Interim Results from the IMPACT Study: Evidence for Prostate-specific Antigen Screening in BRCA2 Mutation Carriers

Clinical performance of magnetic resonance imaging and biomarkers for prostate cancer diagnosis in men at high genetic risk

OBJECTIVES

To evaluate different scenarios for the management of early diagnosis of cancer (PCa) in men at high genetic risk, using recently developed blood and urinary molecular biomarkers in combination with clinical information alongside multiparametric magnetic resonance imaging (mpMRI).

PATIENTS AND METHODS

A total of 322 patients with a high genetic risk (familial or personal history of cancers or a predisposing germline variant) were included in this study. The primary outcome was the detection rates of PCa (positive biopsy) or clinically significant PCa (biopsy with International Society of Urological Pathology [ISUP] grade >1). Clinical parameters included age, body mass index, ancestry, and germline mutational status, mpMRI, prostate-specific antigen density (PSAD), Prostate Health Index and urinary markers (Prostate Cancer Associated 3, SelectMdx™ and T2:ERG score) were assessed. Sensitivity (Se) and specificity (Sp) for each marker at their recommended cut-off for clinical practice were calculated. Comparison between diagnoses accuracy of each procedure and scenario was computed using mutual information based and direct effect contribution using a supervised Bayesian network approach.

RESULTS

A mpMRI Prostate Imaging-Reporting and Data System (PI-RADS) score ≥3 showed higher Se than mpMRI PI-RADS score ≥4 for detection of PCa (82% vs 61%) and for the detection of ISUP grade >1 lesions (96% vs 80%). mpMRI PI-RADS score ≥3 performed better than a PSA level of ≥3 ng/mL (Se 96%, Sp 53% vs Se 91%, Sp 8%) for detection of clinically significant PCa. In case of negative mpMRI results, the supervised Bayesian network approach showed that urinary markers (with the same accuracy for all) and PSAD of ≥0.10 ng/mL/mL were the most useful indicators of decision to biopsy.

CONCLUSIONS

We found that screening men at high genetic risk of PCa must be based on mpMRI without pre-screening based on a PSA level of >3 ng/mL, to avoid missing too many ISUP grade >1 tumours and to significantly reduce the number of unnecessary biopsies. However, urinary markers or a PSAD of ≥0.10 ng/mL/mL when mpMRI was negative increased the detection of ISUP grade >1 cancers. We suggest that a baseline mpMRI be discussed for men at high genetic risk from the age of 40 years.

The roles of proteases in prostate cancer

Since the proposition of the pro-invasive activity of proteolytic enzymes over 70 years ago, several roles for proteases in cancer progression have been established. About half of the 473 active human proteases are expressed in the prostate and many of the most well-characterized members of this enzyme family are regulated by androgens, hormones essential for development of prostate cancer. Most notably, several kallikrein-related peptidases, including KLK3 (prostate-specific antigen, PSA), the most well-known prostate cancer marker, and type II transmembrane serine proteases, such as TMPRSS2 and matriptase, have been extensively studied and found to promote prostate cancer progression. Recent findings also suggest a critical role for proteases in the development of advanced and aggressive castration-resistant prostate cancer (CRPC). Perhaps the most intriguing evidence for this role comes from studies showing that the protease-activated transmembrane proteins, Notch and CDCP1, are associated with the development of CRPC. Here, we review the roles of proteases in prostate cancer, with a special focus on their regulation by androgens.

The most efficient and effective BRCA1/2 testing strategy in epithelial ovarian cancer: Tumor-First or Germline-First?

OBJECTIVE

Genetic testing in epithelial ovarian cancer (OC) is essential to identify a hereditary cause like a germline BRCA1/2 pathogenic variant (PV). An efficient strategy for genetic testing in OC is highly desired. We evaluated costs and effects of two strategies; (i) Tumor-First strategy, using a tumor DNA test as prescreen to germline testing, and (ii) Germline-First strategy, referring all patients to the clinical geneticist for germline testing.

METHODS

Tumor-First and Germline-First were compared in two scenarios; using real-world uptake of testing and setting implementation to 100%. Decision analytic models were built to analyze genetic testing costs (including counseling) per OC patient and per family as well as BRCA1/2 detection probabilities. With a Markov model, the life years gained among female relatives with a germline BRCA1/2 PV was investigated.

RESULTS

Focusing on real-world uptake, with the Tumor-First strategy more OC patients and relatives with a germline BRCA1/2 PV are detected (70% versus 49%), at lower genetic testing costs (€1898 versus €2502 per patient, and €2511 versus €2930 per family). Thereby, female relatives with a germline BRCA1/2 PV can live on average 0.54 life years longer with Tumor-First compared to Germline-First. Focusing on 100% uptake, the genetic testing costs per OC patient are substantially lower in the Tumor-First strategy (€2257 versus €4986).

CONCLUSIONS

The Tumor-First strategy in OC patients is more effective in identifying germline BRCA1/2 PV at lower genetic testing costs per patient and per family. Optimal implementation of Tumor-First can further improve detection of heredity in OC patients.

Roles of the PARP Inhibitor in BRCA1 and BRCA2 Pathogenic Mutated Metastatic Prostate Cancer: Direct Functions and Modification of the Tumor Microenvironment

Cancer cells frequently exhibit defects in DNA damage repair (DDR), leading to genomic instability. Mutations in DDR genes or epigenetic alterations leading to the downregulation of DDR genes can result in increased dependency on other DDR pathways. Therefore, DDR pathways could be a treatment target for various cancers. In fact, polyadenosine diphosphatase ribose polymerase (PARP) inhibitors, such as olaparib (Lynparza®), have shown remarkable therapeutic efficacy against BRCA1/2-mutant cancers through synthetic lethality. Recent genomic analytical advancements have revealed that BRCA1/BRCA2 pathogenic variants are the most frequent mutations among DDR genes in prostate cancer. Currently, the PROfound randomized controlled trial is investigating the efficacy of a PARP inhibitor, olaparib (Lynparza®), in patients with metastatic castration-resistant prostate cancer (mCRPC). The efficacy of the drug is promising, especially in patients with BRCA1/BRCA2 pathogenic variants, even if they are in the advanced stage of the disease. However, olaparib (Lynparza®) is not effective in all BRCA1/2 mutant prostate cancer patients and inactivation of DDR genes elicits genomic instability, leading to alterations in multiple genes, which eventually leads to drug resistance. In this review, we summarize PARP inhibitors' basic and clinical mechanisms of action against prostate cancer cells and discuss their effects on the tumor microenvironment.

Genetic and Genomic Testing for Prostate Cancer: Beyond DNA Repair

Significant progress has been made in genetic and genomic testing for prostate cancer across the disease spectrum. Molecular profiling is increasingly relevant for routine clinical management, fueled in part by advancements in testing technology and integration of biomarkers into clinical trials. In metastatic prostate cancer, defects in DNA damage response genes are now established predictors of benefit to US Food and Drug Administration-approved poly (ADP-ribose) polymerase inhibitors and immune checkpoint inhibitors, and trials are actively investigating these and other targeted treatment strategies in earlier disease states. Excitingly, opportunities for molecularly informed management beyond DNA damage response genes are also maturing. Germline genetic variants (eg, BRCA2 or MSH2/6) and polygenic germline risk scores are being investigated to inform cancer screening and active surveillance in at-risk carriers. RNA expression tests have recently gained traction in localized prostate cancer, enabling patient risk stratification and tailored treatment intensification via radiotherapy and/or androgen deprivation therapy for localized or salvage treatment. Finally, emerging minimally invasive circulating tumor DNA technology promises to enhance biomarker testing in advanced disease pending additional methodological and clinical validation. Collectively, genetic and genomic tests are rapidly becoming indispensable tools for informing the optimal clinical management of prostate cancer.

