Role of Genetic Testing for Inherited Prostate Cancer Risk: Philadelphia Prostate Cancer Consensus Conference 2017

Purpose Guidelines are limited for genetic testing for prostate cancer (PCA). The goal of this conference was to develop an expert consensus-driven working framework for comprehensive genetic evaluation of inherited PCA in the multigene testing era addressing genetic counseling, testing, and genetically informed management. Methods An expert consensus conference was convened including key stakeholders to address genetic counseling and testing, PCA screening, and management informed by evidence review. Results Consensus was strong that patients should engage in shared decision making for genetic testing. There was strong consensus to test HOXB13 for suspected hereditary PCA, BRCA1/2 for suspected hereditary breast and ovarian cancer, and DNA mismatch repair genes for suspected Lynch syndrome. There was strong consensus to factor BRCA2 mutations into PCA screening discussions. BRCA2 achieved moderate consensus for factoring into early-stage management discussion, with stronger consensus in high-risk/advanced and metastatic setting. Agreement was moderate to test all men with metastatic castration-resistant PCA, regardless of family history, with stronger agreement to test BRCA1/2 and moderate agreement to test ATM to inform prognosis and targeted therapy. Conclusion To our knowledge, this is the first comprehensive, multidisciplinary consensus statement to address a genetic evaluation framework for inherited PCA in the multigene testing era. Future research should focus on developing a working definition of familial PCA for clinical genetic testing, expanding understanding of genetic contribution to aggressive PCA, exploring clinical use of genetic testing for PCA management, genetic testing of African American males, and addressing the value framework of genetic evaluation and testing men at risk for PCA-a clinically heterogeneous disease.

The Melbourne Consensus Statement on the early detection of prostate cancer

Various conflicting guidelines and recommendations about prostate cancer screening and early detection have left both clinicians and their patients quite confused. At the Prostate Cancer World Congress held in Melbourne in August 2013, a multidisciplinary group of the world's leading experts in this area gathered together and generated this set of consensus statements to bring some clarity to this confusion. The five consensus statements provide clear guidance for clinicians counselling their patients about the early detection of prostate cancer.

Using a population-based observational cohort study to address difficult comparative effectiveness research questions: the CEASAR study

BACKGROUND

While randomized controlled trials represent the highest level of evidence we can generate in comparative effectiveness research, there are clinical scenarios where this type of study design is not feasible. The Comparative Effectiveness Analyses of Surgery and Radiation in localized prostate cancer (CEASAR) study is an observational study designed to compare the effectiveness and harms of different treatments for localized prostate cancer, a clinical scenario in which randomized controlled trials have been difficult to execute and, when completed, have been difficult to generalize to the population at large.

METHODS

CEASAR employs a population-based, prospective cohort study design, using tumor registries as cohort inception tools. The primary outcome is quality of life after treatment, measured by validated instruments. Risk adjustment is facilitated by capture of traditional and nontraditional confounders before treatment and by propensity score analysis.

RESULTS

We have accrued a diverse, representative cohort of 3691 men in the USA with clinically localized prostate cancer. Half of the men invited to participate enrolled, and 86% of patients who enrolled have completed the 6-month survey.

CONCLUSION

Challenging comparative effectiveness research questions can be addressed using well-designed observational studies. The CEASAR study provides an opportunity to determine what treatments work best, for which patients, and in whose hands.

Evaluating the Four Kallikrein Panel of the 4Kscore for Prediction of High-grade Prostate Cancer in Men in the Canary Prostate Active Surveillance Study

BACKGROUND

Diagnosis of Gleason 6 prostate cancer can leave uncertainty about the presence of undetected aggressive disease.

OBJECTIVE

To evaluate the utility of a four kallikrein (4K) panel in predicting the presence of high-grade cancer in men on active surveillance.

DESIGN, SETTING, AND PARTICIPANTS

Plasma collected before the first and subsequent surveillance biopsies was assessed for 718 men prospectively enrolled in the multi-institutional Canary PASS trial. Biopsy data were split 2:1 into training and test sets. We developed statistical models that included clinical information and either the 4Kpanel or serum prostate-specific antigen (PSA).

