cancer based on prostate biopsy information. The presence of significant prostate cancer foci and/or the index lesion in the contralateral lobe is described. A subanalysis is performed in cases of Gleason score 6 and in cases of very-low-risk prostate cancer. Results: Contralateral prostate cancer was present in 69.6% of cases, fulfilling significant prostate cancer criteria in 33% and being the index lesion in 32%. No significant differences were found when analysing the Gleason 6 group (73% contralateral prostate cancer, 34% significant prostate cancer and 35% index lesion) or the very-low-risk prostate cancer group (80% contralateral prostate cancer, 29% significant prostate cancer and 45% index lesion). Conclusions: The assumption of unilateral prostate cancer based on 12-core template prostate biopsy information is unreliable. In about one third of the cases, there will be focus of significant prostate cancer or the index lesion in the contralateral lobe. This information should be taken into account when hemiablative focal therapies are considered.

Perspectives on the clinical management of localized prostate cancer

If cure is necessary, is it possible and if cure is possible, is it necessary?’

-Willet F. Whitmore

Defined broadly, prostate cancer has two states: An indolent histological manifestation of a locally proliferative and invasive process or a clinically relevant, potentially lethal disease. Likewise, the management of clinically localized prostate cancer must address two questions: what sort of disease is this and what needs to be done.