Natural course of metastatic castration-resistant prostate cancer in the era of intensified androgen deprivation therapy in the hormone-sensitive setting.

BACKGROUND: Androgen deprivation therapy (ADT) intensification (ADTi) (i.e., ADT with androgen receptor pathway inhibitor or docetaxel, or both) has significantly improved survival outcomes of patients with metastatic hormone-sensitive prostate cancer (mHSPC). However, the impact of prior ADTi in the mHSPC setting on the disease presentation and survival outcomes in metastatic castration-resistant prostate cancer (mCRPC) is not well characterized. In this study, our objective was to compare the disease characteristics and survival outcomes of patients with new mCRPC with respect to receipt of intensified or nonintensified ADT in the mHSPC setting. METHODS: In this institutional review board-approved retrospective study, eligibility criteria were as follows: patients diagnosed with mCRPC, treated with an approved first-line mCRPC therapy, and who received either intensified or nonintensified ADT in the mHSPC setting. Progression-free survival (PFS) was defined from the start of first-line therapy for mCRPC to progression per Prostate Cancer Working Group 2 criteria or death, and overall survival (OS) was defined from the start of first-line therapy for mCRPC to death or censored at the last follow-up. A multivariable analysis using the Cox proportional hazards model was used, adjusting for potential confounders. RESULTS: Patients (n = 387) treated between March 20, 2008, and August 18, 2022, were eligible and included: 283 received nonintensified ADT, whereas 104 were treated with ADTi. At mCRPC diagnosis, patients in the ADTi group were significantly younger, had more visceral metastasis, lower baseline prostate-specific antigen (all p < 0.01), and lower hemoglobin (p = 0.027). Furthermore, they had significantly shorter PFS (median 4.8 vs. 8.4 months, adjusted hazard ratio [HR]: 1.46, 95% confidence interval [95% CI]: 1.07-2, p = 0.017) and OS (median 21.3 vs. 33.1 months, adjusted HR: 1.53, 95% CI: 1.06-2.21, p = 0.022) compared to patients in the nonintensified ADT group. CONCLUSION: Patients treated with ADTi in the mHSPC setting and experiencing disease progression to mCRPC had more aggressive disease features of mCRPC (characterized by a higher number of poor prognostic factors at mCRPC presentation). They also had shorter PFS on first-line mCRPC treatment and shorter OS after the onset of mCRPC compared to those not receiving ADTi in the mHSPC setting. Upon external validation, these findings may impact patient counseling, prognostication, treatment selection, and design of future clinical trials in the mCRPC setting. There remains an unmet need to develop novel life-prolonging therapies with new mechanisms of action to improve mCRPC prognosis in the current era.

Cabozantinib with immune checkpoint inhibitor versus cabozantinib monotherapy in patients with metastatic clear cell renal cell carcinoma progressing after prior immune checkpoint inhibitor.

INTRODUCTION: Rechallenge with antibodies targeting programmed cell death protein-1 or its ligand (PD-1/L1) after discontinuation or disease progression in solid tumors following a prior PD-1/L1 treatment is often practiced in clinic. This study aimed to investigate if adding PD-1/L1 inhibitors to cabozantinib, the most used second-line treatment in real-world patients with metastatic clear cell renal cell carcinoma (mccRCC), offers additional benefits. METHODS: Using de-identified patient-level data from a large real-world US-based database, patients diagnosed with mccRCC, who received any PD-1/L1-based combination in first-line (1L) setting, followed by second-line (2L) therapy with either cabozantinib alone or in combination with PD-1/L1 inhibitors were included. Patients given a cabozantinib-containing regimen in 1L were excluded. The study end points were real-world time to next therapy (rwTTNT) and real-world overall survival (rwOS) by 2L. RESULTS: Of 12,285 patients with metastatic renal cell carcinoma in the data set, 348 patients met eligibility and were included in the analysis. After propensity score matching weighting, cabozantinib with PD-1/L1 inhibitors versus cabozantinib (ref.) had similar rwTTNT and rwOS in the 2L setting. Hazard ratios and 95% confidence interval (CI) for rwTTNT and rwOS are 0.74 (95% CI, 0.49-1.12) and 1.15 (95% CI, 0.73-1.79), respectively. CONCLUSION: In this study, the results align with the phase 3 CONTACT-03 trial results, which showed no additional benefit of adding PD-L1 inhibitor to cabozantinib compared to cabozantinib alone in 2L following PD-1/L1-based therapies in 1L. These results from real-world patients strengthen the evidence regarding the futility of rechallenge with PD-1/L1 inhibitors.

