Contribution of Inherited DNA-Repair Gene Mutations to Hormone-Sensitive and Castrate-Resistant Metastatic Prostate Cancer and Implications for Clinical Outcome

Risk of lymphoid malignancy associated with cancer predisposition genes

We investigated the prevalence of rare inherited pathogenic variants (PV) in 19 cancer predisposition genes regularly included on multi-gene panel testing based on NCCN guidelines and their association with the risk of lymphoid malignancies (LM) overall and by common lymphoma subtypes and multiple myeloma. The study population included newly diagnosed LM cases (N = 6990) and unrelated controls (N = 42,632), excluding individuals with a history of hematologic malignancy. Whole exome sequencing was performed on DNA from whole blood. PV were defined as loss-of-function (i.e., nonsense, frameshift, consensus splice sites) or identified as "pathogenic" or "likely pathogenic" in the ClinVar database. A total of 1816 (3.7%) individuals had a PV across the 19 genes, higher in cases (4.7%) than controls (3.5%). In controls, CHEK2 (1.0%), ATM (0.4%), BRCA2 (0.4%), and BRCA1 (0.3%) had the highest prevalence. ATM (odds ratio [OR] = 1.86, 95% confidence interval [CI]: 1.36-2.49), CHEK2 (OR = 1.74, 95% CI: 1.42-2.13) and TP53 (OR = 9.07, 95% CI: 4.51-18.87) were associated with increased risk of LM overall and were further validated in the UK Biobank. We observed heterogeneity in associations by LM subtype. These results demonstrate that several commonly tested cancer predisposition genes are associated with an increased risk of LM.

Azoospermia/Oligozoospermia and Prostate Cancer Are Increased in Families of Women With Primary Ovarian Insufficiency

Background

Nonobstructive azoospermia (NOA) and primary ovarian insufficiency (POI) have common genetics that may also predispose patients to cancer risk.

Objectives

We hypothesized that NOA or severe oligozoospermia and the risk of male cancers would be higher in families of women with POI.

Methods

Women with POI were identified using International Classification of Disease codes in electronic medical records (1995-2021) from 2 major healthcare systems in Utah and reviewed for accuracy. Using genealogy information in the Utah Population Database, women with POI (n = 392) and their relatives were included if there were at least 3 generations of ancestors available. Men with NOA or severe oligozoospermia (≤5 million/mL) from the Subfertility Health and Assisted Reproduction and the Environment Study were identified in these families and risk was calculated in relatives compared to population rates. The relative risk of prostate and testicular cancer was examined using the Utah Cancer Registry.

Results

There was an increased risk of NOA/severe oligozoospermia in relatives of women with POI among first- (relative risk 2.8 [95% confidence interval 1.1, 6.7]; P = .03), second- (3.1 [1.1, 6.7]; P = .02), and third-degree relatives (1.8 [1.1, 3.1]; P = .03). In these families with POI and NOA/oligozoospermia (n = 21), prostate cancer risk was higher in first- (3.5 [1.1, 8.1]; P = .016) and second-degree relatives (3.1 [1.9, 4.8]; P = .000008).

Conclusion

The data demonstrate excess familial clustering of severe spermatogenic impairment compared to matched population rates, along with higher prostate cancer risk in relatives of women with POI. These findings support a common genetic contribution to POI, spermatogenic impairment, and prostate cancer.

Germline Genetic Testing for Hereditary Breast and Ovarian Cancer: Current Concepts in Risk Evaluation

Our understanding of hereditary breast and ovarian cancer has significantly improved over the past two decades. In addition to BRCA1/2, pathogenic variants in several other DNA-repair genes have been shown to increase the risks of breast and ovarian cancer. The magnitude of cancer risk is impacted not only by the gene involved, but also by family history of cancer, polygenic risk scores, and, in certain genes, pathogenic variant type or location. While estimates of breast and ovarian cancer risk associated with pathogenic variants are available, these are predominantly based on studies of high-risk populations with young age at diagnosis of cancer, multiple primary cancers, or family history of cancer. More recently, breast cancer risk for germline pathogenic variant carriers has been estimated from population-based studies. Here, we provide a review of the field of germline genetic testing and risk evaluation for hereditary breast and ovarian cancers in high-risk and population-based settings.