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

The endpoint was reclassification to Gleason ≥7. We used receiver operating characteristic (ROC) curve analyses and area under the curve (AUC) to assess discriminatory capacity, and decision curve analysis (DCA) to report clinical net benefit.

RESULTS AND LIMITATIONS

Significant predictors for reclassification were 4Kpanel (odds ratio [OR] 1.54, 95% confidence interval [CI] 1.31-1.81) or PSA (OR 2.11, 95% CI 1.53-2.91), ≥20% cores positive (OR 2.10, 95% CI 1.33-3.32), two or more prior negative biopsies (OR 0.19, 95% CI 0.04-0.85), prostate volume (OR 0.47, 95% CI 0.31-0.70), and body mass index (OR 1.09, 95% CI 1.04-1.14). ROC curve analysis comparing 4K and base models indicated that the 4Kpanel improved accuracy for predicting reclassification (AUC 0.78 vs 0.74) at the first surveillance biopsy. Both models performed comparably for prediction of reclassification at subsequent biopsies (AUC 0.75 vs 0.76). In DCA, both models showed higher net benefit compared to biopsy-all and biopsy-none strategies. Limitations include the single cohort nature of the study and the small numbers; results should be validated in another cohort before clinical use.

CONCLUSIONS

The 4Kpanel provided incremental value over routine clinical information in predicting high-grade cancer in the first biopsy after diagnosis. The 4Kpanel did not add predictive value to the base model at subsequent surveillance biopsies.

PATIENT SUMMARY

Active surveillance is a management strategy for many low-grade prostate cancers. Repeat biopsies monitor for previously undetected high-grade cancer. We show that a model with clinical variables, including a panel of four kallikreins, indicates the presence of high-grade cancer before a biopsy is performed.

Routine Use of Magnetic Resonance Imaging for Early Detection of Prostate Cancer Is Not Justified by the Clinical Trial Evidence

Guidelines now recommend multiparametric magnetic resonance imaging before prostate biopsy in the work-up for patients with elevated prostate specific-antigen. However, use of magnetic resonance imaging for early detection of prostate cancer is not justified by the clinical trial evidence.

PSMA PET applications in the prostate cancer journey: from diagnosis to theranostics

The heterogeneity of prostate cancer has made imaging modalities of crucial importance in this disease. Accurate diagnosis and staging of the volume and extent of disease, especially in advanced and metastatic prostate cancer, can help to tailor the timing and modalities of treatment. While MRI has been effective in the detection of significant prostate cancer, its use in the identification and quantification of extraprostatic disease is limited. This gap is now being filled by PSMA PET. PSMA PET scans have now been shown to have a role in all stages in the prostate cancer journey. Emerging evidence has shown its promise in primary staging, restaging and theranostics. In this paper, we review the evidence for the use of PSMA PET in the various stages of prostate cancer, from initial diagnosis to advanced metastatic disease where other systemic treatments have failed.

Prostate-specific Membrane Antigen and Fluciclovine Transporter Genes are Associated with Variable Clinical Features and Molecular Subtypes of Primary Prostate Cancer

¹⁸F-Fluciclovine-based positron emission tomography (PET) imaging is recommended in the USA for biochemical recurrence (BCR) after prostate cancer treatment. However, prostate-specific membrane antigen (PSMA)-based PET imaging is more common worldwide, supported by international guidelines, and is now approved by the Food and Drug Administration in the USA for initial staging of primary prostate cancer. Little is known about the molecular profiles of lesions detected by PSMA-targeted PET/computed tomography (CT) versus ¹⁸F-fluciclovine PET/CT. We examined the expression of PSMA (FOLH1) and the fluciclovine transporter genes LAT1-4 and ASCT1/2 in a combined cohort of more than 18 000 radical prostatectomy specimens and their associations with clinical outcomes. Expression of PSMA and all but one fluciclovine transporter gene was higher in prostate cancer than in benign tissue. PSMA expression was associated with Gleason score (GS) ≥8 and lymph node involvement (LNI), and had a positive linear correlation with Decipher risk score. By contrast, expression of the fluciclovine transporters LAT2, LAT3, and ASCT2 was negatively associated with GS ≥ 8, LNI, and high Decipher score. The top decile of PSMA expression was associated with poorest metastasis-free survival (MFS), while the bottom deciles of LAT3 and ASCT2 expression were associated with poorest MFS. PATIENT SUMMARY: We measured the expression of genes that encode the targets for two different radiotracers in PET (positron emission tomography) scans of the prostate. We found that PSMA gene expression (PSMA-based tracer) is associated with worse clinical outcomes, while expression of ASCT2, LAT2, and LAT3 genes (fluciclovine tracer) is associated with better outcomes.