A Phase II Study of Rucaparib Monotherapy in Nonmetastatic, Hormone-Sensitive Prostate Cancer Demonstrating "BRCAness" Genotype (ROAR).

BACKGROUND: Both germline and somatic BReast CAncer gene (BRCA) mutations are poor prognostic markers in men with localized or metastatic prostate cancer. For instance, men with these mutations often are diagnosed with prostate cancer earlier and develop metastatic disease earlier compared with those who do not harbor similar mutations. Patients with germline alterations typically have more advanced disease and shorter overall survival (Castro E, Goh C, Olmos D, et al. Germline BRCA mutations are associated with higher risk of nodal involvement, distant metastasis, and poor survival outcomes in prostate cancer. J Clin Oncol. 2013;31(14):1748-1757. doi:10.1200/JCO.2012.43.1882). The risk of disease progression to metastatic disease is significant in patients with this genotype of prostate cancer. The percentage of patients free from metastatic disease was 90%, 72%, and 50%, respectively, compared with 97%, 94%, and 84% at 3, 5, and 10 years for patients with intact DNA repair (P < .001) (Castro E, Goh C, Leongamornlert D, et al. Effect of BRCA mutations on metastatic relapse and cause-specific survival after radical treatment for localised prostate cancer. Eur Urol. 2015;68(2):186-193. doi: 10.1016/j.eururo.2014.10.022). DNA damage repair non-BRCA mutations include alterations in genes such as ATM, CHEK2, PALB2, and RAD51. While less common than BRCA mutations, they have emerged as significant prognostic markers in prostate cancer. These BRCAness mutations are associated with a higher risk of aggressive disease and poorer survival outcomes. Given the debilitating physical and psychological side effects of androgen deprivation therapy (ADT) in relatively younger men with prostate cancer, delaying ADT in these men may be an attractive strategy. Given the proven efficacy of polyadenosine diphosphate-ribose polymerase (PARP) inhibitors in the castration-resistant prostate cancersetting, PARP inhibitor monotherapy in a nonmetastatic castration-sensitive (nmCSPC) setting has the potential to delay metastasis and delay the onset of ADT related symptoms. METHODS: This is a single-arm, single-center, open-label, phase II trial to assess the efficacy of rucaparib in patients with high-risk biochemically recurrent (BCR) nmHSPC, which was defined as PSA doubling time of <9 months, demonstrating a "BRCAness" genotype (BRCA1/2 and other homologous recombination repair mutations). A total of 15 patients were intended to be enrolled, with an expected enrollment duration of 12 months. Patients were given rucaparib 600 mg orally twice daily and were allowed to remain on study treatment until PSA progression defined by Prostate Cancer Working Group 3, with 2 years of follow-up after study treatment. We anticipated a total of 2-3 years until completion of the clinical trial. The primary endpoint was to assess the PSA progression-free survival (PSA-PFS). The secondary endpoints of the study were safety, the proportion of patients with a PSA 50% response (PSA 50), and an undetectable PSA. A 4-week treatment duration comprised one cycle. RESULTS: The study started enrolling in June 2019 and was prematurely terminated in June 2022 after the accrual of 7 patients because of changing standard of care treatments with the introduction of next-generation scans, eg, prostate-specific membrane antigen positron emission tomography (PSMA-PET). Seven patients were enrolled in the study with the following pathogenic alterations: ATM (n = 3), BRCA2 (n = 2), BRCA1 (n = 1), BRIP1 (n = 1), and RAD51 (n = 1). The median duration of follow-up was 18 months. A median of 20 cycles (range 4-42) was completed, median PSA-PFS was 35.37 months (95% CI, 0-85.11 months). In total, 2 patients achieved PSA50; both also achieved nadir PSA as undetectable. Grade ≥ 3 adverse events (AEs) were anemia and rash (in 1 patient each). No dose-limiting toxicities or severe AEs were seen. CONCLUSION: Rucaparib demonstrated acceptable toxicity and efficacy signal as an ADT-sparing approach in patients with biochemically recurrent nonmetastatic prostate cancer. It is currently challenging to understand the optimal value of systemic therapy in this disease setting due to the rapidly changing standard of care. Additionally, there are relatively few patients with BRCAness who present with nonmetastatic hormone-sensitive prostate cancer (ClinicalTrials.gov Identifier: NCT03533946).