Men with metastatic prostate cancer carrying a pathogenic germline variant in breast cancer genes: disclosure of genetic test results to relatives

Some patients with metastatic prostate cancer carry a pathogenic germline variant (PV) in a gene, that is mainly associated with an increased risk of breast cancer in women. If they test positive for such a PV, prostate cancer patients are encouraged to disclose the genetic test result to relatives who are at risk in case the carrier status changes the relatives' medical care. Our study aimed to investigate how men who learned they carry a PV in BRCA1, BRCA2, PALB2, CHEK2 or ATM disclosed their carrier status to at-risk relatives and to assess the possible psychological burden for the carrier and their perception of the burden for relatives. In total, 23 men with metastatic prostate cancer carrying a PV completed the IRI questionnaire about family communication; 14 also participated in a semi-structured interview. Patients felt highly confident in discussing the genetic test result with relatives. The diagnosis of prostate cancer was experienced as a burden, whereas being informed about genetic testing results did in most cases not add to this burden. Two patients encountered negative experiences with family communication, as they considered the genetic test result to be more urgent than their relatives. This mixed-methods study shows that metastatic prostate cancer patients with a PV in genes mainly associated with increased risk of breast cancer feel well-equipped to communicate about this predisposition in their families. Carriers felt motivated to disclose their genetic test result to relatives. Most of them indicated that the disclosure was not experienced as a psychological burden.

Genetic and biological drivers of prostate cancer disparities in Black men

Black men with prostate cancer have historically had worse outcomes than white men with prostate cancer. The causes of this disparity in outcomes are multi-factorial, but a potential basis is that prostate cancers in Black men are biologically distinct from prostate cancers in white men. Evidence suggests that genetic and ancestral factors, molecular pathways involving androgen and non-androgen receptor signalling, inflammation, epigenetics, the tumour microenvironment and tumour metabolism are contributing factors to the racial disparities observed. Key genetic and molecular pathways linked to prostate cancer risk and aggressiveness have potential clinical relevance. Describing biological drivers of prostate cancer disparities could inform efforts to improve outcomes for Black men with prostate cancer.

Internet-Based Germline Genetic Testing for Men With Metastatic Prostate Cancer

PURPOSE

Germline mutations in DNA repair genes are present in approximately 10% of men with metastatic prostate cancer (mPC), and guidelines recommend genetic germline testing. Notable barriers exist, including access to genetic counseling, insurance coverage, and out-of-pocket costs. The GENTleMEN study was designed to determine the feasibility of an Internet-based, patient-driven germline genetic testing approach for men with mPC.

PATIENTS AND METHODS

In this prospective cohort study, men with mPC provided informed consent via an Internet-based platform and completed a questionnaire including demographics and family cancer history. Supporting medical data were also collected. Genetic testing was performed using the Color Genomics 30-gene targeted panel of cancer predisposition genes on a mailed saliva sample. Men whose test results identified a germline pathogenic or likely pathogenic variant received results by phone or telehealth genetic counseling; other participants received results by email with an option for phone-based or telehealth genetic counseling.

RESULTS

As of August 18, 2021, 816 eligible men were consented, of whom 68% (551) completed genetic testing, and 8.7% (48 of 551) were found to carry a pathogenic or likely pathogenic variant in a germline DNA repair gene: CHEK2 (17), BRCA2 (15), ATM (6), NBN1 (3), BRCA1 (2), PALB2 (2), PMS2 (2), and MSH6 (1). Participants were more likely to complete the testing process if they were non-Hispanic White, married, highly educated, or from a higher-income bracket.

CONCLUSION

Here, we show the feasibility of delivering germline (inherited) genetic testing by a voluntary, patient-driven, Internet-based platform to men with mPC. Preliminary results show rates of germline DNA repair mutations, consistent with other cohorts. Although feasible for some, reduced steps for participation, more dedicated diverse outreach and participant support, and identification and addressing of additional barriers is needed to ensure equitable access and optimization.

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.

Germline Pathogenic Variants in Cancer Predisposition Genes Among Women With Invasive Lobular Carcinoma of the Breast

PURPOSE

To determine the contribution of germline pathogenic variants (PVs) in hereditary cancer testing panel genes to invasive lobular carcinoma (ILC) of the breast.

