Prostate-specific membrane antigen-positron emission tomography (PSMA-PET) of prostate cancer: current and emerging applications

Prostate-specific membrane antigen-positron emission tomography (PSMA-PET) is transforming the management of patients with prostate cancer. In appropriately selected patients, PSMA-PET offers superior sensitivity and specificity compared to conventional imaging (e.g., computed tomography and bone scintigraphy) as well as choline and fluciclovine PET, with the added benefit of consolidating bone and soft tissue evaluation into a single study. Despite being a newly available imaging tool, PSMA-PET has established indications, interpretation guidelines, and reporting criteria, which will be reviewed. The prostate cancer care team, from imaging specialists to those delivering treatment, should have knowledge of physiologic PSMA radiotracer uptake, patterns of disease spread, and the strengths and limitations of PSMA-PET. In this review, current and emerging applications of PSMA-PET, including appropriateness use criteria as well as image interpretation and pitfalls, will be provided with an emphasis on clinical implications.

Salvage Therapy for Prostate Cancer: AUA/ASTRO/SUO Guideline Part II: Treatment Delivery for Non-metastatic Biochemical Recurrence After Primary Radical Prostatectomy

PURPOSE

The summary presented herein covers recommendations on salvage therapy for recurrent prostate cancer intended to facilitate care decisions and aid clinicians in caring for patients who have experienced a recurrence following prior treatment with curative intent. This is Part II of a three-part series focusing on treatment delivery for non-metastatic biochemical recurrence (BCR) after primary radical prostatectomy (RP). Please refer to Part I for discussion of treatment decision-making and Part III for discussion of evaluation and management of recurrence after radiotherapy (RT) and focal therapy, regional recurrence, and oligometastasis.

MATERIALS AND METHODS

The systematic review that informs this Guideline was based on searches in Ovid MEDLINE (1946 to July 21, 2022), Cochrane Central Register of Controlled Trials (through August 2022), and Cochrane Database of Systematic Reviews (through August 2022). Update searches were conducted on July 26, 2023. Searches were supplemented by reviewing electronic database reference lists of relevant articles.

RESULTS

In a collaborative effort between AUA, ASTRO, and SUO, the Salvage Therapy for Prostate Cancer Panel developed evidence- and consensus-based guideline statements to provide guidance for the care of patients who experience BCR after initial definitive local therapy for clinically localized disease.

CONCLUSIONS

Optimizing and personalizing the approach to salvage therapy remains an ongoing area of work in the field of genitourinary oncology and represents an area of research and clinical care that requires well-coordinated, multi-disciplinary efforts.

Phase II Study of Erdafitinib in Patients With Tumors With Fibroblast Growth Factor Receptor Mutations or Fusions: Results From the NCI-MATCH ECOG-ACRIN Trial (EAY131) Subprotocol K2

PURPOSE

Subprotocol K2 (EAY131-K2) of the NCI-MATCH platform trial was an open-label, single-arm, phase II study designed to evaluate the antitumor efficacy of the oral FGFR1-4 inhibitor, erdafitinib, in patients with tumors harboring FGFR1-4 mutations or fusions.

METHODS

Central confirmation of tumor FGFR1-4 mutations or fusions was required for outcome analysis. Patients with urothelial carcinoma were excluded. Enrolled subjects received oral erdafitinib at a starting dose of 8 mg daily continuously until intolerable toxicity or disease progression. The primary end point was objective response rate (ORR) with key secondary end points of safety, progression-free survival (PFS), and overall survival (OS).

RESULTS

Thirty-five patients were enrolled, and 25 patients were included in the primary efficacy analysis as prespecified in the protocol. The median age was 61 years, and 52% of subjects had received ≥3 previous lines of therapy. The confirmed ORR was 16% (4 of 25 [90% CI, 5.7 to 33.0], P = .034 against the null rate of 5%). An additional seven patients experienced stable disease as best-confirmed response. Four patients had a prolonged PFS including two with recurrent WHO grade IV, IDH1-/2-wildtype glioblastoma. The median PFS and OS were 3.6 months and 11.0 months, respectively. Erdafitinib was manageable with no new safety signals.

CONCLUSION

This study met its primary end point in patients with several pretreated solid tumor types harboring FGFR1-3 mutations or fusions. These findings support advancement of erdafitinib for patients with fibroblast growth factor receptor-altered tumors outside of currently approved indications in a potentially tumor-agnostic manner.

Prostate Cancer, Version 3.2024

The NCCN Guidelines for Prostate Cancer include recommendations for staging and risk assessment after a prostate cancer diagnosis and for the care of patients with localized, regional, recurrent, and metastatic disease. These NCCN Guidelines Insights summarize the panel's discussions for the 2024 update to the guidelines with regard to initial risk stratification, initial management of very-low-risk disease, and the treatment of nonmetastatic recurrence.

Phase II Study of Erdafitinib in Patients With Tumors With FGFR Amplifications: Results From the NCI-MATCH ECOG-ACRIN Trial (EAY131) Subprotocol K1

PURPOSE

Despite fibroblast growth factor receptor (FGFR) inhibitors being approved in tumor types with select FGFR rearrangements or gene mutations, amplifications of FGFR represent the most common FGFR alteration across malignancies. Subprotocol K1 (EAY131-K1) of the National Cancer Institute-MATCH platform trial was designed to evaluate the antitumor efficacy of the oral FGFR1-4 inhibitor, erdafitinib, in patients with tumors harboring FGFR1-4 amplification.

METHODS

EAY131-K1 was an open-label, single-arm, phase II study with central confirmation of presence of FGFR1-4 amplification in tumors. Patients with urothelial carcinoma were excluded. Enrolled patients received oral erdafitinib at a starting dose of 8 mg once daily continuously with escalation to 9 mg once daily continuously, on the basis of predefined time point assessments of phosphate levels, until disease progression or intolerable toxicity. The primary end point was centrally assessed objective response rate (ORR), with key secondary end points being 6-month progression-free survival (PFS6), PFS, overall survival (OS), and safety.

RESULTS

Thirty-five patients were enrolled into this study with 18 included in the prespecified primary efficacy analysis. The median age of the 18 patients was 60 years, and 78% had received ≥3 previous lines of therapy. There were no confirmed responses to erdafitinib; however, five patients experienced stable disease (SD) as best response. One patient with an FGFR1-amplified breast cancer had a prolonged PFS >168 days (5.5 months). The median PFS was 1.7 months (90% CI, 1.1 to 1.8 months) and the median OS was 4.2 months (90% CI, 2.3 to 9.3 months). The estimated PFS6 rate was 13.8% (90% CI, 3.3 to 31.6). The majority of toxicities were grade 1 to 2 in nature, although there was one grade 5 treatment-related adverse event.

CONCLUSION

Erdafitinib did not meet its primary end point of efficacy as determined by ORR in treatment-refractory solid tumors harboring FGFR1-4 amplifications. Our findings support that rearrangements and gene mutations, but not amplifications, of FGFR remain the established FGFR alterations with approved indications for FGFR inhibition.

Salvage Therapy for Prostate Cancer: AUA/ASTRO/SUO Guideline Part III: Salvage Therapy After Radiotherapy or Focal Therapy, Pelvic Nodal Recurrence and Oligometastasis, and Future Directions

PURPOSE

The summary presented herein covers recommendations on salvage therapy for recurrent prostate cancer intended to facilitate care decisions and aid clinicians in caring for patients who have experienced a recurrence following prior treatment with curative intent. This is Part III of a three-part series focusing on evaluation and management of suspected non-metastatic recurrence after radiotherapy (RT) and focal therapy, evaluation and management of regional recurrence, management for molecular imaging metastatic recurrence, and future directions. Please refer to Part I for discussion of treatment decision-making and Part II for discussion of treatment delivery for non-metastatic biochemical recurrence (BCR) after radical prostatectomy (RP).

MATERIALS AND METHODS

The systematic review that informs this Guideline was based on searches in Ovid MEDLINE (1946 to July 21, 2022), Cochrane Central Register of Controlled Trials (through August 2022), and Cochrane Database of Systematic Reviews (through August 2022). Update searches were conducted on July 26, 2023. Searches were supplemented by reviewing electronic database reference lists of relevant articles.

RESULTS

In a collaborative effort between AUA, ASTRO, and SUO, the Salvage Therapy for Prostate Cancer Guideline Panel developed evidence- and consensus-based guideline statements to provide guidance for the care of patients who experience BCR after initial definitive local therapy for clinically localized disease.

CONCLUSIONS

Continuous and deliberate efforts for multidisciplinary care in prostate cancer will be required to optimize and improve the oncologic and functional outcomes of patients treated with salvage therapies in the future.

Salvage Therapy for Prostate Cancer: AUA/ASTRO/SUO Guideline Part I: Introduction and Treatment Decision-Making at the Time of Suspected Biochemical Recurrence after Radical Prostatectomy

PURPOSE

The summary presented herein covers recommendations on salvage therapy for recurrent prostate cancer intended to facilitate care decisions and aid clinicians in caring for patients who have experienced a recurrence following prior treatment with curative intent. This is Part I of a three-part series focusing on treatment decision-making at the time of suspected biochemical recurrence (BCR) after radical prostatectomy (RP). Please refer to Part II for discussion of treatment delivery for non-metastatic BCR after RP and Part III for discussion of evaluation and management of recurrence after radiotherapy (RT) and focal therapy, regional recurrence, and oligometastasis.

MATERIALS AND METHODS

The systematic review that informs this Guideline was based on searches in Ovid MEDLINE (1946 to July 21, 2022), Cochrane Central Register of Controlled Trials (through August 2022), and Cochrane Database of Systematic Reviews (through August 2022). Update searches were conducted on July 26, 2023. Searches were supplemented by reviewing electronic database reference lists of relevant articles.

RESULTS

In a collaborative effort between AUA, ASTRO, and SUO, the Salvage Therapy for Prostate Cancer Panel developed evidence- and consensus-based statements to provide guidance for the care of patients who experience BCR after initial definitive local therapy for clinically localized disease.

CONCLUSIONS

Advancing work in the area of diagnostic tools (particularly imaging), biomarkers, radiation delivery, and biological manipulation with the evolving armamentarium of therapeutic agents will undoubtedly present new opportunities for patients to experience long-term control of their cancer while minimizing toxicity.