Serum testosterone and prostate cancer in men with germline BRCA1/2 pathogenic variants

Objectives

The relation of serum androgens and the development of prostate cancer (PCa) is subject of debate. Lower total testosterone (TT) levels have been associated with increased PCa detection and worse pathological features after treatment. However, data from the Reduction by Dutasteride of Prostate Cancer Events (REDUCE) and Prostate Cancer Prevention (PCPT) trial groups indicate no association. The aim of this study is to investigate the association of serum androgen levels and PCa detection in a prospective screening study of men at higher genetic risk of aggressive PCa due to BRCA1/2 pathogenic variants (PVs), the IMPACT study.

Methods

Men enrolled in the IMPACT study provided serum samples during regular visits. Hormonal levels were calculated using immunoassays. Free testosterone (FT) was calculated from TT and sex hormone binding globulin (SHBG) using the Sodergard mass equation. Age, body mass index (BMI), prostate-specific antigen (PSA) and hormonal concentrations were compared between genetic cohorts. We also explored associations between age and TT, SHBG, FT and PCa, in the whole subset and stratified by BRCA1/2 PVs status.

Results

A total of 777 participants in the IMPACT study had TT and SHBG measurements in serum samples at annual visits, giving 3940 prospective androgen levels, from 266 BRCA1 PVs carriers, 313 BRCA2 PVs carriers and 198 non-carriers. The median number of visits per patient was 5. There was no difference in TT, SHBG and FT between carriers and non-carriers. In a univariate analysis, androgen levels were not associated with PCa. In the analysis stratified by carrier status, no significant association was found between hormonal levels and PCa in non-carriers, BRCA1 or BRCA2 PVs carriers.

Conclusions

Male BRCA1/2 PVs carriers have a similar androgen profile to non-carriers. Hormonal levels were not associated with PCa in men with and without BRCA1/2 PVs. Mechanisms related to the particularly aggressive phenotype of PCa in BRCA2 PVs carriers may therefore not be linked with circulating hormonal levels.

Screening for prostate cancer: evidence, ongoing trials, policies and knowledge gaps

Long-term screening with serum prostate-specific antigen (PSA) and systematic prostate biopsies can reduce prostate cancer mortality but leads to unacceptable overdiagnosis. Over the past decade, diagnostic methods have improved and the indolent nature of low-grade prostate cancer has been established. These advances now enable more selective detection of potentially lethal prostate cancer. This non-systematic review summarises relevant diagnostic advances, previous and ongoing screening trials, healthcare policies and important remaining knowledge gaps. Evidence synthesis and conclusions: The strong association between low serum PSA values and minimal long-term risk of prostate cancer death allows for adjusting screening intervals. Use of risk calculators, biomarkers and MRI to select men with a raised PSA value for biopsy and lesion-targeting rather than systematic prostate biopsies reduce the detection of low-grade cancer and thereby overdiagnosis. These improvements recently led the European Union to recommend its member states to evaluate the feasibility and effectiveness of organised screening programmes for prostate cancer. Nonetheless, important knowledge gaps remain such as the performance of modern diagnostic methods in long-term screening programmes and their impact on mortality. The knowledge gaps are currently being addressed in three large randomised screening trials. Population-based pilot programmes will contribute critical practical experience.

Positive family history as a predictor for disease outcomes after radical prostatectomy for nonmetastatic prostate cancer

Background

While family history (FHx) of prostate cancer (PCa) increases the risk of PCa, comparably less is known regarding the impact of FHx on pathologic and oncologic outcomes after radical prostatectomy (RP).

Methods

We retrospectively reviewed our multicenter database comprising 6,041 nonmetastatic PCa patients treated with RP. Patients with a FHx of PCa in one or more first-degree relatives were considered as FHx positive. We examined the association of FHx with pathologic outcomes and biochemical recurrence (BCR) using logistic and Cox regression models, respectively.

Results

In total, 1,677 (28%) patients reported a FHx of PCa. Compared to patients without FHx, those with, were younger at RP (median age of 59 vs. 62 years, p < 0.01), and had significantlymore favorable biopsy and RP histopathologic findings. On multivariable logistic regression analysis, positive FHx was associated with extracapsular extension (odds ratio [OR] 0.77, 95% confidence interval [CI] 0.66-0.90, p < 0.01; model AUC 0.73) and upgrading (OR 0.70, 95% CI 0.62-0.80, p < 0.01; model AUC 0.68). Incorporating FHx significantly improved the AUC of the base model for upgrading (p < 0.01). Positive FHx was not associated with BCR in pre- and postoperative multivariable models (p = 0.1 and p = 0.7); c-indexes of Cox multivariable models were: 0.73 and 0.82, respectively.

Conclusions

We found that patients with clinically nonmetastatic PCa who have positive FHx of PCa undergo RP at a younger age and have more favorable pathologic outcomes. Nevertheless, FHx of PCa did not confer better BCR rates, suggesting that FHx leads to potentially early detection and treatment without impact on BCR.

Matching BRCA and prostate cancer in a public health system: Report of the Italian Society for Uro-Oncology (SIUrO) consensus project

The recent approval of PARP inhibitors for the treatment of metastatic -castration-resistant prostate cancer (mCRPC) patients with BRCA mutations firstly introduced the possibility of proposing a targeted treatment in this disease. However, the availability of this therapeutic option raises a number of questions concerning the management of prostate cancer in everyday clinical practice: the timing and method of detecting BRCA mutations, the therapeutic implications of the detection, and the screening of the members of the family of a prostate cancer patient with a BRCA alteration. These challenging issues led the Italian Society for Uro-Oncology (SIUrO) to organise a Consensus Conference aimed to develop suggestions capable of supporting clinicians managing prostate cancer patients. The present paper described the development of the statements discussed during the consensus, which involved all of the most important Italian scientific societies engaged in the multi-disciplinary and multi-professional management of the disease.

Genetic Risk Prediction for Prostate Cancer: Implications for Early Detection and Prevention

CONTEXT

Prostate cancer (PCa) is a leading cause of death and partially heritable. Genetic risk prediction might be useful for strategies to reduce PCa mortality through early detection and prevention.

OBJECTIVE

To review evidence for genetic risk prediction for PCa.

EVIDENCE ACQUISITION

A collaborative literature review was conducted using PubMed and Google Scholar. Search terms included genetic, risk, prediction, and "prostate cancer". Articles addressing screening, early detection, or prevention were prioritized, as were studies involving diverse populations.

EVIDENCE SYNTHESIS

Rare pathogenic mutations (RPMs), especially in DNA damage repair genes, increase PCa risk. RPMs in BRCA2 are most clearly deleterious, conferring 2-8.6 times higher risk of PCa and a higher risk of aggressive disease. Common genetic variants can be combined into genetic risk scores (GRSs). A high GRS (top 20-25% of the population) confers two to three times higher risk of PCa than average; a very high GRS (top 1-5%) confers six to eight times higher risk. GRSs are not specific for aggressive PCa, possibly due to methodological limitations and/or a field effect of an elevated risk for both low- and high-grade PCa. It is challenging to disentangle genetics from structural racism and social determinants of health to understand PCa racial disparities. GRSs are independently associated with a lethal PCa risk after accounting for family history and race/ancestry. Healthy lifestyle might partially mitigate the risk of lethal PCa.