MATERIALS AND METHODS

The study included 2,999 women with ILC from a population-based cohort and 3,796 women with ILC undergoing clinical multigene panel testing (clinical cohort). Frequencies of germline PVs in breast cancer predisposition genes (ATM, BARD1, BRCA1, BRCA2, BRIP1, CDH1, CHEK2, PALB2, PTEN, RAD51C, RAD51D, and TP53) were compared between women with ILC and unaffected female controls and between women with ILC and infiltrating ductal carcinoma (IDC).

RESULTS

The frequency of PVs in breast cancer predisposition genes among women with ILC was 6.5% in the clinical cohort and 5.2% in the population-based cohort. In case-control analysis, CDH1 and BRCA2 PVs were associated with high risks of ILC (odds ratio [OR] > 4) and CHEK2, ATM, and PALB2 PVs were associated with moderate (OR = 2-4) risks. BRCA1 PVs and CHEK2 p.Ile157Thr were not associated with clinically relevant risks (OR < 2) of ILC. Compared with IDC, CDH1 PVs were > 10-fold enriched, whereas PVs in BRCA1 were substantially reduced in ILC.

CONCLUSION

The study establishes that PVs in ATM, BRCA2, CDH1, CHEK2, and PALB2 are associated with an increased risk of ILC, whereas BRCA1 PVs are not. The similar overall PV frequencies for ILC and IDC suggest that cancer histology should not influence the decision to proceed with genetic testing. Similar to IDC, multigene panel testing may be appropriate for women with ILC, but CDH1 should be specifically discussed because of low prevalence and gastric cancer risk.

Do BARD1 Mutations Confer an Elevated Risk of Prostate Cancer?

Simple Summary

Current cancer testing gene panels tend to be comprehensive. One of the genes commonly included in the testing panels is BARD1. To establish whether BARD1 mutations predispose to prostate cancer, we sequenced BARD1 in 390 hereditary prostate cancer cases, genotyped 5715 men with unselected prostate cancer and 10,252 controls for three recurrent rare BARD1 variants in Poland. We did not see an elevated prostate risk cancer given p.Q564X truncating mutation, p.R658C missense mutation and p.R659= synonymous variant. Neither variant influenced prostate cancer characteristics or survival. Our study is the first to evaluate the association between BARD1 mutations and prostate cancer susceptibility. It is not justified to inform men about increased prostate cancer risk in case of identification of a BARD1 mutation. However, a female relative of a man with a BARD1 mutation may benefit from this information and be tested, because BARD1 is a breast cancer susceptibility gene.

Abstract

The current cancer testing gene panels tend to be comprehensive rather than site-specific. BARD1 is one of the genes commonly included in the multi-cancer testing panels. Mutations in BARD1 confer an increase in the risk for breast cancer, but it is not studied whether or not they predispose to prostate cancer. To establish if BARD1 mutations also predispose to prostate cancer, we screened BARD1 in 390 Polish patients with hereditary prostate cancer. No truncating mutations were identified by sequencing. We also genotyped 5715 men with unselected prostate cancer, and 10,252 controls for three recurrent BARD1 variants, including p.Q564X, p.R658C and p.R659=. Neither variant conferred elevated risk of prostate cancer (ORs between 0.84 and 1.15, p-values between 0.57 and 0.93) nor did they influence prostate cancer characteristics or survival. We conclude that men with a BARD1 mutation are not at elevated prostate cancer risk. It is not justified to inform men about increased prostate cancer risk in case of identification of a BARD1 mutation. However, a female relative of a man with a BARD1 mutation may benefit from this information and be tested for the mutation, because BARD1 is a breast cancer susceptibility gene.

Current management of metastatic castration-sensitive prostate cancer

Prostate cancer affects one in nine men and once metastatic is incurable. The treatment for metastatic castration-sensitive prostate cancer (mCSPC) has evolved rapidly over the last decade with the addition of upfront intensification with novel hormonal therapies (abiraterone, enzalutamide, apalutamide) or docetaxel in addition to androgen deprivation therapy. In this review, we discuss the phase III studies that lead to the approval of these upfront intensification therapies. We also review the recent approval of relugolix, the first oral, gonadotropin-releasing hormone antagonist for patients with advanced prostate cancer. A comparison of various agents is made and variables that can help in treatment selection are reviewed. We also summarize our current understanding of the role of germline and somatic alterations in the mCSPC setting. Finally, we review the ongoing clinical trials which can change the current treatment paradigm.