Three- and Seven-month Prostate-specific Antigen Levels as Prognostic Markers for Overall Survival in Metastatic Hormone-sensitive Prostate Cancer: Results from SWOG S1216, a Phase 3 Randomized Trial of Androgen Deprivation Plus Orteronel or Bicalutamide

BACKGROUND

A robust decrease in prostate-specific antigen (PSA) in response to androgen deprivation therapy (ADT) has been evaluated as a prognostic factor in patients with metastatic hormone-sensitive prostate cancer (mHSPC) since 2006, but the treatment of mHSPC has since evolved to include intensified therapy.

OBJECTIVE

We assessed the association of PSA levels at 3 (PSA-3mo) and 7 (PSA-7mo) mo with overall survival (OS) in patients with mHSPC treated with ADT combined with either bicalutamide or orteronel in the S1216 phase 3 clinical trial.

DESIGN, SETTING, AND PARTICIPANTS

PSA responses to treatment of patients in the S1216 trial were categorized as: complete response (CR) if PSA was ≤0.2 ng/ml, partial response if PSA was >0.2 and ≤4 ng/ml, and no response (NR) if PSA was >4 ng/ml.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

A Cox analysis (adjusted for treatment arm and three stratification factors: performance status, severity of disease, and early vs late induction) was used for OS association. While PSA-7mo association was a prespecified objective, PSA-3mo association was also evaluated.

RESULTS AND LIMITATIONS

A total of 1251 and 1231 patients from the S1216 study were evaluable for PSA-3mo and PSA-7mo, respectively. A PSA-7mo CR was associated with improved OS compared with NR (HR: 0.20; p < 0.0001). A PSA-3mo CR showed a similar association to NR (HR: 0.34; p < 0.0001). The association of a PSA response with survival did not differ by treatment arm at either time point.

CONCLUSIONS

The PSA-3mo and PSA-7mo responses were strongly associated with OS; taken with other emerging prognostic biomarkers, these markers may allow for early identification of patients at the highest risk of death, aid with counseling in clinical practice, and permit design of future clinical trials targeting these patients.

PATIENT SUMMARY

A low prostate-specific antigen level at 3 or 7 mo after starting treatment for metastatic hormone-sensitive prostate cancer predicts longer survival regardless of the first treatment given with androgen deprivation therapy.

TARGET: A Randomized, Noninferiority Trial of a Pretest, Patient-Driven Genetic Education Webtool Versus Genetic Counseling for Prostate Cancer Germline Testing

PURPOSE

Germline genetic testing (GT) is important for prostate cancer (PCA) management, clinical trial eligibility, and hereditary cancer risk. However, GT is underutilized and there is a shortage of genetic counselors. To address these gaps, a patient-driven, pretest genetic education webtool was designed and studied compared with traditional genetic counseling (GC) to inform strategies for expanding access to genetic services.

METHODS

Technology-enhanced acceleration of germline evaluation for therapy (TARGET) was a multicenter, noninferiority, randomized trial (ClinicalTrials.gov identifier: NCT04447703) comparing a nine-module patient-driven genetic education webtool versus pretest GC. Participants completed surveys measuring decisional conflict, satisfaction, and attitudes toward GT at baseline, after pretest education/counseling, and after GT result disclosure. The primary end point was noninferiority in reducing decisional conflict between webtool and GC using the validated Decisional Conflict Scale. Mixed-effects regression modeling was used to compare decisional conflict between groups. Participants opting for GT received a 51-gene panel, with results delivered to participants and their providers.

RESULTS

The analytic data set includes primary outcome data from 315 participants (GC [n = 162] and webtool [n = 153]). Mean difference in decisional conflict score changes between groups was -0.04 (one-sided 95% CI, -∞ to 2.54; P = .01), suggesting the patient-driven webtool was noninferior to GC. Overall, 145 (89.5%) GC and 120 (78.4%) in the webtool arm underwent GT, with pathogenic variants in 15.8% (8.7% in PCA genes). Satisfaction did not differ significantly between arms; knowledge of cancer genetics was higher but attitudes toward GT were less favorable in the webtool arm.

CONCLUSION

The results of the TARGET study support the use of patient-driven digital webtools for expanding access to pretest genetic education for PCA GT. Further studies to optimize patient experience and evaluate them in diverse patient populations are warranted.

Marital Status, Living Arrangement, and Survival among Individuals with Advanced Prostate Cancer in the International Registry for Men with Advanced Prostate Cancer

BACKGROUND

Studies have shown improved survival among individuals with cancer with higher levels of social support. Few studies have investigated social support and overall survival (OS) in individuals with advanced prostate cancer in an international cohort. We investigated the associations of marital status and living arrangements with OS among individuals with advanced prostate cancer in the International Registry for Men with Advanced Prostate Cancer (IRONMAN).

METHODS

IRONMAN is enrolling participants diagnosed with advanced prostate cancer (metastatic hormone-sensitive prostate cancer, mHSPC; castration-resistant prostate cancer, CRPC) from 16 countries. Participants in this analysis were recruited between July 2017 and January 2023. Adjusting for demographics and tumor characteristics, the associations were estimated using Cox regression and stratified by disease state (mHSPC, CRPC), age (<70, ≥70 years), and continent of enrollment (North America, Europe, Other).

RESULTS

We included 2,119 participants with advanced prostate cancer, of whom 427 died during up to 5 years of follow-up (median 6 months). Two-thirds had mHSPC. Most were married/in a civil partnership (79%) and 6% were widowed. Very few married participants were living alone (1%), while most unmarried participants were living alone (70%). Married participants had better OS than unmarried participants [adjusted HR: 1.44; 95% confidence interval (CI): 1.02-2.02]. Widowed participants had the worst survival compared with married individuals (adjusted HR: 1.89; 95% CI: 1.22-2.94).

CONCLUSIONS

Among those with advanced prostate cancer, unmarried and widowed participants had worse OS compared with married participants.

IMPACT

This research highlighted the importance of social support in OS within this vulnerable population.

PROMISE Registry: A prostate cancer registry of outcomes and germline mutations for improved survival and treatment effectiveness

BACKGROUND

Recently approved treatments and updates to genetic testing recommendations for prostate cancer have created a need for correlated analyses of patient outcomes data via germline genetic mutation status. Genetic registries address these gaps by identifying candidates for recently approved targeted treatments, expanding clinical trial data examining specific gene mutations, and understanding effects of targeted treatments in the real-world setting.

METHODS

The PROMISE Registry is a 20-year (5-year recruitment, 15-year follow-up), US-wide, prospective genetic registry for prostate cancer patients. Five thousand patients will be screened through an online at-home germline testing to identify and enroll 500 patients with germline mutations, including: pathogenic or likely pathogenic variants and variants of uncertain significance in genes of interest. Patients will be followed for 15 years and clinical data with real time patient reported outcomes will be collected. Eligible patients will enter long-term follow-up (6-month PRO surveys and medical record retrieval). As a virtual study with patient self-enrollment, the PROMISE Registry may fill gaps in genetics services in underserved areas and for patients within sufficient insurance coverage.

RESULTS

The PROMISE Registry opened in May 2021. 2114 patients have enrolled to date across 48 US states and 23 recruiting sites. 202 patients have met criteria for long-term follow-up. PROMISE is on target with the study's goal of 5000 patients screened and 500 patients eligible for long-term follow-up by 2026.

CONCLUSIONS

The PROMISE Registry is a novel, prospective, germline registry that will collect long-term patient outcomes data to address current gaps in understanding resulting from recently FDA-approved treatments and updates to genetic testing recommendations for prostate cancer. Through inclusion of a broad nationwide sample, including underserved patients and those unaffiliated with major academic centers, the PROMISE Registry aims to provide access to germline genetic testing and to collect data to understand disease characteristics and treatment responses across the disease spectrum for prostate cancer with rare germline genetic variants.

Pain and Its Association with Survival for Black and White Individuals with Advanced Prostate Cancer in the United States

Bone pain is a well-known quality-of-life detriment for individuals with prostate cancer and is associated with survival. This study expands previous work into racial differences in multiple patient-reported dimensions of pain and the association between baseline and longitudinal pain and mortality. This is a prospective cohort study of individuals with newly diagnosed advanced prostate cancer enrolled in the International Registry for Men with Advanced Prostate Cancer (IRONMAN) from 2017 to 2023 at U.S. sites. Differences in four pain scores at study enrollment by race were investigated. Cox proportional hazards models and joint longitudinal survival models were fit for each of the scale scores to estimate HRs and 95% confidence intervals (CI) for the association with all-cause mortality. The cohort included 879 individuals (20% self-identifying as Black) enrolled at 38 U.S. sites. Black participants had worse pain at baseline compared with White participants, most notably a higher average pain rating (mean 3.1 vs. 2.2 on a 10-point scale). For each pain scale, higher pain was associated with higher mortality after adjusting for measures of disease burden, particularly for severe bone pain compared with no pain (HR, 2.47; 95% CI: 1.44-4.22). The association between pain and all-cause mortality was stronger for participants with castration-resistant prostate cancer compared with those with metastatic hormone-sensitive prostate cancer and was similar among Black and White participants. Overall, Black participants reported worse pain than White participants, and more severe pain was associated with higher mortality independent of clinical covariates for all pain scales.

SIGNIFICANCE

Black participants with advanced prostate cancer reported worse pain than White participants, and more pain was associated with worse survival. More holistic clinical assessments of pain in this population are needed to determine the factors upon which to intervene to improve quality of life and survivorship, particularly for Black individuals.

Addressing gaps in healthcare provider knowledge regarding germline testing for prostate cancer through development and testing of a virtual genetics board

BACKGROUND

Germline testing is important in prostate cancer and evaluation can be complex.

METHODS

We instituted a monthly multi-disciplinary virtual genetics tumor board (7/2021-3/2022). Participants and panelists were surveyed on usefulness and acceptability.

RESULTS

101 participants attended a session, and 77 follow-up surveys were completed. Over 90% participants and 100% panelists endorsed usefulness of the case discussions and usability of the technology. The majority felt it provided new information they will use.

CONCLUSIONS

A multidisciplinary genetics board was successfully developed to address complexity in prostate cancer genetics. The virtual platform may enhance dissemination of expertise where there are regional gaps.

Phase 1b study of enzalutamide plus CC-115, a dual mTORC1/2 and DNA-PK inhibitor, in men with metastatic castration-resistant prostate cancer (mCRPC)

BACKGROUND

CC-115, a dual mTORC1/2 and DNA-PK inhibitor, has promising antitumour activity when combined with androgen receptor (AR) inhibition in pre-clinical models.