CONCLUSIONS

Genetic risk assessment is becoming more common; implementation studies are needed to understand the implications and to avoid exacerbating healthcare disparities. Men with a high genetic risk of PCa can reasonably be encouraged to adhere to a healthy lifestyle.

PATIENT SUMMARY

Prostate cancer risk is inherited through rare mutations and through the combination of hundreds of common genetic markers. Some men with a high genetic risk (especially BRCA2 mutations) likely benefit from early screening for prostate cancer. The risk of lethal prostate cancer can be reduced through a healthy lifestyle.

Genetic Aspects and Molecular Testing in Prostate Cancer: A Report from a Dutch Multidisciplinary Consensus Meeting

Background

Germline and tumour genetic testing in prostate cancer (PCa) is becoming more broadly accepted, but testing indications and clinical consequences for carriers in each disease stage are not yet well defined.

Objective

To determine the consensus of a Dutch multidisciplinary expert panel on the indication and application of germline and tumour genetic testing in PCa.

Design setting and participants

The panel consisted of 39 specialists involved in PCa management. We used a modified Delphi method consisting of two voting rounds and a virtual consensus meeting.

Outcome measurements and statistical analysis

Consensus was reached if ≥75% of the panellists chose the same option. Appropriateness was assessed by the RAND/UCLA appropriateness method.

Results and limitations

Of the multiple-choice questions, 44% reached consensus. For men without PCa having a relevant family history (familial PCa/BRCA-related hereditary cancer), follow-up by prostate-specific antigen was considered appropriate. For patients with low-risk localised PCa and a family history of PCa, active surveillance was considered appropriate, except in case of the patient being a BRCA2 germline pathogenic variant carrier. Germline and tumour genetic testing should not be done for nonmetastatic hormone-sensitive PCa in the absence of a relevant family history of cancer. Tumour genetic testing was deemed most appropriate for the identification of actionable variants, with uncertainty for germline testing. For tumour genetic testing in metastatic castration-resistant PCa, consensus was not reached for the timing and panel composition. The principal limitations are as follows: (1) a number of topics discussed lack scientific evidence, and therefore the recommendations are partly opinion based, and (2) there was a small number of experts per discipline.

Conclusions

The outcomes of this Dutch consensus meeting may provide further guidance on genetic counselling and molecular testing related to PCa.

Patient summary

A group of Dutch specialists discussed the use of germline and tumour genetic testing in prostate cancer (PCa) patients, indication of these tests (which patients and when), and impact of these tests on the management and treatment of PCa.

CanRisk-Prostate: A Comprehensive, Externally Validated Risk Model for the Prediction of Future Prostate Cancer

PURPOSE

Prostate cancer (PCa) is highly heritable. No validated PCa risk model currently exists. We therefore sought to develop a genetic risk model that can provide personalized predicted PCa risks on the basis of known moderate- to high-risk pathogenic variants, low-risk common genetic variants, and explicit cancer family history, and to externally validate the model in an independent prospective cohort.

MATERIALS AND METHODS

We developed a risk model using a kin-cohort comprising individuals from 16,633 PCa families ascertained in the United Kingdom from 1993 to 2017 from the UK Genetic Prostate Cancer Study, and complex segregation analysis adjusting for ascertainment. The model was externally validated in 170,850 unaffected men (7,624 incident PCas) recruited from 2006 to 2010 to the independent UK Biobank prospective cohort study.

RESULTS

The most parsimonious model included the effects of pathogenic variants in BRCA2, HOXB13, and BRCA1, and a polygenic score on the basis of 268 common low-risk variants. Residual familial risk was modeled by a hypothetical recessively inherited variant and a polygenic component whose standard deviation decreased log-linearly with age. The model predicted familial risks that were consistent with those reported in previous observational studies. In the validation cohort, the model discriminated well between unaffected men and men with incident PCas within 5 years (C-index, 0.790; 95% CI, 0.783 to 0.797) and 10 years (C-index, 0.772; 95% CI, 0.768 to 0.777). The 50% of men with highest predicted risks captured 86.3% of PCa cases within 10 years.

CONCLUSION

To our knowledge, this is the first validated risk model offering personalized PCa risks. The model will assist in counseling men concerned about their risk and can facilitate future risk-stratified population screening approaches.

Initial outcomes and insights from a novel high-risk prostate cancer screening clinic

INTRODUCTION

Guidelines for germline testing in patients with prostate cancer (PCa) are identifying family members who require additional surveillance given pathogenic variants (PVs) that confer increased PCa risk. We established an interdisciplinary clinic for cancer surveillance in high-risk individuals aimed to implement screening recommendations. This study aimed to characterize the clinical features of this cohort.

PATIENTS AND METHODS

The Prostate Cancer Risk Clinic (PCRC) was established for unaffected individuals with germline PVs or a strong PCa family history. PCa screening, urine labs, and questionnaires were included in the visit. Individuals with BRCA1/2 PVs underwent clinical breast exam as well. Data from the initial visit were abstracted from the medical record and questionnaires for analysis.

RESULTS

Thirty-five individuals with increased PCa risk were followed by the PCRC with a median age of 47 years of age. Twenty individuals (57%) had a family history of PCa, and 34 (97%) had a germline PV associated with an increased risk for developing PCa. Four individuals underwent biopsy due to care in the PCRC, with one PCa identified in an individual with TP53 PV. Median patient response scores indicated mild symptoms of an enlarged prostate (AUASS), normal erectile function (SHIM), and relatively low anxiety about developing PCa (MAX-PC). However, there were notable "outlier" scores on each questionnaire.

CONCLUSIONS

Individuals with prostates and BRCA1/2 PVs, among other germline PVs, can benefit from a comprehensive interdisciplinary approach to high-risk management. PCa was identified in an individual with a non-BRCA PV, emphasizing the importance and need for high-risk screening guidelines across all genes with increased risk for PCa. "Outlier" patient response scores demonstrate that some participants experienced worse symptoms or anxiety than was indicated by median scores alone.

Prostate cancer risk, screening and management in patients with germline BRCA1/2 mutations

Mutations in the BRCA1 and BRCA2 tumour suppressor genes are associated with prostate cancer risk; however, optimal screening protocols for individuals with these mutations have been a subject of debate. Several prospective studies of prostate cancer incidence and screening among BRCA1/2 mutation carriers have indicated at least a twofold to fourfold increase in prostate cancer risk among carriers of BRCA2 mutations compared with the general population. Moreover, BRCA2 mutations are associated with more aggressive, high-grade disease characteristics at diagnosis, more aggressive clinical behaviour and greater prostate cancer-specific mortality. The risk for BRCA1 mutations seems to be attenuated compared with BRCA2. Prostate-specific antigen (PSA) measurement or prostate magnetic resonance imaging (MRI) alone is an imperfect indicator of clinically significant prostate cancer; therefore, BRCA1/2 mutation carriers might benefit from refined risk stratification strategies. However, the long-term impact of prostate cancer screening is unknown, and the optimal management of BRCA1/2 carriers with prostate cancer has not been defined. Whether timely localized therapy can improve overall survival in the screened population is uncertain. Long-term results of prospective studies are awaited to confirm the optimal screening strategies and benefits of prostate cancer screening among BRCA1/2 mutation carriers, and whether these approaches ultimately have a positive impact on survival and quality of life in these patients.