Presurgical 68Ga-PSMA-11 Positron Emission Tomography for Biochemical Recurrence Risk Assessment: A Follow-up Analysis of a Multicenter Prospective Phase 3 Imaging Trial

BACKGROUND

In the initial staging of patients with high-risk prostate cancer (PCa), prostate-specific membrane antigen positron emission tomography (PSMA-PET) has been established as a front-line imaging modality. The increasing number of PSMA-PET scans performed in the primary staging setting might be associated with decreases in biochemical recurrence (BCR)-free survival (BCR-FS).

OBJECTIVE

To assess the added prognostic value of presurgical PSMA-PET for BCR-FS compared with the presurgical Cancer of the Prostate Risk Assessment (CAPRA) and postsurgical CAPRA-Surgery (CAPRA-S) scores in patients with intermediate- to high-risk PCa treated with radical prostatectomy (RP) and pelvic lymph node dissection.

DESIGN, SETTING, AND PARTICIPANTS

This is a follow-up study of the surgical cohort evaluated in the multicenter prospective phase 3 imaging trial (n = 277; NCT03368547, NCT02611882, and NCT02919111).

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Each 68Ga-PSMA-11-PET scan was read by three blinded independent readers. PSMA-PET prostate uptake (low vs high), PSMA-PET extraprostatic disease (N1/M1), and CAPRA and CAPRA-S scores were used to assess the risk of BCR. Patients were followed after RP by local investigators using electronic medical records. BCR was defined by a prostate-specific antigen (PSA) level increasing to ≥0.2 ng/ml after RP or initiation of PCa-specific secondary treatment (>6 mo after surgery). Univariate and multivariable Cox models, and c-statistic index were performed to assess the prognostic value of PSMA-PET and for a comparison with the CAPRA and CAPRA-S scores.

RESULTS AND LIMITATIONS

From December 2015 to December 2019, 277 patients underwent surgery after PSMA-PET. Clinical follow-up was obtained in 240/277 (87%) patients. The median follow-up after surgery was 32.4 (interquartile range 23.3-42.9) mo. Of 240 BCR events, 91 (38%) were observed. PSMA-PET N1/M1 was found in 41/240 (17%) patients. PSMA-PET prostate uptake, PSMA-PET N1/M1, and CAPRA and CAPRA-S scores were significant univariate predictors of BCR. The addition of PSMA-PET N1/M1 status to the presurgical CAPRA score improved the risk assessment for BCR significantly in comparison with the presurgical CAPRA score alone (c-statistic 0.70 [0.64-0.75] vs 0.63 [0.57-0.69]; p < 0.001). The C-index of the postsurgical model utilizing the postsurgical CAPRA-S score alone was not significantly different from the presurgical model combining the presurgical CAPRA score and PSMA-PET N1/M1 status (p = 0.19).

CONCLUSIONS

Presurgical PSMA-PET was a strong prognostic biomarker improving BCR-FS risk assessment. Its implementation in the presurgical risk assessment with the CAPRA score improved the performance and reduced the difference with the reference standard (postsurgical CAPRA-S score).

PATIENT SUMMARY

The use prostate-specific membrane antigen positron emission tomography improved the assessment of biochemical recurrence risk in patients with intermediate- and high-risk prostate cancer who were treated with radical prostatectomy and pelvic lymph node dissection.

Time Trends in Use of Radical Prostatectomy by Tumor Risk and Life Expectancy in a National Veterans Affairs Cohort

IMPORTANCE

Guidelines endorse using tumor risk and life expectancy (LE) to select appropriate candidates for radical prostatectomy (RP), recommending against treatment of most low-risk tumors and men with limited LE.