Early PSA Response by 6 Months is Predictive of Treatment Effect in Metastatic Hormone Sensitive Prostate Cancer: An Exploratory Analysis of TITAN Trial.

BACKGROUND: Early PSA response has been found to be prognostic of outcome in metastatic hormone sensitive prostate cancer (mHSPC). We performed a secondary analysis of TITAN trial to determine if early PSA response was predictive of treatment efficacy in mHSPC patients. METHODS: Early PSA response was defined as achieving a PSA level of ≤ 0.2 ng/mL by 6 months of random assignment. A Cox proportional hazard model was constructed in a landmark population with an interaction term between the treatment and early PSA response to determine differential treatment effect on overall survival (OS). We applied multivariable Cox proportional hazard regression model with time to early PSA response fitted with restricted cubic spline to determine the association of time to early PSA response with OS. RESULTS: Approximately 24% (124/524) of patients in the ADT alone group and 61% (321/524) in the apalutamide group had PSA response ≤ 0.2 ng/mL by 6 months. Longer time to early PSA response was associated with significantly superior OS in the apalutamide group. There was a significant difference in treatment effect from apalutamide on OS (p-interaction = 0.03) among 6-month PSA responders (HR: 0.66; 95% CI: 0.44-1.00) versus non-responders (HR: 1.14; 95% CI: 0.89-1.46). This difference in treatment effect was not statistically significant at 3 months (p-interaction = 0.17). Among 6-month PSA responders, 3-year confounder-adjusted OS was 84% (80-88) for the apalutamide group and 74% (66-82) for the ADT alone group. Among non-responders, 3-year adjusted OS for the two treatment arms were 58% (52-65) and 56% (51-60), respectively. CONCLUSIONS: Early PSA response by 6 months was a predictor of treatment efficacy from ADT plus apalutamide on OS. Longer time to early PSA response was associated with superior OS in the apalutamide arm.

Creatine supplementation and resistance training to preserve muscle mass and attenuate cancer progression (CREATINE-52): a protocol for a double-blind randomized controlled trial.

BACKGROUND: Muscle mass is important for metastatic prostate cancer survival and quality of life (QoL). The backbone of treatment for men with metastatic castration sensitive prostate cancer (mCSPC) is androgen deprivation therapy (ADT) with an androgen signaling inhibitor. ADT is an effective cancer treatment, but it facilitates significant declines in muscle mass and adverse health outcomes important to mCSPC survivors, such as fatigue, and reductions in physical function, independence, insulin sensitivity, and QoL. In non-metastatic CSPC survivors, resistance training (RT) preserves muscle mass and improves these related health outcomes, but the biggest barrier to RT in CSPC survivors of all stages is fatigue. Creatine monohydrate supplementation coupled with RT (Cr + RT) may address this barrier since creatine plays a critical role in energy metabolism. Cr + RT in cancer-free older adults and other clinical populations improves muscle mass and related health outcomes. Evidence also suggests that creatine supplementation can complement cancer treatment. Thus, Cr + RT is a strategy that addresses gaps in survivorship needs of people with mCSPC. The purpose of this parallel, double-blind randomized controlled trial is to test the effects of 52-weeks of Cr + RT compared with placebo (PLA) and RT (PLA + RT) on muscle mass, other related health outcomes, and markers of cancer progression. METHODS: We will carry out this trial with our team's established, effective, home-based, telehealth RT program in 200 mCSPC survivors receiving ADT, and evaluate outcomes at baseline, 24-, and 52-weeks. RT will occur twice weekly with elastic resistance bands, and an established creatine supplementation protocol will be used for supplementation delivery. Our approach addresses a major facilitator to RT in mCSPC survivors, a home-based RT program, while utilizing a supervised model for safety. DISCUSSION: Findings will improve delivery of comprehensive survivorship care by providing a multicomponent, patient-centered lifestyle strategy to preserve muscle mass, improve health outcomes, and complement cancer treatment (NCT06112990).

Treatment patterns and outcomes in patients with nonmetastatic castration-resistant prostate cancer in the United States.