How the Analysis of the Pathogenetic Variants of DDR Genes Will Change the Management of Prostate Cancer Patients

Herein, we analyze answers achieved, open questions, and future perspectives regarding the analysis of the pathogenetic variants (PV) of DNA damage response (and repair) (DDR) genes in prostate cancer (PC) patients. The incidence of PVs in homologous recombination repair (HRR) genes among men with metastatic PC varied between 11% and 33%, which was significantly higher than that in non-metastatic PC, and BRCA2 mutations were more frequent when compared to other DDR genes. The determination of the somatic or germline PVs of BRCA2 was able to define a tailored therapy using PARP inhibitors in metastatic castration-resistant prostate cancer (mCRPC) progression after first-line therapy, with significant improvements in the radiologic progression-free survival (rPFS) and overall survival (OS) rates. We propose testing all metastatic PC patients for somatic and germline HRR mutations. Somatic determination on the primary site or on historic paraffin preparations with a temporal distance of no longer than 5 years should be preferred over metastatic site biopsies. The prognostic use of DDR PVs will also be used in selected high-risk cases with non-metastatic stages to better arrange controls and therapeutic primary options. We anticipate that the use of poly-ADP-ribose polymerase (PARP) inhibitors in hormone-sensitive prostate cancer (HSPC) and in combination with androgen receptor signaling inhibitors (ARSI) will be new strategies.

Mainstream germline genetic testing in men with metastatic prostate cancer: design and protocol for a multicenter observational study

BACKGROUND

In international guidelines, germline genetic testing is recommended for patients with metastatic prostate cancer. Before undergoing germline genetic testing, these patients should receive pre-test counseling. In the standard genetic care pathway, pre-test counseling is provided by a healthcare professional of a genetics department. Because the number of patients with metastatic prostate cancer is large, the capacity in the genetics departments might be insufficient. Therefore, we aim to implement so-called mainstream genetic testing in the Netherlands for patients with metastatic prostate cancer. In a mainstream genetic testing pathway, non-genetic healthcare professionals discuss and order germline genetic testing. In our DISCOVER study, we will assess the experiences among patients and non-genetic healthcare professionals with this new pathway.

METHODS

A multicenter prospective observational cohort study will be conducted in 15 hospitals, in different regions of the Netherlands. We developed an online training module on genetics in prostate cancer and the counseling of patients. After completion of this module, non-genetic healthcare professionals will provide pre-test counseling and order germline genetic testing in metastatic prostate cancer patients. Both non-genetic healthcare professionals and patients receive three questionnaires. We will determine the experience with mainstream genetic testing, based on satisfaction and acceptability. Patients with a pathogenic germline variant will also be interviewed. We will determine the efficacy of the mainstreaming pathway, based on time investment for non-genetic healthcare professionals and the prevalence of pathogenic germline variants.

DISCUSSION

This study is intended to be one of the largest studies on mainstream genetic testing in prostate cancer. The results of this study can improve the mainstream genetic testing pathway in patients with prostate cancer.

TRIAL REGISTRATION

The study is registered in the WHO's International Clinical Trials Registry Platform (ICTRP) under number NL9617.

Characteristics of BRCA2 Mutated Prostate Cancer at Presentation

Genetic alterations of DNA repair genes, particularly BRCA2 in patients with prostate cancer, are associated with aggressive behavior of the disease. It has reached consensus that somatic and germline tests are necessary when treating advanced prostate cancer patients. Yet, it is unclear whether the mutations are associated with any presenting clinical features. We assessed the incidences and characteristics of BRCA2 mutated cancers by targeted sequencing in 126 sets of advanced prostate cancer tissue sequencing data. At the time of diagnosis, cT3/4, N1 and M1 stages were 107 (85%), 54 (43%) and 35 (28%) samples, respectively. BRCA2 alterations of clinical significance by AMP/ASCO/CAP criteria were found in 19 of 126 samples (15.1%). The BRCA2 mutated cancer did not differ in the distributions of TNM stage, Gleason grade group or histological subtype compared to BRCA2 wild-type cancers. Yet, they had higher tumor mutation burden, and higher frequency of ATM and BRCA1 mutations (44% vs. 10%, p = 0.002 and 21% vs. 4%, p = 0.018, respectively). Of the metastatic subgroup (M1, n = 34), mean PSA was significantly lower in BRCA2 mutated cancers than wild-type (p = 0.018). In the non-metastatic subgroup (M0, n = 64), PSA was not significantly different (p = 0.425). A similar trend was noted in multiple metastatic prostate cancer public datasets. We conclude that BRCA2 mutated metastatic prostate cancers may present in an advanced stage with relatively low PSA.

Successful case of olaparib treatment for castration-resistant prostate cancer with multiple DNA repair gene mutations: Use of comprehensive genome profiling for treatment-refractory cases

Herein, we report a case of a 59-year-old man with advanced castration-resistant prostate cancer with rectal invasion. Multimodal treatment, including drug therapy, surgery, and radiation therapy was sequentially performed; however, lymph node metastases repeatedly occurred. Tumor genomic profiling using FoundationOne CDx identified pathogenic alterations in three DNA repair genes, including BRCA2 frameshift mutation. Olaparib, a poly-ADP ribose polymerase inhibitor, showed marked response. Castration-resistant prostate cancer with multiple DNA repair genes was successfully treated with olaparib; comprehensive genome profiling can lead to its optimal clinical management.

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Castration-resistant prostate cancer was successfully treated with olaparib.

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The prostate cancer had pathogenic alterations in three DNA repair genes.

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Genome profiling can lead to optimal clinical management in prostate cancer.

Controversies and Open Questions in Management of Cancer-Free Carriers of Germline Pathogenic Variants in BRCA1/BRCA2

Females harboring germline BRCA1/BRCA2 (BRCA) P/LPV are offered a tight surveillance scheme from the age of 25−30 years, aimed at early detection of specific cancer types, in addition to risk-reducing strategies. Multiple national and international surveillance guidelines have been published and updated over the last two decades from geographically diverse countries. We searched for guidelines published between 1 January 2015 and 1 May 2022. Differences between guidelines on issues such as primary prevention, mammography screening in young (<30 years) carriers, MRI screening in carriers above age 65 years, breast imaging (if any) after risk-reducing bilateral mastectomy, during pregnancy, and breastfeeding, and hormone-replacement therapy, are just a few notable examples. Beyond formal guidelines, BRCA carriers’ concerns also focus on the timing of risk-reducing surgeries, fertility preservation, management of menopausal symptoms in cancer survivors, and pancreatic cancer surveillance, issues that, for some, there are no data to support evidence-based recommendations. This review discusses these unsettled issues, emphasizing the importance of future studies to enable global guideline harmonization for optimal surveillance strategies. Moreover, it raises the unmet need for personalized risk stratification and surveillance in BRCA P/LPV carriers.

BRCA Mutations in Ovarian and Prostate Cancer: Bench to Bedside

Simple Summary

DNA damage is one of the hallmarks of cancer. Epithelial ovarian cancer (EOC) —especially the high-grade serous subtype—harbors a defect in at least one DNA damage response (DDR) pathway. Defective DDR results from a variety of lesions affecting homologous recombination (HR) and nonhomologous end joining (NHEJ) for double strand breaks, base excision repair (BER), and nucleotide excision repair (NER) for single strand breaks and mismatch repair (MMR). Apart from the EOC, mutations in the DDR genes, such as BRCA1 and BRCA2, are common in prostate cancer as well. Among them, BRCA2 lesions are found in 12% of metastatic castration-resistant prostate cancers, but very rarely in primary prostate cancer. Better understanding of the DDR pathways is essential in order to optimize the therapeutic choices, and has led to the design of biomarker-driven clinical trials. Poly(ADP-ribose) polymerase (PARP) inhibitors are now a standard therapy for EOC patients, and more recently have been approved for the metastatic castration-resistant prostate cancer with alterations in DDR genes. They are particularly effective in tumours with HR deficiency.