METHODS

Phase 1b multicentre trial evaluating enzalutamide with escalating doses of CC-115 in AR inhibitor-naive mCRPC patients (n = 41). Primary endpoints were safety and RP2D. Secondary endpoints included PSA response, time-to-PSA progression, and radiographic progression.

RESULTS

Common adverse effects included rash (31.7% Grades 1-2 (Gr); 31.7% Gr 3), pruritis (43.9% Gr 1-2), diarrhoea (37% Gr 1-2), and hypertension (17% Gr 1-2; 9.8% Gr 3). CC-115 RP2D was 5 mg twice a day. In 40 evaluable patients, 80% achieved ≥50% reduction in PSA (PSA50), and 58% achieved ≥90% reduction in PSA (PSA90) by 12 weeks. Median time-to-PSA progression was 14.7 months and median rPFS was 22.1 months. Stratification by PI3K alterations demonstrated a non-statistically significant trend towards improved PSA50 response (PSA50 of 94% vs. 67%, p = 0.08). Exploratory pre-clinical analysis suggested CC-115 inhibited mTOR pathway strongly, but may be insufficient to inhibit DNA-PK at RP2D.

CONCLUSIONS

The combination of enzalutamide and CC-115 was well tolerated. A non-statistically significant trend towards improved PSA response was observed in patients harbouring PI3K pathway alterations, suggesting potential predictive biomarkers of response to a PI3K/AKT/mTOR pathway inhibitor.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT02833883.

Poly(ADP-ribose) Polymerase Inhibitor Combinations in First-Line Metastatic Castration-Resistant Prostate Cancer: Increasing Toxicity With Unclear Benefits

Positive phase III trials are not truly practice changing if they do not accurately inform on the best options for patients

ASSESSMENT OF CELL SURFACE TARGETS IN METASTATIC PROSTATE CANCER: EXPRESSION LANDSCAPE AND MOLECULAR CORRELATES

Therapeutic approaches targeting proteins on the surface of cancer cells have emerged as an important strategy for precision oncology. To fully capitalize on the potential impact of drugs targeting surface proteins, detailed knowledge about the expression patterns of the target proteins in tumor tissues is required. In castration-resistant prostate cancer (CRPC), agents targeting prostate-specific membrane antigen (PSMA) have demonstrated clinical activity. However, PSMA expression is lost in a significant number of CRPC tumors, and the identification of additional cell surface targets is necessary in order to develop new therapeutic approaches. Here, we performed a comprehensive analysis of the expression and co-expression patterns of trophoblast cell-surface antigen 2 (TROP2), delta-like ligand 3 (DLL3), and carcinoembryonic antigen-related cell adhesion molecule 5 (CEACAM5) in CRPC samples from a rapid autopsy cohort. We show that DLL3 and CEACAM5 exhibit the highest expression in neuroendocrine prostate cancer (NEPC), while TROP2 is expressed across different CRPC molecular subtypes, except for NEPC. We observed variable intra-tumoral and inter-tumoral heterogeneity and no dominant metastatic site predilections for TROP2, DLL3, and CEACAM5. We further show that AR amplifications were associated with higher expression of PSMA and TROP2 but lower DLL3 and CEACAM5 levels. Conversely, PSMA and TROP2 expression was lower in RB1-altered tumors. In addition to genomic alterations, we demonstrate a tight correlation between epigenetic states, particularly histone H3 lysine 27 methylation (H3K27me3) at the transcriptional start site and gene body of TACSTD2 (encoding TROP2), DLL3, and CEACAM5, and their respective protein expression in CRPC patient-derived xenografts. Collectively, these findings provide novel insights into the patterns and determinants of expression of TROP2, DLL3, and CEACAM5 with important implications for the clinical development of cell surface targeting agents in CRPC.

Metastatic Bladder Cancer Expression and Subcellular Localization of Nectin-4 and Trop-2 in Variant Histology: A Rapid Autopsy Study

BACKGROUND

Nectin-4 and Trop-2 are transmembrane targets of FDA-approved antibody-drug conjugates (ADC) Enfortumab-vedotin (EV) and Sacituzumab govitecan (SG), respectively, for the treatment of metastatic urothelial carcinoma (mUC). The expression and role of Nectin-4 and Trop-2 in mUC variant histology is poorly described.

MATERIALS AND METHODS

We evaluate membranous and cytoplasmic protein expression, and mRNA levels of Nectin-4 and Trop-2 within matched primary and metastatic mUC samples to determine heterogeneity of ADC targets in mUC variants.

RESULTS

Patients with mUC were consented for rapid autopsy immediately after death. Tissues from matched primary and metastatic lesions were collected. A total of 67 specimens from 20 patients were analyzed: 27 were UC, 17 plasmacytoid (PUC), 18 UC with squamous differentiation (UCSD), and 5 neuroendocrine (NE); 10 from primary and 57 from metastatic sites. All histology except NE expressed moderate-high levels of Nectin-4 and Trop-2 by both immunohistochemistry and RNAseq. Nectin-4 demonstrated prominent cytoplasmic staining in metastatic PUC and UCSD. Trop-2 demonstrated strong cytoplasmic and membrane staining in primary and metastatic tumors. Interestingly, Nectin-4 and Trop-2 expression are positively correlated at both mRNA and protein levels.

CONCLUSION

UC and non-NE variants express notable level of Nectin-4 and Trop-2 in both primary and metastatic lesions. Membrane staining of Nectin-4 and Trop-2 is present but cytoplasmic staining is a more common event in both mUC and mUC variant histology. These findings support evaluation of EV and SG in heavily treated variant histology BC and urge attention on the clinical relevance of cytoplasmic localization of ADC targets.

Tumor Mutational Burden Testing in Solid Tumors

A 58-year-old man with diabetes, chronic kidney disease, and JAK2-positive myeloproliferative neoplasm is referred for newly diagnosed oligometastatic prostate cancer with substantial urinary symptoms. What would you do next?

Quality of life in the year after new diagnosis with advanced prostate cancer for Black and White individuals living in the US

PURPOSE

To assess differences in baseline and longitudinal quality of life among Black and White individuals in the US with advanced prostate cancer.

METHODS

Secondary analysis of data from the International Registry for Men with Advanced Prostate Cancer (IRONMAN) including US participants newly diagnosed with advanced prostate cancer and identifying their race as Black or White from 2017 to 2023. Participants completed the EORTC QLQ-C30 Quality of Life (QoL) Survey at study enrollment and every 3 months thereafter for up to 1 year of follow-up reporting 15 scale scores ranging from 0 to 100 (higher functioning and lower symptom scores represent better quality of life). Linear mixed effects models with race and month of questionnaire completion were fit for each scale, and model coefficients were used to assess differences in baseline and longitudinal QoL by race.

RESULTS

Eight hundred and seventy-nine participants were included (20% identifying as Black) at 38 US sites. Compared to White participants at baseline, Black participants had worse constipation (mean 6.3 percentage points higher; 95% CI 2.9-9.8), financial insecurity (5.7 (1.4-10.0)), and pain (5.1 (0.9-9.3)). QoL decreased over time similarly by race; most notably, role functioning decreased by 0.7 percentage points (95% CI -0.8, -0.5) per month.

CONCLUSION

There are notable differences in quality of life at new diagnosis of advanced prostate cancer for Black and White individuals, and quality of life declines similarly in the first year for both groups. Interventions that address specific aspects of quality of life in these patients could meaningfully improve the overall survivorship experience.

Prostate Cancer, Version 4.2023, NCCN Clinical Practice Guidelines in Oncology

The NCCN Guidelines for Prostate Cancer provide a framework on which to base decisions regarding the workup of patients with prostate cancer, risk stratification and management of localized disease, post-treatment monitoring, and treatment of recurrence and advanced disease. The Guidelines sections included in this article focus on the management of metastatic castration-sensitive disease, nonmetastatic castration-resistant prostate cancer (CRPC), and metastatic CRPC (mCRPC). Androgen deprivation therapy (ADT) with treatment intensification is strongly recommended for patients with metastatic castration-sensitive prostate cancer. For patients with nonmetastatic CRPC, ADT is continued with or without the addition of certain secondary hormone therapies depending on prostate-specific antigen doubling time. In the mCRPC setting, ADT is continued with the sequential addition of certain secondary hormone therapies, chemotherapies, immunotherapies, radiopharmaceuticals, and/or targeted therapies. The NCCN Prostate Cancer Panel emphasizes a shared decision-making approach in all disease settings based on patient preferences, prior treatment exposures, the presence or absence of visceral disease, symptoms, and potential side effects.

Sarcomatoid Urothelial Carcinoma Is Associated With Limited Response to Neoadjuvant Chemotherapy and Poor Oncologic Outcomes After Radical Cystectomy

INTRODUCTION

To examine oncologic outcomes and response to neoadjuvant chemotherapy (NAC) in patients with sarcomatoid urothelial carcinoma (SUC) treated with radical cystectomy (RC).

MATERIALS AND METHODS

We retrospectively queried our institutional database (2003-18) and Surveillance, Epidemiology, and End Results (SEER)-Medicare (2004-2015) for patients with cT2-4, N0-2, M0 SUC and conventional UC (CUC) treated with RC. Clinicopathologic characteristics were described using descriptive statistics (t test, χ2-test and log-rank-test for group comparison). Overall (OS) and recurrence-free-survival (RFS) after RC were estimated with the Kaplan Meier method and associations with OS were evaluated with Cox proportional hazards models.

RESULTS

We identified 38 patients with SUC and 287 patients with CUC in our database, and 190 patients with SUC in SEER-Medicare. In the institutional cohort, patients with SUC versus CUC had higher rates of pT3/4 stage (66% vs. 35%, P < 0.001), lower rates of ypT0N0 (6% vs. 35%, P = .02), and worse median OS (17.5 vs. 120 months, P < .001). Further, patients with SUC in the institutional versus SEER-Medicare cohort had similar median OS (17.5 vs. 21 months). In both cohorts, OS was comparable between patients with SUC undergoing NAC+RC vs. RC alone (17.5 vs. 18.4 months, P = .98, institutional cohort; 24 vs. 20 months, P = .56, SEER cohort). In Cox proportional hazards models for the institutional RC cohort, SUC was independently associated with worse OS (HR 2.3, CI 1.4-3.8, P = .001).

CONCLUSION

SUC demonstrates poor pathologic response to NAC and worse OS compared with CUC, with no OS benefit associated with NAC. A unique pattern of rapid abdominopelvic cystic recurrence was identified.

Poly-ADP ribose polymerase inhibitor and androgen receptor signaling inhibitor for all comers for first-line treatment of metastatic castration-resistant prostate cancer: is gene sequencing out?