Aim: Androgen receptor pathway inhibitors (ARPIs) prolong metastasis-free survival and overall survival in patients with nonmetastatic castration-resistant prostate cancer (nmCRPC). This study aimed to evaluate real-world treatment patterns, utilization and survival outcomes in patients with nmCRPC. Patients & methods: This retrospective cohort study used Optum database electronic health records of patients with nmCRPC from 1 January 2007 to 31 December 2020 in the US. Results: Of 1955 patients, >80% received androgen-deprivation therapy (ADT) alone or ADT + first-generation nonsteroidal antiandrogen (NSAA) as first-line treatment, while only 8.24% received ADT + ARPI. ADT + ARPI remained underutilized even among those with high-risk nmCRPC. Further, ADT + NSAA had no survival benefit compared with ADT alone. Conclusion: Practice-improvement strategies are needed for treatment intensification with ARPIs for patients with nmCRPC.

Prostate cancer cells often use hormones called androgens to grow and survive. Hormone therapy is a treatment that lowers the amount of these hormones in the body to slow down the cancer's growth. It includes androgen-deprivation therapy (ADT), which can either be used alone or along with nonsteroidal antiandrogens (NSAAs) or with androgen receptor pathway inhibitors (ARPIs). Nonmetastatic castration-resistant prostate cancer (nmCRPC) is defined as prostate cancer that has not spread to other parts of the body but exhibits rising levels of serum prostate-specific antigen despite surgery or ADT to reduce androgens. Research shows that ARPIs can improve survival in patients with nmCRPC, but more data on its use are needed. This study looked at the electronic health records of patients with nmCRPC to review the treatment they had received and their survival. Between 2008 and 2020, most patients received ADT alone or with NSAA. Even though the number of patients receiving ADT with ARPI increased during this period, it remained underused, even in patients with a high risk of cancer spreading to other body parts. Post-2018, even after 2 years of these drugs being available, only about one in five patients received ADT with ARPI. Also, people who received ADT with NSAA did not have a longer survival than patients treated with ADT alone. The study indicates that ARPIs, which could improve survival of patients with nmCRPC, are not being utilized optimally. Strategies that promote early use of ARPIs are needed to improve survival of patients with nmCRPC.

Impact of androgen receptor alterations on cell-free DNA genomic profiling on survival outcomes in metastatic castration-resistant prostate cancer.

BACKGROUND: Androgen receptor (AR) gene alterations, as detected by circulating tumor cell-free DNA (cfDNA) genomic profiling, have been shown to emerge after a variable duration of androgen signaling inhibition. AR alterations were associated with inferior outcomes on treatment with androgen receptor pathway inhibitors (ARPI) in the first line metastatic castration-resistant prostate cancer (mCRPC) setting in a phase 2 trial. Here in, we assessed the impact of these AR alterations on survival outcomes in a real-world patient population of mCRPC experiencing disease progression on an ARPI. METHODS: In this IRB-approved retrospective study, consecutively seen patients with a confirmed diagnosis of mCRPC, with disease progression on a treatment with ARPIs in the first line mCRPC setting, with no prior exposure to an ARPI in the castration sensitive setting, and with available cfDNA profiling from a CLIA certified laboratory were included. Patients were categorized based on AR status: wild-type (ARwt ) or alteration-positive (AR+ ). The objective was to correlate overall survival (OS) after disease progression on the first-line ARPI with the presence or absence of AR alterations. Kaplan-Meier and Cox Regression Tests were used as implemented in R-Studio (v.4.2). RESULTS: A total of 137 mCRPC patients were eligible: 69 with ARwt versus 68 with AR+ . The median OS posttreatment with the first ARPI was significantly higher for ARwt than AR+ patients (30.1 vs. 15.2 mos; p < 0.001). Of 108 patients who received a subsequent line of therapy, 63 received an alternate ARPI (AR+ 39 vs. 24 ARwt ), while 20 received a taxane-based therapy (11 AR+ vs. 9 ARwt ). Among patients receiving an alternate ARPI, AR+ had numerically shorter OS (16.8 vs. 30.4 mos, p = 0.1). Among patients receiving taxane-based regimens, the OS was not significantly different between AR+ and ARwt (14.5 vs. 10.1 mos, p = 0.18). CONCLUSION: In this real-world study, mCRPC patients with AR alterations on cfDNA had inferior OS after disease progression on the first ARPI, compared to those who did not, and may impact outcomes on a subsequent ARPI but not on subsequent taxane-based therapy received. By providing survival estimates for patients with or without AR alterations, our data may aid in patient counseling, prognostication, treatment decision, and for designing future clinical trials in this setting.

Phase I Trial of Combination Therapy With Avelumab and Cabozantinib in Patients With Newly Diagnosed Metastatic Clear Cell Renal Cell Carcinoma.