Abstract

DNA damage repair (DDR) defects are common in different cancer types, and these alterations can be exploited therapeutically. Epithelial ovarian cancer (EOC) is among the tumours with the highest percentage of hereditary cases. BRCA1 and BRCA2 predisposing pathogenic variants (PVs) were the first to be associated with EOC, whereas additional genes comprising the homologous recombination (HR) pathway have been discovered with DNA sequencing technologies. The incidence of DDR alterations among patients with metastatic prostate cancer is much higher compared to those with localized disease. Genetic testing is playing an increasingly important role in the treatment of patients with ovarian and prostate cancer. The development of poly (ADP-ribose) polymerase (PARP) inhibitors offers a therapeutic strategy for patients with EOC. One of the mechanisms of PARP inhibitors exploits the concept of synthetic lethality. Tumours with BRCA1 or BRCA2 mutations are highly sensitive to PARP inhibitors. Moreover, the synthetic lethal interaction may be exploited beyond germline BRCA mutations in the context of HR deficiency, and this is an area of ongoing research. PARP inhibitors are in advanced stages of development as a treatment for metastatic castration-resistant prostate cancer. However, there is a major concern regarding the need to identify reliable biomarkers predictive of treatment response. In this review, we explore the mechanisms of DDR, the potential for genomic analysis of ovarian and prostate cancer, and therapeutics of PARP inhibitors, along with predictive biomarkers.

Germline genetics of prostate cancer

BACKGROUND

An important fraction (>/~10%) of men with high-risk, localized prostate cancer and metastatic prostate cancer carry germline (heritable) pathogenic and likely pathogenic variants (also known as mutations) in DNA repair genes. These can represent known or suspected autosomal dominant cancer predisposition syndromes. Growing evidence suggests that pathogenic variants in key genes involved in homologous recombination and mismatch DNA repair are important in prostate cancer initiation and/or the development of metastases.

AIMS

Here we provide a comprehensive review regarding individual genes and available literature regarding risks for developing prostate cancer, and discuss current national guidelines for germline genetic testing in the prostate cancer population and treatment implications.

RESULTS

The association with prostate cancer risk and treatment implications is best understood for those with germline mutations of BRCA2, with emerging data supporting associations with ATM, CHEK2, BRCA1, HOXB13, MSH2, MSH6, PALB2, TP53 and NBN. Treatment implications in the metastatic castration resistant prostate cancer setting include rucaparib and olaparib, and pembrolizumab with potential clinical trial opportunities in earlier disease settings.

DISCUSSION

The data summarized in this review has led to the expansion of national guidelines for germline genetic testing in prostate cancer. We review these guidelines, and discuss the importance of cascade genetic testing of relatives, diverse populations with attention to inclusion, as well as prostate cancer screening updates and clinical trial opportunities for men who carry genetic risk factors for prostate cancer.

Clinical implications of homologous recombination repair mutations in prostate cancer

Prostate cancer is a disease with significant interpatient genomics, with a proportion of patients presenting mutations in key homologous recombination repair (HRR) gene aberrations, particularly in late-stage disease. A better understanding of the genomic landscape of prostate cancer and the prognostic and predictive value of HRR mutations could lead to more precise care for prostate cancer patients. BRCA1/2 mutations are associated with a more aggressive disease course and higher risk of developing lethal prostate cancer, but also identify patients who could benefit from directed therapeutic strategies with PARP inhibitors. Other HRR mutations are also frequent but their prognostic and predictive value for prostate cancer patients is less clear. Moreover, a proportion of these mutations are associated with inherited germline defects, being relevant for the patients' risk of second malignancies but also to inform their relatives' risk of cancer through cascade testing. In this manuscript, we review current knowledge of the prognostic and predictive value for different HHR alterations across the different prostate cancer disease states. Additionally, we assess the challenges to implement genomic testing in clinical practice for prostate cancer patients.

Association of Family History of Cancer with Clinical and Pathological Outcomes for Prostate Cancer Patients on Active Surveillance

PURPOSE

The impact of germline mutations associated with hereditary cancer syndromes in patients on active surveillance (AS) for prostate cancer is poorly defined. We examined the association between family history of prostate cancer (FHP) or family history of cancer (FHC) and risk of progression or adverse pathology at radical prostatectomy (RP) in patients on AS.

MATERIALS AND METHODS

Patients on AS at a single tertiary-care center between 2000-2019 were categorized by family history. Disease progression was defined as an increase in Gleason grade on biopsy. Adverse pathology was defined as upgrading/upstaging at RP. Multivariable Cox and logistic regression models were used to assess association between family history and time to progression or adverse pathology, respectively.

RESULTS

Among 3,211 evaluable patients, 669 (21%) had FHP, 34 (1%) had FHC and 95 (3%) had both; 753 progressed on AS and 481 underwent RP. FHP was associated with increased risk of progression (HR 1.31; 95% CI, 1.11-1.55; p=0.002) but FHC (HR 0.67; 95% CI, 0.30-1.50; p=0.3) or family history of both (HR 1.22; 95% CI, 0.81-1.85; p=0.3) were not. FHP, FHC or both were not associated with adverse pathology at RP (p >0.4).

CONCLUSIONS

While FHP was associated with an increased risk of progression on AS, wide confidence intervals render this outcome of unclear clinical significance. FHC was not associated with risk of progression on AS. In the absence of known genetically defined hereditary cancer syndrome, we suggest FHP and/or FHC should not be used as a sole trigger to preclude patients from enrolling on AS.

The role of prophylactic prostatectomy as a primary prevention strategy in high-risk germline mutation carriers

PURPOSE OF REVIEW

Men with high-risk germline mutations are at significantly higher risk of developing and dying from prostate cancer. Current screening and treatment paradigms may lead to missed opportunities for cure. Herein we review the current literature on prevention, screening and treatment of these carriers and explore the potential role of prophylactic prostatectomy in primary prevention of prostate cancer mortality.

RECENT FINDINGS

Prostate-specific antigen (PSA)-based screening has demonstrated marginal benefits in prostate cancer (PCa) survival and uncertainty remains on its true benefit among high-risk carriers. Recent results indicate that PCa in BRCA 2 carriers occurs at a higher incidence, younger age and progresses more rapidly compared with noncarriers. An intensified screening protocol of MRI and PSA in young carriers demonstrated how using PSA values alone may be insufficient. Current evidence indicates that high-risk carriers have worse survival outcomes after undergoing radical treatment for screening detected disease when compared with noncarriers.

SUMMARY

Prophylactic prostatectomy within the context of a clinical trial is a reasonable primary prevention option for discussion with high-risk carriers, especially BRCA2 carriers during the shared decision-making process. Limitations exist in the current strategies of early PSA screening followed by radical treatment in this group.

Genetic Testing and Its Clinical Application in Prostate Cancer Management: Consensus Statements from the Hong Kong Urological Association and Hong Kong Society of Uro-Oncology

Background

In recent years, indications for genetic testing in prostate cancer (PC) have expanded from patients with a family history of prostate and/or related cancers to those with advanced castration-resistant disease, and even to early PC patients for determination of the appropriateness of active surveillance. The current consensus aims to provide guidance to urologists, oncologists and pathologists working with Asian PC patients on who and what to test for in selected populations.