PURPOSE OF REVIEW

The landscape for first-line therapy (1L) of metastatic castration-resistant prostate cancer (mCRPC) is rapidly shifting. In the past 2 years, three phase 3 trials have examined the addition of a poly-ADP ribose polymerase inhibitor (PARPi) to an androgen receptor-signaling inhibitor (ARSI) in 1L. The FDA and the EMA recently considered whether one of these combinations should be approved for "all comers." Here, we review the trial designs, assays for homologous recombination repair mutations (HRRm) and BRCA mutations (BRCAm), and predictive capacity of mutational status on treatment efficacy to understand the basis for the FDA decision.

RECENT FINDINGS

The phase 3 trials, PROpel, MAGNITUDE, and TALAPRO-2, each compared PARPi and ARSI to placebo (PBO) plus ARSI. PROpel and TALAPRO-2 (cohort 1) included all comers (i.e., no prospective biomarker selection), while MAGNITUDE prospectively assigned patients to HRRm and HRR nonmutated cohorts and TALAPRO-2 (cohort 2) included only those with HRRm. Radiographic progression-free survival (rPFS) was the primary endpoint, and overall survival (OS) was a key secondary endpoint in all trials. Although rPFS with a PARPi and ARSI was improved versus PBO with ARSI, major conclusions differed.

SUMMARY

The nuances and interpretation of these trials provide an understanding of the rationale for the FDA's decision to restrict the approval of olaparib and abiraterone and prednisone (AAP) as 1L therapy to those with biomarker evidence of BRCAm.

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.

Management of patients with advanced prostate cancer-metastatic and/or castration-resistant prostate cancer: Report of the Advanced Prostate Cancer Consensus Conference (APCCC) 2022

BACKGROUND

Innovations in imaging and molecular characterisation together with novel treatment options have improved outcomes in advanced prostate cancer. However, we still lack high-level evidence in many areas relevant to making management decisions in daily clinical practise. The 2022 Advanced Prostate Cancer Consensus Conference (APCCC 2022) addressed some questions in these areas to supplement guidelines that mostly are based on level 1 evidence.

OBJECTIVE

To present the voting results of the APCCC 2022.

DESIGN, SETTING, AND PARTICIPANTS

The experts voted on controversial questions where high-level evidence is mostly lacking: locally advanced prostate cancer; biochemical recurrence after local treatment; metastatic hormone-sensitive, non-metastatic, and metastatic castration-resistant prostate cancer; oligometastatic prostate cancer; and managing side effects of hormonal therapy. A panel of 105 international prostate cancer experts voted on the consensus questions.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

The panel voted on 198 pre-defined questions, which were developed by 117 voting and non-voting panel members prior to the conference following a modified Delphi process. A total of 116 questions on metastatic and/or castration-resistant prostate cancer are discussed in this manuscript. In 2022, the voting was done by a web-based survey because of COVID-19 restrictions.

RESULTS AND LIMITATIONS

The voting reflects the expert opinion of these panellists and did not incorporate a standard literature review or formal meta-analysis. The answer options for the consensus questions received varying degrees of support from panellists, as reflected in this article and the detailed voting results are reported in the supplementary material. We report here on topics in metastatic, hormone-sensitive prostate cancer (mHSPC), non-metastatic, castration-resistant prostate cancer (nmCRPC), metastatic castration-resistant prostate cancer (mCRPC), and oligometastatic and oligoprogressive prostate cancer.

CONCLUSIONS

These voting results in four specific areas from a panel of experts in advanced prostate cancer can help clinicians and patients navigate controversial areas of management for which high-level evidence is scant or conflicting and can help research funders and policy makers identify information gaps and consider what areas to explore further. However, diagnostic and treatment decisions always have to be individualised based on patient characteristics, including the extent and location of disease, prior treatment(s), co-morbidities, patient preferences, and treatment recommendations and should also incorporate current and emerging clinical evidence and logistic and economic factors. Enrolment in clinical trials is strongly encouraged. Importantly, APCCC 2022 once again identified important gaps where there is non-consensus and that merit evaluation in specifically designed trials.

PATIENT SUMMARY

The Advanced Prostate Cancer Consensus Conference (APCCC) provides a forum to discuss and debate current diagnostic and treatment options for patients with advanced prostate cancer. The conference aims to share the knowledge of international experts in prostate cancer with healthcare providers worldwide. At each APCCC, an expert panel votes on pre-defined questions that target the most clinically relevant areas of advanced prostate cancer treatment for which there are gaps in knowledge. The results of the voting provide a practical guide to help clinicians discuss therapeutic options with patients and their relatives as part of shared and multidisciplinary decision-making. This report focuses on the advanced setting, covering metastatic hormone-sensitive prostate cancer and both non-metastatic and metastatic castration-resistant prostate cancer.

TWITTER SUMMARY

Report of the results of APCCC 2022 for the following topics: mHSPC, nmCRPC, mCRPC, and oligometastatic prostate cancer.

TAKE-HOME MESSAGE

At APCCC 2022, clinically important questions in the management of advanced prostate cancer management were identified and discussed, and experts voted on pre-defined consensus questions. The report of the results for metastatic and/or castration-resistant prostate cancer is summarised here.

Management of Patients with Advanced Prostate Cancer. Part I: Intermediate-/High-risk and Locally Advanced Disease, Biochemical Relapse, and Side Effects of Hormonal Treatment: Report of the Advanced Prostate Cancer Consensus Conference 2022

BACKGROUND

Innovations in imaging and molecular characterisation and the evolution of new therapies have improved outcomes in advanced prostate cancer. Nonetheless, we continue to lack high-level evidence on a variety of clinical topics that greatly impact daily practice. To supplement evidence-based guidelines, the 2022 Advanced Prostate Cancer Consensus Conference (APCCC 2022) surveyed experts about key dilemmas in clinical management.

OBJECTIVE

To present consensus voting results for select questions from APCCC 2022.

DESIGN, SETTING, AND PARTICIPANTS

Before the conference, a panel of 117 international prostate cancer experts used a modified Delphi process to develop 198 multiple-choice consensus questions on (1) intermediate- and high-risk and locally advanced prostate cancer, (2) biochemical recurrence after local treatment, (3) side effects from hormonal therapies, (4) metastatic hormone-sensitive prostate cancer, (5) nonmetastatic castration-resistant prostate cancer, (6) metastatic castration-resistant prostate cancer, and (7) oligometastatic and oligoprogressive prostate cancer. Before the conference, these questions were administered via a web-based survey to the 105 physician panel members ("panellists") who directly engage in prostate cancer treatment decision-making. Herein, we present results for the 82 questions on topics 1-3.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Consensus was defined as ≥75% agreement, with strong consensus defined as ≥90% agreement.

RESULTS AND LIMITATIONS

The voting results reveal varying degrees of consensus, as is discussed in this article and shown in the detailed results in the Supplementary material. The findings reflect the opinions of an international panel of experts and did not incorporate a formal literature review and meta-analysis.

CONCLUSIONS

These voting results by a panel of international experts in advanced prostate cancer can help physicians and patients navigate controversial areas of clinical management for which high-level evidence is scant or conflicting. The findings can also help funders and policymakers prioritise areas for future research. Diagnostic and treatment decisions should always be individualised based on patient and cancer characteristics (disease extent and location, treatment history, comorbidities, and patient preferences) and should incorporate current and emerging clinical evidence, therapeutic guidelines, and logistic and economic factors. Enrolment in clinical trials is always strongly encouraged. Importantly, APCCC 2022 once again identified important gaps (areas of nonconsensus) that merit evaluation in specifically designed trials.

PATIENT SUMMARY

The Advanced Prostate Cancer Consensus Conference (APCCC) provides a forum to discuss and debate current diagnostic and treatment options for patients with advanced prostate cancer. The conference aims to share the knowledge of international experts in prostate cancer with health care providers and patients worldwide. At each APCCC, a panel of physician experts vote in response to multiple-choice questions about their clinical opinions and approaches to managing advanced prostate cancer. This report presents voting results for the subset of questions pertaining to intermediate- and high-risk and locally advanced prostate cancer, biochemical relapse after definitive treatment, advanced (next-generation) imaging, and management of side effects caused by hormonal therapies. The results provide a practical guide to help clinicians and patients discuss treatment options as part of shared multidisciplinary decision-making. The findings may be especially useful when there is little or no high-level evidence to guide treatment decisions.

Genetic Testing Among Patients with High-Risk Breast, Ovarian, Pancreatic, and Prostate Cancers

BACKGROUND

The National Comprehensive Cancer Network recommends genetic testing in patients with potentially hereditary breast, ovarian, pancreatic, and prostate cancers (HBOPP). Knowledge of genetic mutations impacts decisions about screening and treatment.

METHODS

A retrospective cohort study of 28,586 HBOPP patients diagnosed from 2013 to 2019 was conducted using a linked administrative-cancer database in the Seattle-Puget Sound SEER area. Guideline-concordant testing (GCT) was assessed annually according to guideline updates. Frequency of testing according to patient/cancer characteristics was evaluated using chi-squared tests, and factors associated with receipt of genetic testing were identified using multivariable logistic regression.

RESULTS

Testing occurred in 17% of HBOPP patients, increasing from 9% in 2013 to 21% in 2019 (p < 0.001). Ovarian cancer had the highest testing (40%) and prostate cancer the lowest (4%). Age < 50, female sex, non-Hispanic White race, commercial insurance, urban location, family history of HBOPP, and triple negative breast cancer (TNBC) were associated with increased testing (all p < 0.05). GCT increased from 38% in 2013 to 44% in 2019, and was highest for early age at breast cancer diagnosis, TNBC, male breast cancer, and breast cancer with family history of HBOPP (all > 70% in 2019), and lowest for metastatic prostate cancer (6%).

CONCLUSIONS

The frequency of genetic testing for HBOPP cancer has increased over time. Though GCT is high for breast cancer, there are gaps in concordance among patients with other cancers. Increasing provider and patient education, genetic counseling, and insurance coverage for testing among HBOPP patients may improve guideline adherence.

Bipolar androgen therapy plus olaparib in men with metastatic castration-resistant prostate cancer

BACKGROUND

Bipolar androgen therapy (BAT) results in rapid fluctuation of testosterone (T) between near-castrate and supraphysiological levels and has shown promise in metastatic castration-resistant prostate cancer (mCRPC). Its clinical effects may be mediated through induction of DNA damage, and preclinical studies suggest synergy with PARP inhibitors.