BACKGROUND: Combination immunotherapy is now considered the standard first-line therapy for patients with metastatic clear cell renal cell carcinoma (mccRCC) after multiple clinical trials demonstrated improved overall survival compared with single-agent tyrosine kinase inhibitors. Cabozantinib modulates critical components of the immune system, such as decreasing regulatory T cells and increasing T-effector cell populations, and is approved for the treatment of mRCC. Avelumab is a human IgG1 monoclonal antibody that binds to programmed death-ligand 1 protein and inhibits the interaction with PD-1. This phase I trial assessed the safety and clinical activity of avelumab and cabozantinib combination therapy in mccRCC. METHODS: This study was a phase I, 3+3 dose escalation clinical trial. The primary endpoint was the safety and identification of the recommended phase II dose (RP2D). Secondary endpoints included objective response rate (ORR) and radiographic progression-free survival (rPFS). There were 3 dose cohorts: cabozantinib 20, 40, and 60 mg/day, each combined with avelumab (10 mg/kg intravenously every 2 weeks). An additional 3 patients were included in the final dose cohort as a confirmation of the RP2D. No dose modifications were allowed for avelumab, but dose delays were permitted. Both dose reductions and holds were allowed for cabozantinib. Response Evaluation Criteria in Solid Tumors (RECIST), version 1.1, was used to determine ORR, and treatment beyond progression was allowed. RESULTS: Twelve patients with newly diagnosed mccRCC were enrolled from July 2018 until March 2020. Three patients were enrolled in the 20 and 40 mg cohorts each, and 6 were enrolled in the 60 mg cohort. The International Metastatic RCC Database Consortium (IMDC) risk categories for these patients were: 4 patients (favorable risk), 6 patients (intermediate risk), and 2 patients (poor risk). No dose-limiting toxicities (DLTs) were observed in any cohort. Six patients developed serious adverse events related to study treatment after the DLT window period. Immune-related adverse events (iRAEs) were reported in 11 patients; fatigue and diarrhea were the most common (each with n = 4, 33.3%), followed by maculopapular rash and hand-foot syndrome (each with n = 3, 25%). Dose reductions were required in 5 of 6 patients in the cabozantinib 60 mg cohort after the DLT period. One patient discontinued avelumab due to irAE (nephritis), while none discontinued cabozantinib due to toxicity. The ORR was 50%, with one complete response (CR) and 5 partial responses (PR). The disease control rate (CR + PR + stable disease) was noted in 92% of the patients. Radiological PFS survival rate at 6 and 12 months was reported in 67.7% and 33.5% of patients, respectively. CONCLUSION: Combination therapy with avelumab and cabozantinib is safe and showed preliminary clinical activity in mccRCC. Even though the DLT was not met in any of the 3 cohorts, the recommended RP2D dose for the combination is cabozantinib 40 mg/day due to a high incidence of grade 2 toxicity for cabozantinib 60 mg/day after the DLT period. (ClinicalTrials.gov Identifier: NCT03200587).

The Role of Physician Specialty in the Underutilization of Standard-of-Care Treatment Intensification in Patients With Metastatic Castration-sensitive Prostate Cancer.

PURPOSE: We evaluate utilization of treatment intensification of androgen deprivation therapy with androgen receptor pathway inhibitor/docetaxel for metastatic castration-sensitive prostate cancer patients across physician specialties. MATERIALS AND METHODS: This retrospective study identified patients with metastatic castration-sensitive prostate cancer in the Optum Research Database between 2014 and 2019. Adult men with ≥1 claim for metastatic disease within 90 days before or any time after the first prostate cancer claim who received androgen deprivation therapy were included. Physician specialty, determined from medical/pharmacy claims during each line of therapy, was categorized as urologist only, oncologist only, both (urologists and oncologists), or other (other specialties). Treatment intensification and patient characteristics were analyzed descriptively. RESULTS: Of 4,675 patients, 16% were treated by urologists only, 20% by oncologists only, 63% by both, and 1.1% by others. The most frequent first line of therapy was androgen deprivation therapy ± first-generation nonsteroidal antiandrogens (>50%). Androgen deprivation therapy + docetaxel use declined over time, while androgen deprivation therapy + androgen receptor pathway inhibitor use increased. Patients seen by oncologists or both were younger, had fewer comorbidities, and were likelier to receive treatment intensification compared to those treated by urologists. By 2019, however, treatment intensification remained <40% from oncologists only or both, and <15% from urologists only. In the second and third lines of therapy, androgen deprivation therapy + androgen receptor pathway inhibitor was the most prescribed regimen across specialties (>50%). CONCLUSIONS: Treatment intensification was underused in first lines of therapy across urology and oncology specialties despite evidence of improved survival. In subsequent lines, androgen deprivation therapy + androgen receptor pathway inhibitor was prescribed more frequently across specialties. These results underscore the need for earlier treatment intensification by urologists and oncologists.