Methods

A joint consensus panel from the Hong Kong Urological Association and Hong Kong Society of Uro-Oncology was convened over a series of 5 physical and virtual meetings. A background literature search on genetic testing in PC was performed in PubMed, ClinicalKey, EBSCOHost, Ovid and ProQuest, and three working subgroups were formed to review and present the relevant evidence. Meeting agendas adopted a modified Delphi approach to ensure that discussions proceed in a structured, iterative and balanced manner, which was followed by an anonymous voting on candidate statements. Of 5 available answer options, a consensus statement was accepted if ≥ 75% of the panelists chose “Accept Completely” (Option A) or “Accept with Some Reservation” (Option B).

Results

The consensus was structured into three parts: indications for testing, testing methods, and therapeutic implications. A list of 35 candidate statements were developed, of which 31 were accepted. The statements addressed questions on the application of PC genetic testing data and guidelines to Asian patients, including patient selection for germline testing, selection of gene panel and tissue sample, provision of genetic counseling, and use of novel systemic treatments in metastatic castration-resistant PC patients.

Conclusion

This consensus provides guidance to urologists, oncologists and pathologists working with Asian patients on indications for genetic testing, testing methods and technical considerations, and associated therapeutic implications.

Genetic testing in prostate cancer management: Considerations informing primary care

Inherited genetic mutations can significantly increase the risk for prostate cancer (PC), may be associated with aggressive disease and poorer outcomes, and can have hereditary cancer implications for men and their families. Germline genetic testing (hereditary cancer genetic testing) is now strongly recommended for patients with advanced/metastatic PC, particularly given the impact on targeted therapy selection or clinical trial options, with expanded National Comprehensive Cancer Network guidelines and endorsement from multiple professional societies. Furthermore, National Comprehensive Cancer Network guidelines recommend genetic testing for men with PC across the stage and risk spectrum and for unaffected men at high risk for PC based on family history to identify hereditary cancer risk. Primary care is a critical field in which providers evaluate men at an elevated risk for PC, men living with PC, and PC survivors for whom germline testing may be indicated. Therefore, there is a critical need to engage and educate primary care providers regarding the role of genetic testing and the impact of results on PC screening, treatment, and cascade testing for family members of affected men. This review highlights key aspects of genetic testing in PC, the role of clinicians, with a focus on primary care, the importance of obtaining a comprehensive family history, current germline testing guidelines, and the impact on precision PC care. With emerging evidence and guidelines, clinical pathways are needed to facilitate integrated genetic education, testing, and counseling services in appropriately selected patients. There is also a need for providers to understand the field of genetic counseling and how best to collaborate to enhance multidisciplinary patient care.

An appraisal of genetic testing for prostate cancer susceptibility

Most criteria for genetic testing for prostate cancer susceptibility require a prior diagnosis of prostate cancer, in particular cases with metastatic disease are selected. Advances in the field are expected to improve outcomes through tailored treatments for men with advanced prostate cancer with germline pathogenic variants, although these are not currently offered in the curative setting. A better understanding of the value of genetic testing for prostate cancer susceptibility in screening, for early detection and prevention is necessary. We review and summarize the literature describing germline pathogenic variants in genes associated with increased prostate cancer risk and aggressivity. Important questions include: what is our ability to screen for and prevent prostate cancer in a man with a germline pathogenic variant and how does knowledge of a germline pathogenic variant influence treatment of men with nonmetastatic disease, with hormone-resistant disease and with metastatic disease? The frequency of germline pathogenic variants in prostate cancer is well described, according to personal and family history of cancer and by stage and grade of disease. The role of these genes in aggressive prostate cancer is also discussed. It is timely to consider whether or not genetic testing should be offered to all men with prostate cancer. The goals of testing are to facilitate screening for early cancers in unaffected high-risk men and to prevent advanced disease in men with cancer.

The tumor mutational landscape of BRCA2-deficient primary and metastatic prostate cancer

Carriers of germline BRCA2 pathogenic sequence variants have elevated aggressive prostate cancer risk and are candidates for precision oncology treatments. We examined whether BRCA2-deficient (BRCA2d) prostate tumors have distinct genomic alterations compared with BRCA2-intact (BRCA2i) tumors. Among 2536 primary and 899 metastatic prostate tumors from the ICGC, GENIE, and TCGA databases, we identified 138 primary and 85 metastatic BRCA2d tumors. Total tumor mutation burden (TMB) was higher among primary BRCA2d tumors, although pathogenic TMB did not differ by tumor BRCA2 status. Pathogenic and total single nucleotide variant (SNV) frequencies at KMT2D were higher in BRCA2d primary tumors, as was the total SNV frequency at KMT2D in BRCA2d metastatic tumors. Homozygous deletions at NEK3, RB1, and APC were enriched in BRCA2d primary tumors, and RB1 deletions in metastatic BRCA2d tumors as well. TMPRSS2-ETV1 fusions were more common in BRCA2d tumors. These results identify somatic alterations that hallmark etiological and prognostic differences between BRCA2d and BRCA2i prostate tumors.

PARP Inhibitors: A New Horizon for Patients with Prostate Cancer

The introduction of PARP inhibitors (PARPi) in prostate cancer is a milestone and provides a pathway to hope in fighting this disease. It is the first time that drugs, based on the concept of synthetic lethality, have been approved for prostate cancer. In addition, it is also the first time that genetic mutation tests have been included in the therapeutic algorithm of this disease, representing a significant step forward for precision and personalized treatment of prostate cancer. The objectives of this review are: (1) understanding the mechanism of action of PARPi in monotherapy and combinations; (2) gaining insights on patient selection for PARPi; (3) exposing the pivotal studies that have allowed its approval, and; (4) offering an overview of the ongoing trials. Nevertheless, many unsolved questions remain, such as the number of patients who could potentially benefit from PARPi, whether to use PARPi in monotherapy or in combination, and when is the best time to use them in advanced or localized disease. To answer these and other questions, many clinical trials are underway. Some of them have recently demonstrated promising results that may favor the introduction of new combinations in metastatic castration-resistant prostate cancer.

Two-year profile of the records of patients referred to Adana city hospital urology clinic due to PSA high in primary care: a retrospective review

Objective: To retrospectively evaluate the two-year records of patients referred to Adana City Training and Research Hospital by family physicians because of high prostate specific antigen (PSA), and to reveal the profile and related outcomes for clinical practices of family physicians about prostate cancer screening. Material and Method: The files of 102 patients, who were referred to our clinic by their family physicians due to high PSA between April 2019 and May 2021, were retrospectively evaluated. Demographic data of patients, presence of additional disease, family history, control serum PSA value examined in family medicine centers and in our hospital at time of first admission, complete urinalysis (TIT), ultrasonography (USG) and multiparametric magnetic resonance (mpMR) findings, transrectal ultrasonographic biopsy (TRUS-BX) results and biopsy were noted. The treatments administered according to the results (radical prostatectomy, radiotherapy, hormone therapy, chemotherapy) were recorded. Results: The mean age of the patients was 52.8±8.9 years. The PSA value of the patients at time of admission was 8.0±3.8 ng/ml. The mean PSA values measured at the time of admission to primary care and at the time of admission to Adana clinic after referral were 8.0±3.8 ng/ml and 8.0±3.0 ng/ml, respectively. There was no statistically significant difference between these values (p=0.2). Among all the patients presenting with elevated PSA, 36 (35%) patients underwent TRUS Bx, had prostate cancer as a result of pathology and underwent radical prostatectomy, which was the most common definitive treatment method with statistical significance (p

Germline Variant Spectrum Among African American Men Undergoing Prostate Cancer Germline Testing: Need for Equity in Genetic Testing

PURPOSE

Guidelines for prostate cancer (PCA) germline testing (GT) have expanded, with impact on clinical management and hereditary cancer assessment. African American (AA) men have lower engagement in GT, with concern for widening disparities in genetically informed care. We evaluated the germline spectrum in a cohort of men with PCA enriched for AA men who underwent GT to inform tailored genetic evaluation strategies.