PATIENTS AND METHODS

This was a single-center, Phase II trial testing olaparib plus BAT (T cypionate/enanthate 400 mg every 28 days) with ongoing androgen deprivation. Planned recruitment was 30 subjects (equal proportions with/without homologous recombination repair [HRR] gene mutations) with mCRPC post abiraterone and/or enzalutamide. The primary objective was to determine PSA50 response (PSA decline ≥50% from baseline) rate at 12-weeks. The primary analysis utilized the entire (intent-to-treat [ITT]) cohort, with those dropping out early counted as non-responders. Secondary/exploratory analyses were in those treated beyond 12-weeks (response-evaluable cohort).

RESULTS

Thirty-six patients enrolled and 6 discontinued prior to response assessment. In the ITT cohort, PSA50 response rate at 12-weeks was 11/36 (31%; 95% CI 17-48%), and 16/36 (44%, 95% CI 28-62%) had a PSA50 response at any time on-study. After a median follow-up of 19 months, the median clinical/radiographic progression-free survival in the ITT cohort was 13.0 months (95% CI 7-17). Clinical outcomes were similar regardless of HRR gene mutational status.

CONCLUSIONS

BAT plus olaparib is associated with high response rates and long PFS. Clinical benefit was observed regardless of HRR gene mutational status.

Inherited risk for prostate cancer (PCa): Following the natural history of men with high-risk genetics using multiparametric MRI (mpMRI)

390

Background: PCa has inherited risk factors including high genetic risk variants such as BRCA1/2, HOXB13, and DNA mismatch repair genes. mpMRI has been shown to be effective for detection and staging of localized PCa. This study follows participants (prts), born biologically male, without a diagnosis of PCa with known germline pathogenic or likely pathogenic variants (PV) in BRCA1/2, MLH1, MSH2, MSH6, PMS2, EPCAM, HOXB13, ATM, NBN, TP53, CHEK2, PALB2, RAD51C/D, BRIP1, or FANCA-FANCM (NCT03805919). Methods: Up to 500 eligible prts 30-75 years old (yo) with a documented germline PV will enroll. Prts undergo biennial clinical exam and mpMRI, and annual PSA monitoring and are followed at 12-month intervals to determine PSA, prostate cancer diagnosis, and/or disease/survival status until death. Indication for prostate biopsy includes clinical or imaging findings. Biopsy specimens undergo molecular analyses. Results: To date, 175 prts have been enrolled: 169 (97%) White, 3 Hispanic (2%), 1 African American (1%), 1 Asian (1%), and 1 biethnic (1%). Median age is 47 yo. The most common monoallelic PV are: 48.6% BRCA2, 25.1% BRCA1, 6.3% CHEK2 and 5.7% MSH2. PVs in ATM, PALB2, HOXB13, PMS2, MLH1, MSH6, BRIP1, EPCAM and RAD51D are ≤4%. One subject carries three distinct PVs ( BRCA2, CHEK2, BRIP1). Indication for biopsy was found in 26.3% of prts with 22/46 (47.8%) with a PIRADS 4 lesion, 6/46 (13.0%) PIRADS 3 lesion, 12/46 (26.1%) elevated PSA (median=2.8 ng/mL) or 6/46 (13.0%) due to clinical discretion. Adenocarcinoma was diagnosed on 13/39 (33.3%) biopsies with median age at diagnosis=59 yo. 9/13 (69%) prts had a PSA <3 ng/ml at diagnosis. Nine prts were diagnosed with ISUP Grade Group (GG) 1, 3 with GG2, and 1 with GG3. Eight prts opted for active surveillance (AS), 2 for radiation therapy (RT), and 3 for prostatectomy (RP). Two prts on AS converted to definitive treatment (one RP and one RT) due to progression in GG on the year 1 AS biopsy. Conclusions: mpMRI screening in men with germline PV can be used for diagnosis and monitoring of PCa and facilitates detection below conventional PSA thresholds in a high genetic risk setting. Access to genetic testing and other variables need to be addressed in underrepresented minorities. Correlative studies, including cfDNA and PBMCs, are ongoing. Clinical trial information: NCT03805919 . [Table: see text]

PROMISE Registry: A prostate cancer registry of outcomes and germline mutations for improved survival and treatment effectiveness

TPS274

Background: Recent updates to genetic testing recommendations and approved treatment options for prostate cancer (PCa) patients (pts) have clarified the need for comprehensive genetic registries. Germline DNA damage repair (DDR) defects are present in over 10% of pts who develop metastatic castration-resistant prostate cancer (mCRPC) while 5-10% pts with localized PCa have germline pathogenic variants in DDR genes. NCCN guidelines have recently expanded to address genetic testing to include high risk localized, node positive and metastatic disease, in addition to family cancer history criteria. In May 2020, the FDA approved 2 PARP inhibitors for mCRPC treatment. Genetic registries can address the critical need to identify pts for recently approved targeted treatments, understand real-world effects of targeted therapies, and expand clinical trials examining less common mutations. PROMISE is a prospective genetic registry equipped to meet these needs. Methods: 5000 PCa pts will be screened via the online study portal and at-home germline testing to identify and enroll 500 eligible pts with germline pathogenic variants, likely pathogenic variants, and variants of uncertain significance (VUS) in the genes of interest: ATM, ATR, BARD1, BRCA1, BRCA2, BRIP1, CHEK2, FAM175A, GEN1, HOXB13, MRE11A, MLH1, MSH2, MSH6, PALB2, PMS2, PTEN, RAD51C, RAD51D, TP53 and XRCC2. Additional genes may be added as evidence emerges. Eligible pts must be assigned male at birth and have documented PCa through tissue biopsy, and/or PSA >100ng/dL, and/or radiographic evidence of disease. Pts with or without prior genetic testing, including those with known pathogenic variants, are encouraged to enroll. Exclusion criteria are: inability or unwillingness to provide information for eligibility and incomplete inclusion criteria. Following germline testing, pts will be offered genetic counseling and periodic newsletters with updates on treatments and clinical trials. Every 6 months, eligible pts will complete a patient-reported outcome (PRO) survey (EORTC QLQ-C30) and updated medical records will be obtained for clinical data abstraction. Eligible pts will enter long-term follow-up. The primary endpoint is the creation of a prospective genetic registry of PCa pts. Additional endpoints include: frequency of pathogenic or likely pathogenic germline variants of interest, recruitment of a control group with a VUS in the genes of interest, association between disease characteristics and germline testing results, comparison of PROs between disease subpopulations, longitudinal outcomes, and overall survival. Study duration is 20 years (recruitment: 5 years, follow-up: 15 years). PROMISE is recruiting at 23 US sites. 1829 subjects have enrolled in the screening phase with 189 eligible for long-term follow-up. PROMISE is sponsored and managed by the Prostate Cancer Clinical Trials Consortium. Clinical trial information: NCT04995198 .

Factors related to men’s experience with prostate cancer germline testing

128

Background: Indications for prostate cancer (PCA) germline testing (GT) have greatly expanded, with genetics delivery being implemented in a variety of ways. Here we evaluate factors related to men’s experience with genetic evaluation (GE) in the PCA Genetic Risk, Experience, and Support Study – PROGRESS Registry. Methods: Men took online surveys that covered demographics, PCA history, mode of GE, and measures of patient-reported outcomes (PROs) (satisfaction [Demarco 2004] [Score 6-30; higher=greater satisfaction], decisional conflict [O’Connor 1995] [Score 16-80; higher=greater conflict], attitude re: GT [Marteau 2001] [Score 1-7; higher=perceived benefit], and knowledge of cancer genetics [Erblich 2005] [% correct of 15 questions]). Data were summarized using descriptive statistics. Multiple linear regression modeling assessed relationships between characteristics, mode of GE, and PROs. Significance level was a nominal α = 0.05 (SAS v9.4). Results: PROGRESS reached accrual goal (n=500). Characteristics (among n=414): 87.7% White, 6.0% Asian, 87.7% bachelor’s degree or higher. Among n=422, 46.9% reported PCA diagnosis. Among n=416 who reported genetic results, 27.9% had pathogenic/likely pathogenic variants (P/LPV), 14.7% had VUS, and 9.9% did not know. Mode of GE was delivered: by genetics professional (GP) (24.9% in-person,10.5% phone, 6% telehealth), by doctor (21.1%), from website (20.8%), by genetics lab (5%), and by video (10.8%). Some reported not having pretest discussion (23.7%) or not knowing (8.1%). From multiple regression models, several factors including race, mode of GE, education, and genetic results were related to PROs. Conclusions: Several factors may impact men’s experience with PCA GE, deserving further study into root causes particularly related to diverse populations and genetics care delivery models to support men and their families. [Table: see text]

Differential responses to taxanes and PARP inhibitors in ATM- versus BRCA2-mutated metastatic castrate-resistant prostate cancer

BACKGROUND

PARP (poly(ADP-ribose) polymerase) inhibitors (PARPi) are now standard of care in metastatic castrate-resistant prostate cancer (mCRPC) patients with select mutations in DNA damage repair (DDR) pathways, but patients with ATM- and BRCA2 mutations may respond differently to PARPi. We hypothesized that differences may also exist in response to taxanes, which may inform treatment sequencing decisions.

METHODS

mCRPC patients (N = 158) with deleterious ATM or BRCA2 mutations who received taxanes, PARPi, or both were retrospectively identified from 11 US academic centers. Demographic, treatment, and survival data were collected. Kaplan-Meier analyses were performed and Cox hazard ratios (HR) were calculated for progression-free survival (PFS) as well as overall survival (OS), from time of first taxane or PARPi therapy.

RESULTS

Fifty-eight patients with ATM mutations and 100 with BRCA2 mutations were identified. Fourty-four (76%) patients with ATM mutations received taxane only or taxane before PARPi, while 14 (24%) received PARPi only or PARPi before taxane. Patients with ATM mutations had longer PFS when taxane was given first versus PARPi given first (HR: 0.74 [95% confidence interval [CI]: 0.37-1.50]; p = 0.40). Similarly, OS was longer in patients with ATM mutations who received taxane first (HR: 0.56 [CI: 0.20-1.54]; p = 0.26). Among patients with BRCA2 mutations, 51 (51%) received taxane first and 49 (49%) received PARPi first. In contrast, patients with BRCA2 mutations had longer PFS when PARPi was given first versus taxane given first (HR: 0.85 [CI: 0.54-1.35]; p = 0.49). Similarly, OS was longer in patients with BRCA2 mutations who received PARPi first (HR: 0.75 [CI: 0.41-1.37]; p = 0.35).