Multi-institutional Analysis of the Clinical and Genomic Characteristics of Black Patients with Metastatic Hormone-Sensitive Prostate Cancer.

BACKGROUND: The outcomes of metastatic hormone-sensitive prostate cancer (mHSPC) have significantly improved through treatment intensification, yet Black representation in those studies is suboptimal. METHODS: A multi-institutional, retrospective analysis of Black men with mHSPC was conducted, focusing on baseline demographics, treatment patterns, genomic profiles, clinical outcomes including prostate-specific antigen response, time to castrate-resistant prostate cancer (CRPC), and subsequent treatments. RESULTS: A total of 107 patients, median age 64 years, 62% with de novo metastases at diagnosis and 64% with high-volume disease, were included. Twenty-nine patients (27%) were treated with androgen deprivation therapy (ADT) with and without first generation anti-androgens, while 20%, 38% and 5% received chemotherapy, abiraterone, and enzalutamide, respectively. At time of data cut-off, 57 (54%) patients had developed CRPC, with a median time to CRPC of 25.4 months (95% CI 20.3-30.4). The median time to CRPC was 46.3 months (18.9-73.7) and 23.4 months (18.6-28.2) for patients who received ADT with or without first-generation anti-androgens and treatment intensification, respectively. The 2-year survival rate was 93.3%, and estimated median overall survival of was 74.9 months (95% CI, 68.7-81.0). Most patients (90%) underwent germline testing; the most frequent known alterations were found within the DNA repair group of genes. Somatic testing revealed pathogenic alterations of interest, notably TP53 (24%) and CDK12 (12%). CONCLUSION: In our cohort, Black men with mHSPC presented with a high proportion of de novo metastases and high-volume disease. Treatment outcomes were very favorable with ADT-based regimens. The genomic landscape suggests different molecular profile relative to White patients with potential therapeutic implications.

Comprehensive Genomic Profiling of Cell-Free DNA in Men With Advanced Prostate Cancer: Differences in Genomic Landscape Based on Race.

Advanced prostate cancer (aPC) in Black men was reported to present with aggressive features and to be associated with poor prognosis. Herein, we compared the cell-free DNA (cfDNA) genomic landscape of aPC in Black vs White men. Patients (pts) with aPC from 6 academic institutions and available cfDNA comprehensive genomic profiling (CGP) were included. Association between mutated genes and race was evaluated using Barnard's test and a Probabilistic Graphical Model (PGM) machine learning approach. Analysis included 743 aPC pts (217 Black, 526 White) with available cfDNA CGP. The frequency of alterations in the androgen receptor gene was significantly higher in Black vs White men (55.3% vs 35% respectively, P < .001). Additionally, alterations in EGFR, MYC, FGFR1, and CTNNB1 were present at higher frequencies in Black men. PGM analysis and Barnard's test were concordant. Findings from the largest cohort of Black men with aPC undergoing cfDNA CGP may guide further drug development in these men.

Radium-223 plus Enzalutamide Versus Enzalutamide in Metastatic Castration-Refractory Prostate Cancer: Final Safety and Efficacy Results.

LESSONS LEARNED: Long-term safety of radium-223 with enzalutamide was confirmed in this clinical trial. PSA-PFS2 was prolonged with the combination compared with enzalutamide alone. BACKGROUND: Previously, we showed the combination of radium-223 and enzalutamide to be safe and associated with improved efficacy based on a concomitant decline in serum bone metabolism markers compared with enzalutamide alone in a phase II trial of men with metastatic castration-resistant prostate cancer (mCRPC) [1]. METHODS: Secondary endpoints were not included in our initial report, and we include them herein, after a median follow-up of 22 months. These objectives included long-term safety, prostate-specific antigen (PSA)-progression-free survival (PFS), and radiographic progression-free survival; PSA-PFS2 (time from start of protocol therapy to PSA progression on subsequent therapy); time to next therapy (TTNT); and overall survival (OS). Survival analysis and log-rank tests were performed using the R statistical package v.4.0.2 (https://www.r-project.org). Statistical significance was defined as p < .05. RESULTS: Of 47 patients (median age, 68 years), 35 received the combination and 12 enzalutamide alone. After a median follow-up of 22 months, final safety results did not show any increase in fractures or other adverse events in the combination arm. PSA-PFS2 was significantly improved, and other efficacy parameters were numerically improved in the combination over the enzalutamide arm. CONCLUSION: The combination of enzalutamide and radium-223 was found to be safe and associated with promising efficacy in men with mCRPC. These hypothesis-generating results portend well for the ongoing phase III PEACE III trial in this setting.