OBJECTIVE

To investigate time trends in the use of RP by tumor risk and Prostate Cancer Comorbidity Index (PCCI) score in a contemporary, nationally representative Veterans Affairs (VA) cohort.

DESIGN, SETTING, AND PARTICIPANTS

This cohort study of 5736 men treated with RP at 8 VA hospitals from January 1, 2000, to December 31, 2017, used a nationally representative, multicenter sample from the VA SEARCH (Shared Equal Access Regional Cancer Hospital) database. Statistical analysis was performed from June 30, 2018, to August 20, 2020.

MAIN OUTCOMES AND MEASURES

Stratified linear and log-linear Poisson regressions were used to estimate time trends in the proportion of men treated with RP across American Urological Association tumor risk and PCCI (a validated predictor of LE based on age and comorbidities) subgroups.

RESULTS

Among 5736 men (mean [SD] age at surgery, 62 [6] years) treated with RP from 2000 to 2017, the proportion of low-risk tumors treated with RP decreased from 51% to 7% (difference, -44%; 95% CI, -50% to -38%). The proportion of intermediate-risk tumors treated with RP increased from 30% to 59% (difference, 29%; 95% CI, 23%-35%), with unfavorable intermediate-risk tumors increasing from 30% to 41% (difference, 11%; 95% CI, 4%-18%) and favorable intermediate-risk tumors decreasing from 61% to 41% (difference, -20%; 95% CI, -24% to -15%). The proportion of high-risk tumors treated with RP increased from 18% to 33% (difference, 15%; 95% CI, 9%-21%). Among men treated with RP, the proportion with the highest PCCI scores of 10 or more (ie, LE <10 years) increased from 4% to 13% (difference, 9%; 95% CI, 4%-14%). Within each tumor risk subgroup, no significant difference in the rate of tumors treated with RP over time was found across PCCI subgroups.

CONCLUSIONS AND RELEVANCE

In this study, the use of RP shifted from low-risk and favorable intermediate-risk to higher-risk prostate cancer. However, its use among men with limited LE appears unchanged across tumor risk subgroups and increased overall.

Asia prostate cancer study (A-CaP Study) launch symposium

The Asian Prostate Cancer (A-CaP) Study is an Asia-wide initiative that has been developed over the course of 2 years. The A-CaP Study is scheduled to begin in 2016, when each participating country or region will begin registration of newly diagnosed prostate cancer patients and conduct prognosis investigations. From the data gathered, common research themes will be identified, such as comparisons among Asian countries of background factors in newly diagnosed prostate cancer patients. This is the first Asia-wide study of prostate cancer and has developed from single country research efforts in this field, including in Japan and Korea. The inaugural Board Meeting of A-CaP was held on December 11, 2015 at the Research Center for Advanced Science and Technology, The University of Tokyo, attended by representatives of all participating countries and regions, who signed a memorandum of understanding concerning registration for A-CaP. Following the Board Meeting an A-CaP Launch Symposium was held. The symposium was attended by representatives of countries and regions participating in A-CaP, who gave presentations. Presentations and a keynote address were also delivered by representatives of the University of California San Francisco, USA, and the Peter MacCallum Cancer Centre, Australia, who provided insight and experience on similar databases compiled in their respective countries.

Report of the Second Asian Prostate Cancer (A-CaP) Study Meeting

The Asian Prostate Cancer (A-CaP) Study is an Asia-wide initiative that has been developed over the course of 2 years. The study was launched in December 2015 in Tokyo, Japan, and the participating countries and regions engaged in preparations for the study during the course of 2016, including patient registration and creation of databases for the purpose of the study. The Second A-CaP Meeting was held on September 8, 2016 in Seoul, Korea, with the participation of members and collaborators from 12 countries and regions. Under the study, each participating country or region will begin registration of newly diagnosed prostate cancer patients and conduct prognostic investigations. From the data gathered, common research themes will be identified, such as comparisons among Asian countries of background factors in newly diagnosed prostate cancer patients. This is the first Asia-wide study of prostate cancer and has developed from single country research efforts in this field, including in Japan and Korea. At the Second Meeting, participating countries and regions discussed the status of preparations and discussed various issues that are being faced. These issues include technical challenges in creating databases, promoting participation in each country or region, clarifying issues relating to data input, addressing institutional issues such as institutional review board requirements, and the need for dedicated data managers. The meeting was positioned as an opportunity to share information and address outstanding issues prior to the initiation of the study. In addition to A-CaP-specific discussions, a series of special lectures was also delivered as a means of providing international perspectives on the latest developments in prostate cancer and the use of databases and registration studies around the world.