CONCLUSIONS

Our retrospective data suggest differential response between ATM and BRCA2 mutated prostate cancers in terms of response to PARPi and to taxane chemotherapy. When considering the sequence of PARPi versus taxane chemotherapy for mCRPC with DDR mutations, ATM, and BRCA2 mutation status may be helpful in guiding choice of initial therapy.

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.

A Phase 1/2 Study of Rapamycin and Cisplatin/Gemcitabine for Treatment of Patients With Muscle-Invasive Bladder Cancer

INTRODUCTION

Cisplatin-based neoadjuvant chemotherapy (NAC) followed by cystectomy is the standard for muscle-invasive bladder cancer (MIBC), however, NAC confers only a small survival benefit and new strategies are needed to increase its efficacy. Pre-clinical data suggest that in response to DNA damage the tumor microenvironment (TME) adopts a paracrine secretory phenotype dependent on mTOR signaling which may provide an escape mechanism for tumor resistance, thus offering an opportunity to increase NAC effectiveness with mTOR blockade.

PATIENTS & METHODS

We conducted a phase I/II clinical trial to assess the safety and efficacy of gemcitabine-cisplatin-rapamycin combination. Grapefruit juice was administered to enhance rapamycin pharmacokinetics by inhibiting intestinal enzymatic degradation. Phase I was a dose determination/safety study followed by a single arm Phase II study of NAC prior to radical cystectomy evaluating pathologic response with a 26% pCR rate target.

RESULTS

In phase I, 6 patients enrolled, and the phase 2 dose of 35 mg rapamycin established. Fifteen patients enrolled in phase II; 13 were evaluable. Rapamycin was tolerated without serious adverse events. At the preplanned analysis, the complete response rate (23%) did not meet the prespecified level for continuing and the study was stopped due to futility. With immunohistochemistry, successful suppression of the mTOR signaling pathway in the tumor was achieved while limited mTOR activity was seen in the TME.

CONCLUSION

Adding rapamycin to gemcitabine-cisplatin therapy for patients with MIBC was well tolerated but failed to improve therapeutic efficacy despite evidence of mTOR blockade in tumor cells. Further efforts to understand the role of the tumor microenvironment in chemotherapy resistance is needed.

NCCN Guidelines® Insights: Prostate Cancer, Version 1.2023

The NCCN Guidelines for Prostate Cancer address staging and risk assessment after a prostate cancer diagnosis and include management options for localized, regional, recurrent, and metastatic disease. The NCCN Prostate Cancer Panel meets annually to reevaluate and update their recommendations based on new clinical data and input from within NCCN Member Institutions and from external entities. These NCCN Guidelines Insights summarizes much of the panel's discussions for the 4.2022 and 1.2023 updates to the guidelines regarding systemic therapy for metastatic prostate cancer.

[The incidence and time distribution of early transient intraocular pressure elevation after penetrating canaloplasty]

Objective: To report the incidence and time distribution of early transient intraocular pressure (IOP) elevation after penetrating canaloplasty. Methods: Retrospective case series study. Data of patients treated by penetrating canaloplasty for glaucoma in the Eye Hospital of Wenzhou Medical University from June 2015 to March 2020 were collected. Early transient IOP elevation was defined as an increase of IOP to over 21 mmHg on the first week to the third month after surgery followed by a decrease to 21 mmHg or less within 3 months. Main outcome measures included IOP, quantity of medication use, the occurrence time and duration of IOP elevation. Generalized estimating equations were used for statistical analysis, and measurement data with non-normal distribution was represented as M (Q₁, Q₃). Results: A total of 277 patients (315 eyes) achieved 360-degree catheterization of the canal successfully, and 299 eyes (94.9%) completed the postoperative 6-month follow-up. Thirty-four eyes (10.8%) had persistently high IOP, so the surgical treatment failed in them. Consequently, 234 patients (265 eyes) were enrolled in the analyses, including 161 males (184 eyes) and 73 females (81 eyes). The median age was 42 (26, 54) years, the mean preoperative IOP was (37.7±11.1) mmHg, and the mean number of drugs used was 3 (2, 4). The incidence of early transient IOP elevation was 43.0% (114/265) in all enrolled eyes, 42.7% (35/82) in eyes with primary open angle glaucoma, 37.8% (17/45) in eyes with primary angle closure glaucoma, 27.7% (13/47) in eyes with congenital glaucoma and 53.8% (49/91) in eyes with secondary glaucoma. The IOP began to increase on the first to fourth week in 91.2% (104/114) of eyes with early transient IOP elevation and reached the peak [21.3 mmHg to 54.8 mmHg; mean, (32.4±8.2) mmHg] in 88.6% (101/114) on the first to fifth week after surgery. The IOP elevation lasted for no more than 4 weeks in 69.3% (79/114) of eyes. Conclusions: Over 40.0% of patients with penetrating canaloplasty may experience postoperative transient IOP elevation. The incidence is relatively high in secondary glaucoma but low in congenital glaucoma. Most of the elevations and peak IOP occur within 1-4 weeks after surgery.

Depression screening and use of supportive care services in prostate cancer

219

Background: Patients with prostate cancer (PC) have high rates of depression (15-20%), which is associated with worse oncologic outcomes. The PHQ-9 is commonly used in depression screening, but men with depression may present differently than women, and male-specific screening tools such as the Gotland Male Depression Scale (GMDS) have also been developed and validated. The use of supportive care services in men with PC and depression is not well-described. Methods: Men with ≥1 Urology or Medical Oncology clinic visit for PC in the prior 6 months were emailed the PHQ-9 and GMDS every 60 days. Men who screened positive (score ≥10 on PHQ-9 or ≥13 on GMDS, consistent with moderate to severe depression) were contacted by phone to discuss the positive screen; during that conversation patients were offered a referral to an oncology social worker for a formal needs assessment and connection to supportive care services. Patient characteristics and use of supportive care services (palliative care, psychiatry, counseling, support groups, or spiritual health) at baseline and as a result of study screening were collected by survey and chart review. Results: Between 6/2021-12/2021, 201 men enrolled (Table). 184 completed ≥2 screens with mean follow-up 6.5 months (SD 1.3). 31 men (15.4%) had ≥1 positive PHQ-9 screen and 11 (5.5%) had ≥1 positive GMDS screen, 9 of whom also screened positive on the PHQ-9. Of the 33 men offered clinical social work referrals based on PHQ-9 or GMDS screening, 12 (36%) initially accepted and 7 (21%) ultimately met with social work. Of these 7 men, two ultimately received ongoing supportive counseling from social work, two were referred to support groups or peers in the community, and one was referred to financial services; the remaining two men were not followed longitudinally or referred to any services by the social worker, but were given the option to re-contact the social worker as needed. For the two patients who screened positive on the GMDS but not the PHQ-9, one declined social work referral, and one initially accepted but never scheduled an appointment. Conclusions: Use of supportive care services in men with PC was low, including when services were actively offered as a result of depression screening. Beyond the PHQ-9, the GMDS did not identify any men who engaged in supportive care services. More work is needed to optimally identify men with PC who may benefit from supportive care services and barriers to use.[Table: see text]

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.

Technology-enhanced AcceleRation of Germline Evaluation for Therapy (TARGET): A randomized controlled trial of a pretest patient-driven webtool vs. genetic counseling for prostate cancer germline testing

BACKGROUND

Germline testing has an increasingly important role in prostate cancer care. However, a relative shortage of genetic counselors necessitates alternate strategies for delivery of pre-test education for germline testing. This study, funded by the Prostate Cancer Foundation, seeks to address the need for novel methods of delivery of pre-test germline education beyond traditional germline counseling to facilitate informed patient decision-making for germline testing.

METHODS

This is a two-armed randomized controlled trial (RCT) with a target enrollment of 173 participants with prostate cancer per study arm (total anticipated n = 346). Patients who meet criteria for germline testing based on tumor features, family history or Ashkenazi Jewish ancestry are being recruited from 5 US sites including academic, private practice and Veterans healthcare settings. Consenting participants are randomized to the interactive pretest webtool or germline counseling with assessment of key patient-reported outcomes involved in informed decision-making for germline germline testing.

RESULTS

Participants complete surveys at baseline, after pretest education/counseling, and following disclosure of germline germline results. The primary outcome of the study is decisional conflict for germline testing. Secondary outcomes include germline knowledge, satisfaction, uptake of germline testing, and understanding of results.

CONCLUSION

Our hypothesis is that the web-based germline education tool is non-inferior to traditional germline counseling regarding key patient-reported outcomes involved in informed decision-making for germline testing. If proven, the results would support deploying the webtool across various practice settings to facilitate pre-test germlines education for individuals with prostate cancer and developing collaborative care strategies with germline counseling.

CLINICALTRIALS

gov Identifier: NCT04447703.

Trial in progress: Durvalumab and olaparib for the treatment of prostate cancer in men predicted to have a high neoantigen load

TPS5099

Background: Approximately 30% of patients (pts) treated with definitive surgical and/or radiation therapy for localized prostate adenocarcinoma develop biochemical recurrence (BCR). The optimal time to initiate androgen deprivation therapy (ADT) for such patients is controversial and depends on patient and provider preference, absolute PSA value, and PSA doubling time (PSADT), which has been associated with time to metastasis. Because the time from BCR to metastasis can be long in many cases, strategies allowing pts to avoid ADT while extending metastasis-free survival are desirable. Prior studies have shown that a high tumor neoantigen load correlates with response to anti-PD(L)1. We hypothesized that PARP inhibitor-induced genomic instability may sensitize tumors to anti-PD(L)1 through: i) increasing mutational burden and subsequent tumor neoantigen formation, and/or ii) through activation of other immunogenic pathways (e.g. the STING pathway). This trial investigates an ADT-sparing approach for men predicted to have high neoantigen load and who have BCR prostate cancer. Methods: This is a phase 2 clinical trial testing durvalumab (1500 mg IV every 4 weeks) and olaparib (300 mg PO twice a day) (one cycle = 4 weeks) in men with BCR (PSADT≤10 months) whose tumors are predicted to have high neoantigen load based on: biallelic CDK12 mutations (Cohort A), mismatch repair deficiency (MMRd)/high microsatellite instability (MSI-H) (Cohort B), or loss of function mutations in homologous recombination repair (HRR) genes (Cohort C). Cohorts A and B will receive 3 cycles of durvalumab followed by 3 cycles of the combination of durvalumab and olaparib. Given the proven efficacy of olaparib in prostate cancer patient whose tumors posses an HRR gene mutation, Cohort C will receive 6 full cycles of the combination. Ten patients will be enrolled in each cohort (total n = 30) at two collaborating sites. This study was designed to provide preliminary efficacy data across eligible cohorts, with a primary objective of estimating the proportion of pts with an undetectable PSA at 12 months within each cohort. Secondary objectives include safety, proportion of patients with ≥50% decline in PSA from baseline and quality of life measures. Correlative studies will assess blood and tissue molecular biomarkers for association with outcomes. The study is open with two patients enrolled at the time of abstract submission. Clinical trial information: NCT04336943.