Identification of Somatic Gene Signatures in Circulating Cell-Free DNA Associated with Disease Progression in Metastatic Prostate Cancer by a Novel Machine Learning Platform.

PURPOSE: Progression from metastatic castration-sensitive prostate cancer (mCSPC) to a castration-resistant (mCRPC) state heralds the lethal phenotype of prostate cancer. Identifying genomic alterations associated with mCRPC may help find new targets for drug development. In the majority of patients, obtaining a tumor biopsy is challenging because of the predominance of bone-only metastasis. In this study, we hypothesize that machine learning (ML) algorithms can identify clinically relevant patterns of genomic alterations (GAs) that distinguish mCRPC from mCSPC, as assessed by next-generation sequencing (NGS) of circulating cell-free DNA (cfDNA). EXPERIMENTAL DESIGN: Retrospective clinical data from men with metastatic prostate cancer were collected. Men with NGS of cfDNA performed at a Clinical Laboratory Improvement Amendments (CLIA)-certified laboratory at time of diagnosis of mCSPC or mCRPC were included. A combination of supervised and unsupervised ML algorithms was used to obtain biologically interpretable, potentially actionable insights into genomic signatures that distinguish mCRPC from mCSPC. RESULTS: GAs that distinguish patients with mCRPC (n = 187) from patients with mCSPC (n = 154) (positive predictive value = 94%, specificity = 91%) were identified using supervised ML algorithms. These GAs, primarily amplifications, corresponded to androgen receptor, Mitogen-activated protein kinase (MAPK) signaling, Phosphoinositide 3-kinase (PI3K) signaling, G1/S cell cycle, and receptor tyrosine kinases. We also identified recurrent patterns of gene- and pathway-level alterations associated with mCRPC by using Bayesian networks, an unsupervised machine learning algorithm. CONCLUSION: These results provide clinical evidence that progression from mCSPC to mCRPC is associated with stereotyped concomitant gain-of-function aberrations in these pathways. Furthermore, detection of these aberrations in cfDNA may overcome the challenges associated with obtaining tumor bone biopsies and allow contemporary investigation of combinatorial therapies that target these aberrations. IMPLICATIONS FOR PRACTICE: The progression from castration-sensitive to castration-resistant prostate cancer is characterized by worse prognosis and there is a pressing need for targeted drugs to prevent or delay this transition. This study used machine learning algorithms to examine the cell-free DNA of patients to identify alterations to specific pathways and genes associated with progression. Detection of these alterations in cell-free DNA may overcome the challenges associated with obtaining tumor bone biopsies and allow contemporary investigation of combinatorial therapies that target these aberrations.

Comparative Effectiveness of Immune Checkpoint Inhibitors in Patients with Platinum Refractory Advanced Urothelial Carcinoma.

PURPOSE: Five programmed cell death protein 1 or its ligand (L1) inhibitors are approved for treatment of platinum refractory, locally advanced/unresectable or metastatic urothelial carcinoma. However, their comparative effectiveness is unknown. We compared time to initiation of third therapy or death, and overall survival with different programmed cell death protein 1/L1 inhibitors in patients with platinum refractory metastatic urothelial carcinoma. MATERIALS AND METHODS: Patient-level data were extracted from a real-world de-identified database. Comparative effectiveness was inferred via Cox proportional hazards model, weighted by matching weights. Each patient's propensity for each treatment was modeled via random forest, based on potential drivers of treatment selection. A propensity score for each therapy was used to calculate a matching weight, targeting the same estimand as 1:1 matching of treatment groups with balance among potential confounders. Eligibility criteria included diagnosis of metastatic urothelial carcinoma, receipt of first line treatment with a platinum based chemotherapy, followed by initiation of single agent programmed cell death protein 1/L1 inhibitor after disease progression from August 1, 2016 through May 1, 2019. RESULTS: Overall, 609 patients were eligible for analysis. Median time to initiation of third therapy or death with atezolizumab, nivolumab and pembrolizumab was 4.2, 5.3 and 4.5 months, respectively, and median overall survival was 6.4, 8.0 and 8.3 months, respectively. Matching weighted analyses did not show strong evidence of differences among programmed cell death protein 1/L1 inhibitors in terms of time to initiation of third therapy or death and overall survival. CONCLUSIONS: In this large real-world cohort, effectiveness in terms of time to initiation of third therapy or death and overall survival with programmed cell death protein 1/L1 inhibitors in patients with platinum refractory locally advanced/unresectable or metastatic urothelial carcinoma was similar.