Report of the third Asian Prostate Cancer study meeting

The Asian Prostate Cancer (A-CaP) study is an Asia-wide initiative that was launched in December 2015 in Tokyo, Japan, with the objective of surveying information about patients who have received a histopathological diagnosis of prostate cancer (PCa) and are undergoing treatment and clarifying distribution of staging, the actual status of treatment choices, and treatment outcomes. The study aims to clarify the clinical situation for PCa in Asia and use the outcomes for the purposes of international comparison. Following the first meeting in Tokyo in December 2015, the second A-CaP meeting was held in Seoul, Korea, in September 2016. This, the third A-CaP meeting, was held on October 14, 2017, in Chiang Mai, Thailand, with the participation of members and collaborators from 12 countries and regions. In the meeting, participating countries and regions presented the current status of data collection, and the A-CaP office presented a preliminary analysis of the registered cases received from each country and region. Participants discussed ongoing challenges relating to data input and collection, institutional, and legislative issues that may present barriers to data sharing, and the outlook for further patient registrations through to the end of the registration period in December 2018. In addition to A-CaP-specific discussions, a series of special lectures were also delivered on the situation for health insurance in the United States, the correlation between insurance coverage and PCa outcomes, and the outlook for robotic surgery in the Asia-Pacific region. Members also confirmed the principles of authorship in collaborative studies, with a view to publishing original articles based on A-CaP data in the future.

Physician Perception of Grade Group 1 Prostate Cancer

BACKGROUND

Despite its low-risk nature, grade group 1 (GG 1) prostate cancer (PCa) remains overtreated. This suggests a disconnect between daily physician practice and the standard of care. We hypothesized that GG 1 disease is overtreated because of common misconceptions regarding its true natural history.

OBJECTIVE

To survey physicians worldwide to better understand their approach to management of GG 1 PCa.

DESIGN, SETTING, AND PARTICIPANTS

A 17-question survey was sent to urology, radiation oncology, and pathology societies on six continents, and was posted on Twitter. Responses were collected and analyzed.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Pearson's χ2 test was used to assess correlation between physician-related variables and the perception of active surveillance (AS) for GG 1 PCa. Logistic regression was used for multivariable analysis. Statistical analysis was performed using SPSS version 21.

RESULTS AND LIMITATIONS

Among 1303 participants, 55% were urologists, 47% had completed fellowship, and 49% practice in an academic setting. Among the clinicians, 724 (83%) routinely recommend AS for GG 1 PCa and have never/rarely regretted it, while 18 (2%) "often" regretted it. Routine AS was more common among physicians aged <40 yr, those in practice for <10 yr, and those living in North America, Europe, or Australia/New Zealand. More than one-third of the respondents practicing in nonacademic settings reported 15-yr PCa mortality in low-risk PCa of >3%. Regarding reclassification of GG 1 to a precancerous lesion, 428 (39%) felt that this is a good idea, 340 (31%) disagreed, and 323 (30%) were uncertain. Those in support were more likely to be aged <40 yr (p = 0.001), in practice for <5 yr (p = 0.005), urologists (p < 0.001), and fellows trained in urologic oncology (p < 0.001). Opposition was common among pathologists (61%). Among terminologies proposed to replace "cancer" for GG 1 are neoplasm of low malignant potential (51% approval), indolent neoplasm rarely requiring treatment (23%), and indolent lesion of epithelial origin (8%).

CONCLUSIONS

AS is more commonly recommended by physicians who are younger, are fellowship-trained in urologic oncology, practice in academic settings, and are based in North America, Europe, or Australia/New Zealand. Misconceptions regarding AS outcomes may hinder its adoption. Frequent use of AS is associated with support for changing the "cancer" nomenclature.