Longitudinal screening for depression and anxiety in prostate cancer (PC) and association with disease and treatment factors

5023

Background: Untreated depression and anxiety are associated with worse outcomes in patients with cancer. Despite recommendations for longitudinal screening, many patients are only assessed at the start of care. Men with PC often experience many phases of disease or treatment over a span of years, and androgen deprivation therapy (ADT) is associated with mood changes and depression. How depressive or anxiety symptoms fluctuate in men with PC, influenced by disease and treatment factors, is not well-described. Methods: Men with ≥1 Urology or Medical Oncology clinic visit for PC in the prior 6 months were emailed the PHQ-9 and GAD-7 depression and anxiety screening tools every 60 days; a score of ≥10 (moderate to severe symptoms) on either was considered a positive screen. Baseline characteristics and disease/treatment changes (PSA, radiographic, or biopsy progression, treatment change or start, or discontinuation of treatment due to lack of efficacy or toxicity) were collected by survey and chart review. We report early findings of factors associated with a positive screen or change in screening status with χ2 and forward stepwise binary logistic regression (model inputs: receipt of ADT or disease/treatment change during study, and variables previously associated with depression or anxiety: age, race, marital status, education, income, history of psychiatric disorder, use of psychoactive medication, time since diagnosis, and localized, biochemically recurrent, or metastatic disease). Results: From 6/2021-12/2021, 201 men enrolled. At baseline, 50.7% had localized, 18.9% biochemically recurrent, and 30.3% metastatic disease; 40.8% were on ADT; 30.8% had a history of psychiatric disorder (22.9% depression, 19.9% anxiety, 9.0% other); and 24.9% were on psychoactive medication (19.9% antidepressant, 8.5% anxiolytic, 2.0% antipsychotic). 184 men completed at least 2 screens with mean follow-up 6.5 months (SD 1.3). 32 men (15.9%) screened positive at least once (15.4% PHQ-9, 4.5% GAD-7), of which half (N = 16) initially screened negative and later positive. Changing from a negative to positive screen was more likely when a disease/treatment change occurred during the study (18.3% vs 4.5%, p = 0.003). A higher proportion of men on ADT screened positive, especially if newly started during the study or in the 60 days preceding (35.7% new ADT vs 24.7% continuing ADT vs 8.0% no ADT, p = 0.002). In fully adjusted multivariable analyses, factors associated with a positive screen were history of psychiatric disorder (OR 6.3, 95% CI 2.6-15.4, p < 0.001), receipt of ADT (OR 3.8, 95% CI 1.5-9.5, p = 0.005), and lower income bracket (OR 1.7, 95% CI 1.3-2.5, p = 0.002). Conclusions: Longitudinal screening for depression and anxiety in PC identifies men who initially screen negative. Symptoms are associated with ADT and disease or treatment changes, which may inform optimal screening practices.

Clinical impact of PSMA PET in patients with biochemically recurrent prostate cancer after locoregional definitive therapy

e17009

Background: [68Ga]-PSMA-11 positron emission tomography (PSMA PET) detects sites of biochemically recurrent prostate cancer (BCR) at higher rates than conventional imaging. We hypothesized that PSMA PET would lead to high change in management (CIM) rates in this setting. Methods: We prospectively recruited patients (pts) with BCR, defined as confirmed PSA > 0.2 ng/mL > 6 weeks post-surgery or PSA ≥2 ng/mL above nadir post-radiation therapy, to undergo Ga-68 PSMA-11 PET. Some also had equivocal lesions on CT, MRI, bone scan, or fluciclovine PET obtained prior to PSMA PET. Pre-PET intended treatment, PSA (ng/mL), and PSA doubling time (PSAdt, months) from most recent 3 values were recorded prior to imaging. Post-PET treatment (intended or actual) was collected from medical record. CIM was categorized as major (change in or addition of treatment modality) vs minor (change within treatment modality, such as altered radiation field). Any lesion with uptake above blood pool was interpreted as positive for prostate cancer by an experienced PET reader (DLC). All values were represented as the median [interquartile range, IQR]. Kruskal Wallis analysis tested for significant differences among groups. Results: 44 pts with BCR age 71 [10] with Gleason scores (GS) at diagnosis of 6 (N = 2), 7 (N = 23), 8 (N = 5), and 9 (N = 13) enrolled, 14/44 with equivocal lesions on conventional imaging. 42 had post-PSMA PET treatment decisions available in medical records for CIM analysis. Time from PSA nadir to PSA at time of PSMA PET was 5 [7.25] months. PSMA PET was positive in 33 (8/33 with equivocal lesions on prior imaging; 7 local disease only; 11 regional nodal metastases, 2/11 also with local disease; and 15 with distant metastases, 4/15 also with local disease, 9/15 with regional nodal metastases), negative in 6, and equivocal in 5 pts. Of those with distant metastases, 8 had oligometastases, defined as 3 or fewer distinct sites (1 site = single nodal region or single bone lesion), 4 in bones and 4 in distant nodes. CIM rate was 71% (30/42) overall, 65.5% (16/29 major, 3/29 minor) in pts with BCR and negative conventional imaging; 84.6% (11/13, all major) in pts with equivocal lesions on conventional imaging. Of the patients with major CIM, a treatment modality was added in 21/27, modality switched in 3/27, and a modality removed in 3/27. PSA was significantly lower (p = 0.04) for those with negative or equivocal PSMA PET (0.5 [2.7]) than those with localized disease (4.1 [2.8]), regional nodal (1.1 [3.4]) or distant metastases (3.8 [5.3]), but not PSAdt (p = 0.2, negative/equivocal PET 5 [6.5], localized 15 [36], regional nodal metastases 11 [13], distant metastases 6 [6]). Conclusions: PSMA PET may impact decision making in pts with BCR after treatment of localized prostate cancer, particularly for those with equivocal findings on conventional imaging, regardless of clinical risk at diagnosis. Clinical trial information: NCT04777071.

Rates of germline genetic testing and DNA damage response mutations found through population-based recruitment of men with incident metastatic prostate cancer

10501

Background: Approximately 10% of men with metastatic prostate cancer (mPC) have germline DNA damage response gene mutations (gDDRm), indicating candidacy for precision treatment. Consequently, national guidelines recommend germline genetic testing be offered to all men with mPC. It is currently unclear what the rates of testing are in the community, and barriers to testing are not well understood. We conducted a population-based study to better understand current rates of germline genetic testing in men with newly diagnosed mPC, and to determine whether removing major barriers of cost and access could expand uptake of germline genetic testing. Methods: This is a prospective observational study that identifies men ages 35-79y with mPC residing in a 13-county area of Washington State through the Surveillance, Epidemiology, and End Results (SEER) program (NCT04254133). Men with new diagnoses of mPC are contacted by mailed invitation and follow-up phone inquiry. Interested men are then invited to provide informed consent and complete a questionnaire about personal and family health history. A saliva collection kit for a 30-gene targeted panel of cancer predisposition genes (Color Genomics) is mailed to participants’ homes free of charge. Results are issued by phone and/or email with genetic counseling support, including discussion about cascade genetic testing if relevant. Results: As of Feb 9, 2022, 484 men with incident mPC diagnosed 1/2018-6/2021 were identified through SEER. 430 men were reached via a letter to their home address sent > 3 months after diagnosis. 175 of 430 (40.6%) men expressed interest and completed the questionnaire, the majority preferring to complete testing through mail after a phone-initiated introduction to the study. 164 of 175 men completed the consent process and were eligible. Of these 164 men, 45 (27.4%) reported prior genetic testing, and reports were requested and reviewed to ensure adequate testing. Ultimately, 121 of 164 (73.8%) participants initiated and 101/121 (83.5%) have completed genetic testing through the study. Nine percent (9/101) of participants completing testing as part of the study were found to have gDDRm. Conclusions: We used a population-based approach to understand the proportion of men with mPC undergoing germline genetic testing through clinical care, and the subsequent uptake of genetic testing when access and cost barriers are removed. The uptake of guideline-based germline genetic testing among men with mPC in the community prior to study enrollment is only 27.4%. With study interventions in the form of free testing through mail, and phone-based support, 83.5% of men in this community successfully completed testing. Further work in this study will aim to elucidate and attempt to eliminate other barriers in germline genetic testing to further improve testing rates in this community.

Inherited TP53 Variants and Risk of Prostate Cancer

BACKGROUND

Inherited germline TP53 pathogenic and likely pathogenic variants (gTP53) cause autosomal dominant multicancer predisposition including Li-Fraumeni syndrome (LFS). However, there is no known association of prostate cancer with gTP53.

OBJECTIVE

To determine whether gTP53 predisposes to prostate cancer.

DESIGN, SETTING, AND PARTICIPANTS

This multi-institutional retrospective study characterizes prostate cancer incidence in a cohort of LFS males and gTP53 prevalence in a prostate cancer cohort.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

We evaluated the spectrum of gTP53 variants and clinical features associated with prostate cancer.

RESULTS AND LIMITATIONS

We identified 31 prostate cancer cases among 163 adult LFS males, including 26 of 54 aged ≥50 yr. Among 117 LFS males without prostate cancer at the time of genetic testing, six were diagnosed with prostate cancer over a median (interquartile range [IQR]) of 3.0 (1.3-7.2) yr of follow-up, a 25-fold increased risk (95% confidence interval [CI] 9.2-55; p < 0.0001). We identified gTP53 in 38 of 6850 males (0.6%) in the prostate cancer cohort, a relative risk 9.1-fold higher than that of population controls (95% CI 6.2-14; p < 0.0001; gnomAD). We observed hotspots at the sites of attenuated variants not associated with classic LFS. Two-thirds of available gTP53 prostate tumors had somatic inactivation of the second TP53 allele. Among gTP53 prostate cancer cases in this study, the median age at diagnosis was 56 (IQR: 51-62) yr, 44% had Gleason ≥8 tumors, and 29% had advanced disease at diagnosis.