METHODS

Participants included AA and White men with PCA tested with a 14-gene PCA panel: ATM, BRCA1, BRCA2, CHEK2, EPCAM, HOXB13, MLH1, MSH2, MSH6, NBN, PALB2, PMS2, RAD51D, and TP53. Germline analysis was performed per standard clinical testing and variant classification protocols. Data were compared with Fisher's exact, chi-squared, or two sample t-tests, as appropriate. Multivariable analysis was conducted using Akaike's Information Criterion. The significance level was set a priori at .05.

RESULTS

The data set included 427 men all tested using the 14-gene PCA panel: AA (n = 237, 56%) and White (n = 190, 44%). Overall, the pathogenic/likely pathogenic (P/LP) variant rate was 8.2%, with AA men having lower rates of P/LP variants then White men (5.91% v 11.05%, respectively; P = .05). Borderline associations with P/LP variant status were observed by race (AA v White; odds ratio = 0.51; P = .07) and age (> 50 v ≤ 50 years; odds ratio = 0.48; P = .06). The P/LP spectrum was narrower in AA men (BRCA2, PALB2, ATM, and BRCA1) than White men (BRCA2, ATM, HOXB13, CHEK2, TP53, and NBN). A significant difference was noted in rates of variants of uncertain significance (VUSs) between AA men and White men overall (25.32% v 16.32%; P = .02) and for carrying multiple VUSs (5.1% v 0.53%, P = .008).

CONCLUSION

Germline evaluation in a cohort enriched for AA men highlights the narrower spectrum of germline contribution to PCA with significantly higher rates of multiple VUSs in DNA repair genes. These results underscore the imperative to engage AA men in GT, the need for larger panel testing in AA men, and the necessity to incorporate novel genomic technologies to clarify VUS to discern the germline contribution to PCA. Furthermore, tailored genetic counseling for AA men is important to ensure understanding of VUS and promote equitable genetics care delivery.

Hereditary cancer risk assessment and genetic testing in the community urology practice setting

OBJECTIVES

To evaluate the feasibility of integrating a hereditary cancer risk assessment (HCRA) process in the community urology practice setting for patients with prostate cancer (PCa).

METHODS

In this prospective intervention, an HCRA process was implemented across six different community urology clinics between May 2019 and April 2020. The intervention included a process integration during which the workflow at each site was refined, a post-integration period during which HCRA was conducted in all patients with PCa, and a follow-up period during which healthcare providers and patients reported their satisfaction with the HCRA and genetic testing process.

RESULTS

Among patients who completed a family history assessment during the post-integration period, 23.6% met guideline criteria for genetic testing. Of all patients seen at the clinic during the post-integration period, 8.7% completed genetic testing; this was a twofold increase over the period immediately preceding process integration (4.2%), and a sevenfold increase over the same period 1 year prior (1.2%). The majority of providers reported that the HCRA was as important as other regularly performed assessments (61.0%) and planned to continue using the process in their practice (68.3%). Most patients believed that the genetic test results were important for their future cancer care (84.7%) and had already shared their test results with at least one family member (63.2%).

CONCLUSIONS

This study demonstrated that implementing an HCRA process in the community urology practice setting was feasible, generally favored by providers and patients, and resulted in an increase in the number of patients with PCa who completed genetic testing.

Germline testing and genetic counselling in prostate cancer

Genetic testing for prostate cancer is rapidly growing and is increasingly being driven by precision medicine. Rates of germline pathogenic variants have been reported in up to 15% of men with prostate cancer, particularly in metastatic disease, and results of genetic testing could uncover options for precision therapy along with a spectrum of hereditary cancer-predisposition syndromes with unique clinical features that have complex management options. Thus, the pre-test discussion, whether delivered by genetic counsellors or by health-care professionals in hybrid models, involves information on hereditary cancer risk, extent of gene testing, purpose of testing, medical history and family history, potential types of results, additional cancer risks that might be uncovered, genetically based management and effect on families. Understanding precision medicine, personalized cancer risk management and syndrome-related cancer risk management is important in order to develop collaborative strategies with genetic counselling for optimal care of patients and their families.

In this Review, Russo and Giri describe and discuss germline testing criteria, genetic testing strategies, genetically informed screening, precision management, delivery of genetic counselling or alternative genetic services and special considerations for men with prostate cancer.

Germline (hereditary) genetic testing is rising in importance for treatment, screening and risk assessment of prostate cancer.

Multiple hereditary cancer syndromes might be associated with prostate cancer, might confer risk of other cancerous and non-cancerous conditions, and can have hereditary cancer implications for family members. The rates of these syndromes can vary based upon the attributed genetic mutations.

Multiple aspects of germline testing should be discussed in the pre-test setting for men to make an informed decision, including the purpose of genetic testing, the benefits and risks of testing, hereditary cancer risk, identification of additional cancer risks, familial implications and the state of genetic discrimination protections.

Genetic evaluation can be conducted by genetic counsellors or a hybrid model can be employed, in which health-care providers deliver pre-test informed consent for testing, order testing and then determine referral to genetic counselling for appropriate patients.

Precision medicine is increasingly driving decisions for germline testing. Poly(ADP-ribose) polymerase (PARP) inhibitors, immune checkpoint inhibitors and various other agents now in clinical trials have clinical activity in patients with certain hereditary cancer gene mutations, such as in DNA repair genes.

Patients’ experiences with germline testing can be variable; taking the patient’s current experience into account, considering referral to genetic counselling when needed and offering germline testing for eligible men at repeated intervals if initially declined are important.

Rucaparib and olaparib for the treatment of prostate cancer: A clinician's guide to choice of therapy

OBJECTIVE

This review will provide an overview of the use rucaparib and olaparib in patients with metastatic castration resistant prostate cancer (mCRPC) with the goal to assist the clinician's decision-making process when considering these agents for an individual patient.

DATA SOURCES

Searches were conducted in PubMed, relevant meeting abstracts, clinicaltrials.gov, and United States Food and Drug Administration (FDA) documents to identify literature published through July 1, 2021, related to use of rucaparib and olaparib for treatment of prostate cancer.

DATA SUMMARY

In May 2020, the FDA approved rucaparib and olaparib for treatment of mCRPC that is homologous recombination repair (HRR)-deficient. Both agents are approved for previously-treated patients, but there are notable differences in strength of evidence, outcomes studied, required HRR alteration, and required prior therapies. In patients who qualify for therapy, additional factors that may help guide choice of PARP inhibitor include baseline organ function, drug interaction potential, toxicity profiles, and financial factors.

CONCLUSIONS

Rucaparib and olaparib have the potential to improve outcomes for patients with HRR-deficient mCRPC. Differences in strength of evidence and patient- and drug-specific characteristics will assist the clinician when choosing between agents.

BRCA1 and BRCA2 pathogenic variants and prostate cancer risk: systematic review and meta-analysis

BACKGROUND

BRCA1 and BRCA2 pathogenic variants (PVs) are associated with prostate cancer (PCa) risk, but a wide range of relative risks (RRs) has been reported.