Landmark Series on Disparities in Surgical Oncology: Melanoma.

BACKGROUND: Although the lifetime risk of melanoma is disproportionately higher in whites, blacks have a poorer overall survival with an absolute survival difference of 25%. Significant progress has been made in melanoma treatment in the past decade; however, these successes may not be available or accessible to all segments of the population. METHODS: In this review, we highlight important studies in melanoma as well as informative retrospective studies from databases and nonmelanoma cancers where appropriate. RESULTS: There are no level I evidence-based studies on disparities in melanoma, and most likely there will never be, but the studies presented herein and clinical experience demonstrate that disparities in clinical outcomes from melanoma exists. CONCLUSIONS: By becoming aware of the disparities, we can help mitigate them by engagement, education, and corrective and empowering actions through awareness campaigns, appropriate clinical trial design, encouraging participation in clinical trials, increasing the diversity of providers, and advocacy.

The Quest for an Ideal Neoadjuvant Systemic Therapy in Cisplatin-Ineligible Patients with Muscle-Invasive Localized Urothelial Carcinoma.

This commentary reviews current progress in neoadjuvant immunotherapy for muscle­invasive localized urothelial carcinoma, highlighting opportunities and challenges with recent neoadjuvant immunotherapy trials.

Ipilimumab-induced hypophysitis, a single academic center experience.

BACKGROUND: Immune checkpoint inhibitors, single or in combination, have recently become a cornerstone for the treatment of many malignancies. Ipilimumab, a CTLA-4 inhibitor, was initially FDA approved for treatment of unresectable or metastatic melanoma and subsequently in combination therapy for other cancers. Ipilimumab-induced hypophysitis (IH) risk of development varies in different studies between 0 and 17%. Furthermore, little is known on how to predict which patients will develop IH and its impact on efficacy of Ipilimumab and survival for these patients. Here we reviewed IH and its impact on progression-free survival (PFS) and overall survival (OS). METHODS: Retrospective, IRB- approved review of consecutive 117 melanoma patients who received ipilimumab between 2011 and 2016 was undertaken. Demographic and clinical characteristics, treatment timing and doses, time to progression after therapy, and survival data were reviewed. Patients were predefined in two groups: patients with and without IH. Descriptive statistics were used to summarize the demographic and clinical characteristics of the study sample. All values are shown as means and standard deviation [mean (SD)] unless indicated otherwise. P < 0.05 was considered to be statistically significant. RESULTS: Of the 117 patients, 15 (12.8%) with a median age of 62.1 years developed IH. In the IH cohort, 10 (66.7%) were male and were significantly older than females (median 67.7 vs. 50.8; P = 0.009). This difference was not seen in non-IH group. Male patients with IH were significantly older than males without IH (67.7 vs. 56.4 years, P = 0.020), however this difference was not observed in females. No patient who received prior cancer systemic therapy (0/30) developed IH vs. 17.2% (15/72) without prior therapy developed IH (OR 0.00; 95% CI 0.00 to 0.73, P = 0.011). Between IH and non-IH patients, there was no difference in gender, race, ethnicity, BMI, diabetes or autoimmune disease at baseline, number of administered ipilimumab cycles, presence of primary melanoma lesion, or BRAF status. IH and non-IH patients had a similar median PFS (8.1 vs. 6.8 months, HR = 0.51, 95% CI 0.24 to 1.05 P = 0.062) and OS (53.3 vs. 29.5 months; HR 0.66, 95% CI 0.30 to 1.46; P = 0.307). CONCLUSION: In this study of melanoma patients treated with Ipilimumab, risk of developing IH was high (almost 13%). Older age in men and no prior cancer therapy were associated with IH higher risk. Development of IH was not associated with PFS or OS. Increased use of immune checkpoint inhibitors in the future will impact IH overall risk, thus awareness is needed. Given the lack of reliable identifiable risk factors, close monitoring of signs and symptoms after each therapy cycle is critical for early detection and treatment of hypophysitis.