CONCLUSIONS

Complementary analyses of prostate cancer incidence in LFS males and gTP53 prevalence in prostate cancer cohorts suggest that gTP53 predisposes to aggressive prostate cancer. Prostate cancer should be considered as part of LFS screening protocols and TP53 considered in germline prostate cancer susceptibility testing.

PATIENT SUMMARY

Inherited pathogenic variants in the TP53 gene are likely to predispose men to aggressive prostate cancer.

Virtual genetics board for enhancing knowledge and practice of prostate cancer genetic testing: The ENGAGEMENT study

184

Background: With the increasing indications for germline testing for prostate cancer (PCA), there is a growing need for a spectrum of providers to develop working knowledge and understand considerations of germline testing and genetic counseling. A virtual genetics board was developed to provide case-based discussion of PCA germline testing, standard of care and clinical trial management, hereditary cancer management, and genetic counseling. Methods: A virtual genetics board was launched including experts in GU medical oncology, prostate cancer genetics, radiation oncology, urology, clinical trials, genetic counseling, and molecular oncology. Conferences are held monthly, with cases covering metastatic PCA, high-risk disease, early-stage PCA, or PCA screening. Participants complete a baseline survey of demographic information and cancer genetics knowledge. Post-conference survey includes retaking knowledge questions and feedback on cases and Zoom format. Results: At the time of this report, 57 participants have engaged in the virtual genetics board. Participants include genetic counselors (21%), nurse practitioners (21%), medical oncologists (14%), researchers/scientists (14%), nurses (9%), urologists (5%), radiation oncologists (4%), and other specialties. Practice settings include academic centers (49%), public hospitals (16%), private hospitals (11%), and other settings. The baseline survey was completed by 55 participants, and post-conference survey by 34 participants. Knowledge scores increased regarding cancer inheritance, rates of mutations in metastatic PCA, BRCA2-related cancers, risk of PCA for HOXB13 carriers, and risk for PCA in African American males. Feedback was positive, with over 90% favorable responses on usability of technology, usefulness of case discussions, and relevance to informational needs. Conclusions: Initial results support a virtual genetics board to increase PCA genetic evaluation knowledge. The ENGAGEMENT study is ongoing with monthly live case discussions that are also recorded for on-demand viewing; registration is available at www.prostategenetics.com/engagement.[Table: see text]

PROMISE Registry: A prostate cancer registry of outcomes and germline mutations for improved survival and treatment effectiveness

TPS191

Background: Recent updates to genetic testing recommendations and approved treatment options for prostate cancer (PCa) patients (pts) have clarified the need for comprehensive genetic registries. Germline DNA damage repair (DDR) defects are present in over 10% of pts who develop metastatic castration-resistant prostate cancer (mCRPC) while 5-10% of pts with localized PCa have germline pathogenic variants in DDR genes. NCCN guidelines have recently expanded to address genetic testing to include high risk localized, node positive and metastatic disease, in addition to family cancer history criteria. In May 2020, the FDA approved 2 PARP inhibitors for mCRPC treatment. Genetic registries can address the critical need to identify pts for recently approved targeted treatments, understand real-world effects of targeted therapies, and expand clinical trials examining less common mutations. PROMISE is a prospective genetic registry equipped to meet these needs. Methods: 5,000 PCa pts will be screened via the online study portal and at-home germline testing to identify and enroll 500 eligible pts with germline pathogenic variants, likely pathogenic variants, and variants of uncertain significance (VUS) in the genes of interest: ATM, ATR, BRCA1, BRCA2, BRIP1, CHEK2, FAM175A, GEN1, HOXB13, MRE11A, MLH1, MSH2, MSH6, NBN, PALB2, PMS2, PTEN, RAD51C, RAD51D, TP53 and XRCC2. Additional genes may be added as evidence emerges. Eligible pts must be assigned male at birth and have documented PCa through tissue biopsy, and/or PSA >100ng/dL, and/or radiographic evidence of disease. Pts with or without prior genetic testing, including those with known pathogenic variants, are encouraged to enroll. Exclusion criteria are: inability or unwillingness to provide information for eligibility and incomplete inclusion criteria. Following germline testing, all pts will be offered genetic counseling and periodic newsletters with updates on treatments and clinical trials. Every 6 months, eligible pts will complete a patient-reported outcome (PRO) survey (EORTC QLQ-C30) and updated medical records will be obtained for clinical data abstraction. Eligible pts will enter long-term follow-up. The primary endpoint is the creation of a prospective genetic registry of PCa pts. Additional endpoints include: frequency of pathogenic or likely pathogenic germline variants of interest, recruitment of a control group with a VUS in the genes of interest, association between disease characteristics and germline testing results, comparison of PROs between disease subpopulations, longitudinal outcomes, and overall survival. Study duration will be 20 years (active recruitment: 5 years, follow-up: 15 years). PROMISE is recruiting at 10 US sites and has 282 subjects enrolled in the screening phase to date. PROMISE is sponsored and managed by the Prostate Cancer Clinical Trials Consortium. Clinical trial information: NCT04995198.

Phase 2 trial of CV301 vaccine plus atezolizumab (Atezo) in advanced urothelial carcinoma (aUC)

511

Background: PD(L)1 inhibitors can achieve durable responses in aUC but only in a minority of patients (pts). Combination strategies with agents that “prime and stimulate” the immune system may improve outcomes. CV301 comprises 2 recombinant poxviruses, Modified Vaccinia Ankara (MVA) and Fowlpox (FPV), encoding the human transgenes for CEA, MUC-1, and a Triad of Co-stimulatory Molecules (TRICOM: ICAM-1, LFA-3, and B7-1). MVA-CV301 is used for priming and FPV-CV301 is used for booster doses. Preliminarily, BN-platform vaccine plus PD-(L)1 inhibitors exhibited synergistic preclinical anti-tumor efficacy and the combination of CV301 and anti-PD-(L)1 agent demonstrated an acceptable safety profile. We hypothesized that this combination would be safe and effective in cisplatin-ineligible or platinum-refractory pts with aUC. Methods: A Phase 2, single-arm multicenter trial was designed to study CV301 + atezo as 1st-line treatment in pts with aUC ineligible for cisplatin-based chemotherapy regardless of PD-L1 status (Cohort 1; C1) and in pts progressing on/after platinum-based chemotherapy (Cohort 2; C2). MVA-CV301 was given subcutaneously (SC) on Days 1 and 22 and FPV-CV301 SC from day 43 every 21 days for 4 doses, then every 6 weeks until 6 months, then every 12 weeks until 2 years. Atezo 1200mg IV was given every 21 days. Primary endpoint: objective response rate (ORR). Secondary endpoints: OS, PFS, response duration, AEs and antigen-specific T-cell responses to CEA and MUC-1 by ELISPOT. Using 1-sided α 2.5%/cohort, a 2-stage design with 14/19 and 13/22 stage 1/2 subjects, respectively, will achieve ≥70% power if the true ORR for C1 is 43% and C2 is 33%. 3 C1 and 2 C2 responders were required in stage 1 to move forward. Results: 43 evaluable pts were enrolled and received therapy: 19 in C1; 24 in C 2. Overall, 9 pts experienced ≥ Grade 3 AEs related to the combination of treatment: 5 in C1, and 4 in C2. In C1, 1 pt had partial response (PR), for ORR 5.3% (90%CI: 0.3, 22.6) and 5 (26.3%, 90%CI: 11.0, 47.6) had stable disease (SD) as best response. In C2, 1pt had CR and 1 had PR, for ORR 8.3% (90%CI: 1.5, 24.0) and 3 (12.5%, 90%CI: 3.5, 29.2) had SD as best response. Median PFS and OS in C1 were 2.0 mo and 13.8 mo, and in C2 1.95 and 8.13 mo, respectively. The trial was halted for futility. Responding pts in C2 exhibited T-cell responses to CEA and pts with SD exhibited responses to MUC-1. Conclusions: CV301 + atezo exhibited an acceptable safety profile but did not demonstrate sufficient efficacy in pts with aUC as 1st-line therapy in cisplatin-ineligible pts or in the platinum-refractory setting. The development of effective vaccines to generate robust and durable responses as single agents and/or combined with anti-PD(L)1 remains an unmet need in aUC. Clinical trial information: NCT03628716.

Trial in progress: Durvalumab and olaparib for the treatment of prostate cancer in men predicted to have a high neoantigen load

TPS202

Background: Approximately 30% of patients (pts) treated with definitive surgical and/or radiation therapy for localized prostate adenocarcinoma develop biochemical recurrence (BCR). The optimal time to initiate androgen deprivation therapy (ADT) for such patients is controversial and depends on patient and provider preference, absolute PSA value, and PSA doubling time (PSADT), which has been associated with time to metastasis. Because the time from BCR to metastasis can be long in many cases, strategies allowing pts to avoid ADT while extending metastasis-free survival are desirable. Prior studies have shown that a high tumor neoantigen load correlates with response to anti-PD(L)1. We hypothesized that PARP inhibitor-induced genomic instability may sensitize tumors to anti-PD(L)1 through: i) increasing mutational burden and subsequent tumor neoantigen formation, and/or ii) through activation of other immunogenic pathways (e.g. the STING pathway). This trial investigates an ADT-sparing approach for men predicted to have high neoantigen load and who have BCR prostate cancer. Methods: This is a phase 2 clinical trial testing durvalumab (1500 mg IV every 4 weeks) and olaparib (300 mg PO twice a day) (one cycle = 4 weeks) in men with BCR (PSADT≤10 months) whose tumors are predicted to have high neoantigen load based on: biallelic CDK12 mutations (Cohort A), mismatch repair deficiency (MMRd)/high microsatellite instability (MSI-H) (Cohort B), or loss of function mutations in homologous recombination repair (HRR) genes (Cohort C). Cohorts A and B will receive 3 cycles of durvalumab followed by 3 cycles of the combination of durvalumab and olaparib. Given the proven efficacy of olaparib in prostate cancer patient whose tumors posses an HRR gene mutation, Cohort C will receive 6 full cycles of the combination. Ten patients will be enrolled in each cohort (total n = 30) at two collaborating sites. This study was designed to provide preliminary efficacy data across eligible cohorts, with a primary objective of estimating the proportion of pts with an undetectable PSA at 12 months within each cohort. Secondary objectives include safety, proportion of patients with ≥50% decline in PSA from baseline and quality of life measures. Correlative studies will assess blood and tissue molecular biomarkers for association with outcomes. The study is open with two patients enrolled at the time of abstract submission. Clinical trial information: NCT04336943.