METHODS

We systematically searched PubMed, Embase, MEDLINE and Cochrane Library in June 2021 for studies that estimated PCa RRs for male BRCA1/2 carriers, with no time or language restrictions. The literature search identified 27 studies (BRCA1: n = 20, BRCA2: n = 21).

RESULTS

The heterogeneity between the published estimates was high (BRCA1: I2 = 30%, BRCA2: I2 = 83%); this could partly be explained by selection for age, family history or aggressive disease, and study-level differences in ethnicity composition, use of historical controls, and location of PVs within BRCA2. The pooled RRs were 2.08 (95% CI 1.38-3.12) for Ashkenazi Jewish BRCA2 carriers, 4.35 (95% CI 3.50-5.41) for non-Ashkenazi European ancestry BRCA2 carriers, and 1.18 (95% CI 0.95-1.47) for BRCA1 carriers. At ages <65 years, the RRs were 7.14 (95% CI 5.33-9.56) for non-Ashkenazi European ancestry BRCA2 and 1.78 (95% CI 1.09-2.91) for BRCA1 carriers.

CONCLUSIONS

These PCa risk estimates will assist in guiding clinical management. The study-level subgroup analyses indicate that risks may be modified by age and ethnicity, and for BRCA2 carriers by PV location within the gene, which may guide future risk-estimation studies.

The Feasibility of Implementing Mainstream Germline Genetic Testing in Routine Cancer Care-A Systematic Review

Simple Summary

Germline genetic testing for patients with cancer can have important implications for treatment, preventive options, and for family members. In a mainstream genetic testing pathway, pre-test counseling is performed by non-genetic healthcare professionals, thereby making genetic testing more accessible to all patients who might benefit from it. These mainstream genetic testing pathways are being implemented in different hospitals around the world, and for different cancer types. It is important to evaluate how a mainstream genetic testing pathway can be made sustainable and if quality of genetic care is maintained. We show in this systematic review that it is feasible to incorporate a mainstream genetic testing pathway into routine cancer care while maintaining quality of care. A training procedure for non-genetic healthcare professionals and a close collaboration between genetics and other clinical departments are highly recommended to ensure sustainability.

Abstract

Background: Non-genetic healthcare professionals can provide pre-test counseling and order germline genetic tests themselves, which is called mainstream genetic testing. In this systematic review, we determined whether mainstream genetic testing was feasible in daily practice while maintaining quality of genetic care. Methods: PubMed, Embase, CINAHL, and PsychINFO were searched for articles describing mainstream genetic testing initiatives in cancer care. Results: Seventeen articles, reporting on 15 studies, met the inclusion criteria. Non-genetic healthcare professionals concluded that mainstream genetic testing was possible within the timeframe of a routine consultation. In 14 studies, non-genetic healthcare professionals completed some form of training about genetics. When referral was coordinated by a genetics team, the majority of patients carrying a pathogenic variant were seen for post-test counseling by genetic healthcare professionals. The number of days between cancer diagnosis and test result disclosure was always lower in the mainstream genetic testing pathway than in the standard genetic testing pathway (e.g., pre-test counseling at genetics department). Conclusions: Mainstream genetic testing seems feasible in daily practice with no insurmountable barriers. A structured pathway with a training procedure is desirable, as well as a close collaboration between genetics and other clinical departments.

Analysis of BRCA Germline Mutations in Chinese Prostate Cancer Patients

Recent studies have indicated that prostate cancer (PCa) with BRCA2 mutations is more aggressive. However, these reports mostly focused on Caucasus populations, and large-scale studies on BRCA mutations in Chinese PCa populations remain limited. Herein, we screened, from multiple centers in China, a total of 172 patients with PCa carrying BRCA1/2 germline mutations. The variant distribution and type, associated somatic variant, and frequency of the BRCA germline variants in these patients were analyzed retrospectively. We found that Chinese patients with PCa carrying BRCA1/2 germline mutations were diagnosed at an earlier age, i.e., 67 years (range, 34–89 years), and most had metastatic castration-resistant PCa (mCRPC) (54.65%, 94/172). The top three BRCA variants were frameshift, missense, and splicing variants. The overall pathogenic rates of the BRCA1 and BRCA2 variants were 17.46% (11/63) and 56.55% (82/145), respectively. Among the somatic mutations associated with BRCA2 germline mutations, the highest frequency was for FOXA1 (circulating tumor DNA [ctDNA] sequencing, 7.4%; tissue samples, 52%) and NCOR2 mutations (ctDNA sequencing, 7.4%; tissue samples, 24%); TP53 was the dominant somatic mutation associated with BRCA1 germline mutations (ctDNA sequencing, 25%; tissue samples, 17%). Ultimately, in Chinese patients, PCa with BRCA1/2 germline mutations tends to be more aggressive. Compared with BRCA1, BRCA2 has a higher frequency of germline pathogenic mutations. FOXA1, NCOR2, and TP53 somatic mutations associated with higher BRCA1/2 germline pathogenic mutations. Our description of BRCA germline mutations in the Chinese PCa patients provides more reference data for the precise diagnosis and treatment of Chinese PCa patients.

Clinical Management of Prostate Cancer in High-Risk Genetic Mutation Carriers

Simple Summary

Men with certain genetic differences are at much higher risks of developing metastatic and lethal prostate cancer. With the recent introduction of a new class of medications specifically targeted to these gene repair pathways (PARP inhibitors), it is critical to review the state of the literature surrounding the management of men with prostate cancer who have these genetic differences. We review the existing literature to address common clinical questions pertaining to this population. There is an urgent need for further research regarding clinical management in these scenarios as patients are increasingly seeking out genetic testing and consulting healthcare professionals for guidance.

Abstract

Background: Prostate cancer is a leading cause of death. Approximately one in eight men who are diagnosed with prostate cancer will die of it. Since there is a large difference in mortality between low- and high-risk prostate cancers, it is critical to identify individuals who are at high-risk for disease progression and death. Germline genetic differences are increasingly recognized as contributing to risk of lethal prostate cancer. The objective of this paper is to review prostate cancer management options for men with high-risk germline mutations. Methods: We performed a review of the literature to identify articles regarding management of prostate cancer in individuals with high-risk germline genetic mutations. Results: We identified numerous publications regarding the management of prostate cancer among high-risk germline carriers, but the overall quality of the evidence is low. Conclusions: We performed a review of the literature and compiled clinical considerations for the management of individuals with high-risk germline mutations when they develop prostate cancer. The quality of the evidence is low, and there is an immediate need for further research and the development of consensus guidelines to guide clinical practice for these individuals.

Racial Differences in Prostate Cancer Characteristics and Cancer-Specific Mortality: An Overview

Racial differences of prostate cancer incidence and mortality among Asian, Black, and Caucasian men have been known, however, comprehensive update of this topic is not yet reported. In the present review, an overview of the racial differences in prostate cancer characteristics and cancer-specific mortality is collected and reviewed. Regarding racial differences of incidence and mortality, surprising differences in the incidence of prostate cancer are seen among different populations around the world, with some countries having rates that are 60 to 100 times higher than others. African-American men have a higher incidence of prostate cancer, higher prostate cancer mortality, and are diagnosed with prostate cancer at a younger age than Caucasian American men. Furthermore, race is gaining attention as an important factor to consider for planning active surveillance for localized prostate cancer, especially among African-Americans. In addition, the causes of these differences are being elucidated by genomic profiling. Determinants of racial disparities are multifactorial, including socioeconomic and biologic factors. Although race-specific differences in prostate cancer survival estimates appear to be narrowing over time, there is an ongoing need to continue to understand and mitigate racial factors associated with disparities in health care outcomes.