PATIENT SUMMARY

In this study, we found that active surveillance remains underused in the management of low-risk prostate cancer because of incorrect perceptions regarding cancer outcomes. Omitting the word "cancer" for low-risk lesions is a challenging but promising effort that is favored by many clinicians, particularly by those who advocate for active surveillance.

Radiotherapy after radical prostatectomy: Effect of timing of postprostatectomy radiation on functional outcomes

INTRODUCTION AND OBJECTIVE

The timing of radiotherapy (RT) after prostatectomy is controversial, and its effect on sexual, urinary, and bowel function is unknown. This study seeks to compare patient-reported functional outcomes after radical prostatectomy (RP) and postprostatectomy radiation as well as elucidate the timing of radiation to allow optimal recovery of function.

METHODS

The Comparative Effectiveness Analysis of Surgery and Radiation (CEASAR) study is a prospective, population-based, observational study of men with localized prostate cancer. Patient-reported sexual, urinary, and bowel functional outcomes were measured using the 26-item Expanded Prostate Index Composite at baseline and at 6, 12, 36, and 60 months after enrollment. Functional outcomes were compared among men undergoing RP alone, post-RP adjuvant radiation (RP + aRT), and post-RP salvage radiation (RP + sRT) using multivariable models controlling for baseline clinical, demographic, and functional characteristics.

RESULTS

Among 1,482 CEASAR participants initially treated with RP for clinically localized prostate cancer, 11.5% (N = 170) received adjuvant (aRT, N = 57) or salvage (sRT, N = 113) radiation. Men who received post-RP RT had worse scores in all domains (sexual function [-9.0, 95% confidence interval {-14.5, -3.6}, P < 0.001], incontinence [-8.8, {-14.0, -3.6}, P < 0.001], irritative voiding [-5.9, {-9.0, -2.8}, P < 0.001], bowel irritative [-3.5, {-5.8, -1.2}, P = 0.002], and hormonal function [-4.5, {-7.2, -1.7}, P = 0.001]) compared to RP alone at 5 years of follow-up. Compared to men treated with RP alone in an adjusted linear model, sRT was associated with significantly worse scores in all functional domains. aRT was associated with significantly worse incontinence, urinary irritation, and hormonal function domain scores compared to RP alone at 5 years of follow-up. On multivariable modeling, RT administered approximately 24 months after RP was associated with the smallest decline in sexual domain score, with an adjusted mean decrease of 8.85 points (95% confidence interval [-19.8, 2.1]) from post-RP, pre-RT baseline.

CONCLUSIONS

In men with localized prostate cancer, post-RP RT was associated with significantly worse sexual, urinary, and bowel function domain scores at 5 years compared to RP alone. Radiation delayed for approximately 24 months after RP may be optimal for preserving erectile function compared to radiation administered closer to the time of RP.

Multicolor fluorescence microscopy for surgical guidance using a chip-scale imager with a low-NA fiber optic plate and a multi-bandpass interference filter

In curative-intent cancer surgery, intraoperative fluorescence imaging of both diseased and healthy tissue can help to ensure successful removal of all gross and microscopic disease with minimal damage to neighboring critical structures, such as nerves. Current fluorescence-guided surgery (FGS) systems, however, rely on bulky and rigid optics that incur performance-limiting trade-offs between sensitivity and maneuverability. Moreover, many FGS systems are incapable of multiplexed imaging. As a result, clinical FGS is currently limited to millimeter-scale detection of a single fluorescent target. Here we present a scalable, lens-less fluorescence imaging chip, VISION, capable of sensitive and multiplexed detection within a compact form factor. Central to VISION is a novel optical frontend design combining a low-numerical-aperture fiber optic plate (LNA-FOP) and a multi-bandpass interference filter, which is affixed to a custom CMOS image sensor. The LNA-FOP acts as a planar collimator to improve resolution and compensate for the angle-sensitivity of the interference filter, enabling high-resolution and multiplexed fluorescence imaging without lenses. We show VISION is capable of detecting tumor foci of less than 100 cells at near video framerates and, as proof of principle, can simultaneously visualize both tumor and nerves in ex vivo prostate tissue.